cosmetiscope-03-2014-web

MARCH 2014 • Vol. 20 No. 3

Table of Contents Symposium Registration Information and Agenda Page 4-5 Directions to the NYSCC Rheology Symposium Page 6-7 NYSCC Rheology Symposium Hotel Information Page 7 NYSCC Rheology Symposium Committee & Companies Participating in the NYSCC Rheology Symposium Poster Session and Instrument Demonstrations Page 8 Grow with the Flow: The Importance of Rheology in Product Development – Hemi Naé Page 9-12 The Hitchhiker’s Guide to Rheology – Timothy Gillece Page 12-15 Formulating with Rheology Modifiers – Joseph Albanese Page 15-18 Rheology, Theology, Salvador Dali and God – Joseph Albanese Page 18-22 Mona Lissajous: Where Science Brushes Art – Timothy Gillece Page 22-25 Antioxidant Symposium Information and Agenda Page 26-27 2014 Tri-Princeton Events Page 28 Plant Science Seminar Page 28 Employment Opportunities Page 29-32

2014 NYSCC Rheology Symposium

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o NOT miss this wonderful opportunity to learn more about the intriguing science of rheology and its importance to achieving commercial success. We hope to see you on March 19th and 20th at the beautiful campus of Princeton University. If you plan to attend, please take a few moments to familiarize yourself with the campus map and directions to the McDonnell Building and Prospect House. For the daytime programs and the evening program on March 19th please use the visitors section of Parking Lot 21. If walking, follow the signs to McDonnell. It is a short walk from the parking lot. There will also be shuttle bus service provided. Also, up until March 12th, students, emeritus and unemployed members may attend at no charge. But be forewarned, after March 12th we must charge a nominal fee.

Everyone who attends will receive copies of all of the speaker presentations. Attendees will also receive a print version of the March issue of Cosmetiscope, which is a compilation of past articles covering the subject of rheology. Treasure it. It will be the last print edition of our Chapter’s newsletter for you to keep in your library; and it will be available only in a limited number of copies as we have already progressed to fully digital versions. We will also raffle off 10 copies of Rheology Essentials of Cosmetic and Food Emulsions

by Dr. Rüdiger Brummer.

Those attending the first day of the Symposium may elect to attend one or both of the SCC Continuing Education Courses. These courses, run by the National Organization, are already a terrific bargain, but the NYSCC has made them even more affordable than before. These two courses are a wonderful introduction to the science of rheology.

March 19th-20th • Princeton University, Princeton, NJ

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2014 NYSCC BOARD OF DIRECTORS & PROGRAM CHAIRS CHAIR

Steve Neidenberg sbn605@aol.com

CHAIR-ELECT

Kim Burch (609) 443-2385 Kim.Burch@elementis.com

TREASURER

Sonia Dawson sonia.dawson@croda.com

TREASURER-ELECT

Marie Thadal (609) 712-3716 nyscctreasurerelect@gmail.com

SECRETARY

Jenna Jelinski (201) 396-8431 jjelinski@morretec.com

ADVISOR

Steve Herman (973) 479-5702 steveh50@optonline.net

HOUSE

Andrea Guerrero aguerrero@gattefossecorp.com (862) 324-1063

MEMBERSHIP

Amy Marshall (908) 806-4664 amy.marshall@altana.com

PROGRAM

Cathy Piterski (678) 730-1643 cpiterski@essentialingredients.com

SPECIAL EVENTS John Dinoia (845) 664-4862 jdinoia@espllc.us

SUPPLIERS’ DAY

Sandy Chapin schapin@allured.com

COSMETISCOPE EDITOR Roger McMullen roger_mcmullen@fdu.edu

COSMETISCOPE ADVERTISING Bret Clark rbclark@ashland.com

COSMETISCOPE EMPLOYMENT Jason O’Neill (631) 252-2939 Jason.Oneill@kemin.com

Annual European Rheology Conference April 8-11, 2014 • Karlsruhe, Germany For more information visit www.aerc2014.kit.edu. E-mail: info@aerc2014.kit.edu.

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Cosmetics in Contemporary Brazil May 12, 2014 Renaissance Woodbridge • Iselin, NJ The New York Chapter of the Society of Cosmetic Chemists

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member of the rising economic powers, otherwise known as the BRIC nations and a significant emerging market, Brazil is Latin America's largest economy and the fifth largest country in the world with a population estimated to be about 200 million. Demographically, Brazil is one of the most ethnically diverse countries and a major consumer of personal care products and fragrances. Brazil’s biological diversity is the largest in the world. It is blessed with abundant raw materials, which have many uses in personal care. As more companies are embracing globalization to reach new customers in new markets, a greater understanding of consumer preferences, important product types, and regulatory issues in this vast and growing market is essential. The NYSCC, in conjunction with its world renowned Suppliers’ Day event, has assembled a program of experts to further explore this land of immense opportunities.

n AGENDA

8:00 − 8:30 a.m.

8:30 − 8:45 a.m.

8:45 − 9:30 a.m.

9:30 − 10:15 a.m.

10:15 − 10:30 a.m.

10:30 − 11:15 a.m.

11:15 − 12:00 p.m.

12:00 − 1:00 p.m.

1:00 − 1:45 p.m.

1:45 − 2:30 p.m.

2:30 − 2:45 p.m.

2:45 − 3:30 p.m.

3:30 − 4:15 p.m.

4:15 − 5:00 p.m.

5:00 − 5:15 p.m.

REGISTRATION OPENING COMMENTS Dawn Thiel Glaser Brazil (Beraca) − A Land of Opportunities: Vast Natural Resources and A Growing Personal Care Market Alberto Keidi Kurebayashi (Protocolo Consultoria Personal and Health Care) − Guidelines to Develop Functional and Acceptable Hair and Skin Care Products for the Brazilian Market BREAK Mohamed Omer (Mintel) − By the Numbers: The Personal Care Market in Brazil Jean-François Molina (Solabia) − Overview of Brazilian Biodiversity and its Contribution to Skin and Hair Beauty LUNCH Sergio Oliveir (J&J) − Regulatory and Safety Issues in Brazil Silvia Staniscuaski Guterres (Universidade Federal do Rio Grande do Sul) − Innovative Nanotechnology-based Cosmetics in Brazil: State-of-the-Art and Trends BREAK Dr. Rakesh Jain (Amyris) − Cosmetic Products from Sugarcane Emiro Khury (EK Consultores) − Technological Advances and Regulatory Aspects in Sunscreens Products in Latin America Ana Palombo (Coty) − The Brazilian Fragrance Market CLOSING REMARKS

n COST & REGISTRATION SCC Members $75.00 • Non-members $95.00 • Emeritus Members Free if pre-registered • Students with valid ID $10.00 At the door: $30.00 surcharge in all categories.

Register online at www.nyscc.org. • Registration questions: John Carola at johnc@protameen.com.

n COST & REGISTRATION Renaissance Woodbridge Hotel 515 US Highway 1, South, Iselin, NJ 08830 • GPS Address: 401 Gill Lane, Iselin, NJ 08830 Hotel is at the corner US HWY 1 South and Gill Lane.

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2014 NYSCC 2-Day Rheology Symposium Princeton University (McDonnell & Jadwin Buildings)

March 19-20, 2014

n Half-day SCC Cosmetic Rheology Course by Dennis Laba n

Half-day SCC Gums, Thickeners and Rheology Modifiers Course

by Robert Lochhead, Ph.D.

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Presentations By Internationally Renowned Experts in Rheology including Poster Technology Session

n Rheology Instrumentation Demonstrations

Agenda:

n SESSION A – March 19th, 8:35 – 11:30 a.m.

SCC Continuing Education Course: “Cosmetic Rheology.”

Instructor: Dennis Laba (Presperse) n SESSION B – March 19th, 9:00 – 11:30 a.m.

• Joe Albanese (3V Inc) – Rheology Modifiers as Delivery Systems for Active Ingredients • Rhyta Rounds, Ph.D. (Fluid Dynamics) – Lubricity Measurements—An Overview • Daphne Benderly, Ph.D. (Presperse) – Why Rheology—Examples from Other Industries • Jeffery Martin, Ph.D. (Johnson & Johnson) – Yield Stress Measurements for Personal Care Applications • Christina Tang, Ph.D. (Princeton University) – Foams for Drug Delivery • Geng Li, Ph.D. (Energizer) – Relationship Between the Rheological Properties and Skin Feel

n SESSION C – March 19th, 1:00 – 4:00 p.m.

SCC Continuing Education Course: “Rheology Modifiers.”

Instructor: Robert Lochhead, Ph.D. (University of Southern Mississippi)

n SESSION D – March 19th, 1:00 – 4:00 p.m.

• Gail Vance Civille (Sensory Spectrum) – Rheology—Can You Feel It…When Sensory Science Counts • Nava Dayan, Ph.D. (Dr. Nava Dayan L.L.C.) – Formulation Viscosity—Correlation to Skin Permeation Enhancement or Retardation • Anna Tai, Ph.D. (Merck) – Rheology Application for Emulsion Formulation Development, Optimization & Scale-up • Kishore R. Shah, Ph.D. (Polytherapeutics, Inc.) – Hydrogel Graft Copolymer Delivery System and I ts Rheological Properties • Brian Figura (Lubrizol Advanced Materials, Inc.) – Surfactant-Activated Microgels: A Novel Platform for Rheology Modification • Mark Chandler (ACT Solutions Corp) – Cosmetic Rheology—A Flow of Emotions • Bharath Rajaram (TA Instruments) – Rheological Characterization of Personal Care Products • Brock Lundberg (Fiberstar Bio-Ingredient Technologies, Inc.) – Characterization of Citrus Fiber Rheology and Physicochemical Interactions • Eric Chiang (Brookfield Engineering) – Are Your Cosmetics & Personal Care Products Easy to Apply • Edward DiAntonio (Ashland) – The Impact of Hydrophobically Modified HEC on the Rheology of Conditioner Formulations

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n SESSION E – March 20th, 9:00 a.m. – 12:15 p.m.

Keynote Speaker Robert Bianchini, Ph.D. (VP Innovation Merck) The Importance of Rheology to a Successful Product Development Plan • Hemi Naé, Ph.D. (Hydan Technologies) – Introduction to Rheology • Rudiger Brummer, Ph.D. (formerly with Beiersdorf) – Correlating RheologicalProperties To Sensory Perceptions • T.J. Lin, Ph.D. (TJL Associates) – Rheology and Solving Emulsion Processing Problems

n SESSION F – March 20th, 1:30 – 4:30 p.m.

• Manfred Wilhelm, Ph.D. (Karlsruhe Institute of Technology) – New and Combined Methods for the Rheological Characterization of Soft Matter • Robert Prud’homme, Ph.D. (Princeton University) – Hydrophobically Associative Polymers • Robert Lochhead, Ph.D. (University of Southern Mississippi) – Microgels and Particulates: Yield Stress, Jamming and Avalanche Fluids • Phillip Miner, Ph.D. (formerly with Unilever)– Using Rheology to Predict Stability

ALL DAY – March 19th and 20th Demonstrations/Presentations of Rheological Instrumentation Poster Technology Session – Rheology Modifiers

BOTH EVENINGS – March 19th and 20th March 19th – Evening Educational Program: Gary Agisim (Pfizer) – TBD Social Gala Reception (Chemistry building, Princeton University campus) March 20th – Evening Educational Program: Dr. Trefor Evans (T A Evans LLC) – Use of the Viscoelastic Properties of Hair in the Elucidation of its Complex Structure Reception (Prospect House, Princeton University campus) Reception (food and drink) on both evenings starts at 5:00 p.m. until about 8:00 p.m.

Registration:

Members

NonMembers

Students/Emeritus/ Unemployed

Both Days One Day

$200 $100

$400 $200

$0 $0

Price includes reception(s) at the conclusion of the presentations.

Both Days One Day

$300 $150

$500 $250

$50 $25

Price includes reception(s) at the conclusion of the presentations.

Day 1 Day 2 Both Days

$25 $25 $50

$50 $50 $100

Free Free Free

n EARLY REGISTRATION – PRIOR TO MARCH 12, 2014

n LATE REGISTRATION – AFTER MARCH 12, 2014 AT THE DOOR n RECEPTION ONLY – Early registration required.

n POSTER TECHNOLOGY SESSION PARTICIPATION

•$600 includes 4'x8' poster, one full-registration, published abstract, and 1/4-page advertisement in handouts.

• $800 includes 4'x8' poster, one full-registration, published abstract, and full-page advertisement in handouts plus sponsorship of both early evening receptions NOTE: Poster participation includes one full-registration!

n CONTACTS:

• Joe Albanese (3V Inc) at j.albanese@3vusa.com or (908) 456-2968 • Daphne Benderly (Presperse) at dbenderly@presperse.com or (732) 356-5200

For directions and parking information go to the NYSCC website: www.nyscc.org.

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Directions to the NYSCC Rheology Symposium McDonnell Hall • Princeton University Washington Road, Princeton, New Jersey

n GPS Directions: f you are using a vehicle navigation device to assist you with directions to campus, use the address 200 Elm Drive, Princeton, New Jersey, which will direct you to the guard booth at the south end of campus and to the Department of Public Safety. See directions to parking Lot 21 for further details.

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n From the NORTH/NEW YORK CITY Take the New Jersey Turnpike south to Exit 9 (New Brunswick). After the tollbooths, take the first right turn onto the ramp for Route 18 North. Soon after you enter Route 18, take the left side of a fork in the road, staying in the right lane. Immediately bear right for an exit to U.S. Route 1 South/Trenton.

Drive south on Route 1 for about 16 miles to the Washington Road Exit, which is a traffic circle. Take the first right off the circle (between the gas stations) toward Princeton. The campus is located approximately a mile straight ahead. See directions to parking Lot 21 for further details.

n From the WEST Drive east on Interstate 78 into New Jersey. Exit onto southbound Interstate 287 (toward Somerville).

Follow signs for Routes 202/206 south. Drive south on 202 for a short distance and then follow signs to 206 south, which will take you around a traffic circle. Go south on 206 for about 18 miles to Nassau Street (Route 27) in the center of Princeton. Turn left onto Nassau Street, and follow it to the third traffic light. Turn right onto Washington Road. See directions to parking Lot 21 for further details. n From the SOUTH If you are coming from southern New Jersey, we recommend that you take Interstate 295 North (instead of the New Jersey Turnpike). Take Exit 67 to Route 1 North. Travel about three miles north on Route 1 to the Washington Road Exit, which is a traffic circle. Go three quarters of the way around the circle and turn right (between the gas stations) toward Princeton. The campus is located approximately a mile straight ahead.

See directions to parking Lot 21 for further details.

n From the EAST Take Interstate 195 West (toward Trenton) to the exit for Interstate 295 North. Drive seven miles to the exit for Route 1 North (Exit 67). Travel about three miles north on Route 1 to the Washington Road Exit, which is a traffic circle. Go three quarters of the way around the circle and turn right (between the gas stations) toward Princeton. The campus is located approximately a mile straight ahead. See directions to parking Lot 21 for further details.

n From the PHILADELPHIA AREA Take Interstate 95 North into New Jersey and exit at Route 1 North (Exit 67). Travel about three miles north on Route 1 to the Washington Road Exit, which is a traffic circle. Go three quarters of the way around the circle and turn right (between the gas stations) toward Princeton. The campus is located approximately a mile straight ahead. See directions to parking Lot 21 for further details. n Directions to Lot 21: Heading north on Washington Road (away from Route 1), turn right onto Faculty Road. (If you are heading south on Washington Road from Nassau Street/Route 27, turn left onto Faculty Road instead.)

After passing Jadwin Gym, turn left on FitzRandolph Road and then take the first left turn into Lot 21.

n Parking: Conference attendees can park in Lot 21 and walk past the gym and the stadium to get to McDonnell/Jadwin. They can also take the TigerTransit East Line shuttle from Lot 21 to South Campus.

This will drop them right outside McDonnell/Jadwin. The East Line shuttle runs from 5:00 a.m. to 7:00 p.m. After the reception at Frick, participants will have to walk back to Lot 21.

East Line Shuttle Route: http://www.princeton.edu/transportation/ttroutes/ http://www.princeton.edu/transportation/TTRouteMap.pdf

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Individuals attending the reception at Prospect House, can move their cars to Lots 10 and 13 on Williams Street after 5:00 p.m. when the lots become available to the public. If they move them at 4:30 p.m., they could get a ticket as those lots are highly patrolled.

Chartered shuttles will run from Prospect House back to Lot 21 at the end of the reception.

NYSCC Rheology Symposium Hotel Information Chauncey Conference Center

Homewood Suites

by Hilton

Courtyard by Marriott Princeton

One Chauncey Road Princeton, NJ 08541 Tel: (609) 921-3600

Princeton 3819 U.S. 1 South Princeton, NJ 08540 Tel: (609) 720-0550

3185 US Route 1 at Mapleton Road Princeton, NJ 08540 Tel: (609) 716-9100

Upcoming 2013 NYSCC Events Calendar • For updated NYSCC information, visit us on the web at: www.nyscc.org • For National SCC information: www.scconline.org April 23 Plant Science Seminar, Seasons, Washington Township, NJ May 12 Cosmetics in Contemporary Brazil, Renaissance Woodbridge Hotel, Iselin, NJ May 13-14 NYSCC Suppliers’ Day, Edison, NJ June 5 2014 NYSCC Antioxidant Symposium, New York, NY July (TBD) Golf Outing (TBD) September (TBD) NYSCC Regulatory Symposium (TBD) September 18 Culinary Event (TBD)

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Companies Participating in the Poster Session and Instrument Demonstrations

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he NYSCC would like to express its sincere gratitude to poster session and instrument demonstration participants. Without your company’s involvement and the financial support from our annual Suppliers’ Day Trade Show we would not be able to continue to provide our members with these types of educational programs at such bargain prices. Events like the full-day NYSCC symposiums could easily cost $1,000 per attendee without the income received to fund such projects.

The Soul & Science of Beauty. www.evonik.com/personal-care

NYSCC Rheology Symposium Committee

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edicated to the advancement of cosmetic science, the Society of Cosmetic Chemists* strives to increase and disseminate scientific information through meetings and publications. By promoting research in cosmetic science and industry, and by setting high ethical, professional, and educational standards, we reach our goal of improving the qualifications of cosmetic scientists. Our mission is to further the interests and recognition of cosmetic scientists while maintaining the confidence of the public in the cosmetic and toiletries industry.

The NYSCC takes this opportunity to expresses its gratitude to those companies whose employees volunteered much of their personal time to the success of the 2014 Rheology Symposium. Without such dedicated volunteers it would be impossible to achieve the SCC’s goals and mission statement.

NYSCC Educational Committee Chair • Cathy Piterski – Essential Ingredients

Rheology Symposium Committee • Joseph Albanese – 3V Inc. – Symposium Chair • Daphne Benderly – Presperse Corporation – Symposium Co-chair • Daria Long – Inolex – Catering • Steve Fantano – Mobius Sales Group – Poster Session • Bruce Kaduk – 3V Inc. – Poster Session • Daphne Benderly – Presperse Corporation – Instrument Demonstrations • Roger L. McMullen – Ashland Specialty Ingredients – Peer-review committee • Timothy Gillece – Ashland Specialty Ingredients – Peer-review committee • Jenna Jelinski – Extracts & Ingredients, Ltd. – Hotel & Travel • John Carola – Protameen – Registration *Not a SCC member yet? Get on board! Download an application at: http://www.scconline.org/website/about_scc/application/scc_member_application.pdf.

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Grow with the Flow: The Importance of Rheology in Product Development, Processing, and Quality Control

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any of our projects start with a question: “We have several products that were formulated to have the same viscosity—so why are they so different when we apply them?� or “Our product settles/separates over time. Can we prevent it?� or “We have two similar formulations. One regains its viscosity after application while the second formulation does not. Why and how can we fix it?�

To answer these questions, we have to understand that everything flows when an external force, including gravity, is applied to our system. If we properly characterize the flow properties of the system, the answers would follow. Rheology— the science that studies how materials deform and flow under the influence of external forces—provides us the tools to do so. The name rheology comes from the Greek word rheo, which means flow. In 1929, M. Reiner and E.C. Bingham introduced a new scientific discipline when they formed the Society of Rheology.1 They were inspired by a quotation attributed to Heraclitus: “Everything flows� (in Greek: panta rhei), which became the motto of the Society of Rheology. Plato paraphrased this observation as “Everything changes and nothing stands still.� Actually, the study of flowing systems can be traced back to Archimedes (~250 B.C.), Hooke (1678), Newton (1687), Stokes (1845), Maxwell (1867), Boltzman (1878), Einstein (1906), Trouton (1906), and many other scientists, who continuously expanded our knowledge from theory to application.2 We also have to understand that viscosity is not just a number, but should be characterized by a curve covering the relevant storage, processing, and application range, and that time plays an important role in the behavior of our products. In addition, temperature, pressure, and other factors affect the flow behavior of our products. Understanding the flow properties and the interaction of various ingredients in our complex formulations may explain why these systems behave the way they do and how can we modify them to formulate new and improved products.

We also should be aware of the time scale of the system compared to the time scale of the observation/experiment. If we measure changes that take a very long time, our experiment should run a very long time—see, for example, the pitch drop experiment at Queensland University, Australia that started in 1927 and is still ongoing.3 The ratio of the time scale of the system (tc), the stress relaxation time (also known as the Maxwell relaxation time), to the time scale of the observation (tp), was defined by M. Reiner as the Deborah Number —based on a line from Deborah’s biblical song: The Mountains Flowed Before the Lord, which is found in Judges 5:5.1 Luckily, most of our systems, especially those that are water-based, have very fast relaxation times.

n Flow Curves

As we apply a product to a surface, we may visualize it as occupying the volume between two plates while an external force is moving it in a certain direction. Assuming that the bottom plate is stationary, and the flow is laminar, the upper plate length (l0) is displaced by dl and the thickness (x0) by dx. We define the effect of the external force as pressure or shear stress (Ďƒ). If an external force (F) is applied to an area (A), the shear stress is Ďƒ = F/A. The shear strain (Îł) is defined as the relative change in the length of the material due to the external force: Îł = l/l0. If the top plate is moving at a velocity (v), the velocity gradient is defined as the shear rate (γ•), where γ• = dv/dx. For example, if we mix a product at a speed of 23 m/s, and the thickness of the affected layer is 33 cm, the shear rate would be 23/0.33 = 69.7 s-1. If we apply a product at a speed of 75 cm/s, and the resulting layer is 75 microns thick, the corresponding shear rate would be 75/0.0075 = 10,000 s-1.

It was Newton who discovered that in an ideal fluid, which we now define as a Newtonian Fluid, the stress is related directly to shear rate and the coefficient Ρ is a measure of the resistance of the material to flow—its unique viscosity. In other words, Ďƒ =Ργ• . Since the coefficient is constant for Newtonian Fluids, their viscosity is independent of the shear rate.

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Grow with the Flow

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(Continued from page 9)

Most fluids, however, are not Newtonian (Non-Newtonian Fluids) and their viscosity is not constant, but rather changes as a function of shear rate. Many fluids demonstrate a decrease in viscosity as a function of increasing shear rate. These materials are called pseudoplastic materials. The “structure” in these systems is broken down under the external force, resulting in shear thinning behavior. If the inter-particle association is

Figure 1: flow curves

strong, the system may behave like a solid at rest. The initial stress that is required to overcome the internal forces and disrupt the structure of the material is defined as the yield value. Yield values may be determined by direct measurements, or by interpolation of the stress to zero shear rate using mathematical models.

Materials that exhibit a yield value and, then, shear thinning with increasing shear rate, are defined as plastic fluids. Some systems exhibit shear thickening with increasing shear rate and are defined as dilatant fluids. After measuring the relevant shear stress and shear rate, we may plot either the viscosity or the shear stress as a function of shear rate (Figure 1).

If we plot viscosity as a function of shear rate (Figure 2) for the formulations mentioned in the first question, we see that they crossover at about 20 s-1. This is probably the shear rate at which the initial measurement determined that the viscosity of both systems is the same. However, System A exhibits higher viscosity at low shear rates while System B produces higher viscosity at high shear rates. This behavior may be critical to their respective properties during storage (System B may be prone to settling), application (System A may result in a thinner layer), and recovery after application (System A may recover faster and to a more textured structure).

Figure 2: flow curves When the external force is removed, the initial conditions will be restored over a period of time—most systems should recover their “structure.” We therefore should measure the viscosity not only as a function of increasing shear rate (“up” curve), but also as a function of decreasing shear rate (“down” curve) after the inner “structure” has been broken down. If the “structure” recovers fast, the “down” curve would be superimposed on the “up” curve. In many cases, it takes time for the fluid to regain its structure and therefore the “down” curve would be below the “up” curve. We define thixotropy as Figure 3: thixotropic loop the ability of the system to exhibit shear thinning with increased shear rate AND slower recovery with decreasing shear rate (Figure 3). If the “up” and “down” curves overlap, the material is non-thixotropic. If the “down” curve is above the “up” curve, the material is rheopectic.

Another way to evaluate how the system rebuilds its “structure” with time is to follow the decrease in viscosity at a constant shear rate as the structure is being broken down, followed by the recovery of viscosity at a much lower shear rate.

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n Dynamic Properties

PTFE Additives for Personal Care Products

While an “elastic” system behaves like a spring, ideally gaining all of its initial energy as the external force is removed, a “flowing” (or “viscous”) system, such as water, would lose all of its energy when the external force is removed. Most systems exhibit a combination of elastic and viscous behavior and therefore are defined as viscoelastic materials. We can calculate the elastic component—the storage modulus (G’)—and the viscous component—the loss modulus (G”)—by a simple oscillation experiment that applies a certain strain to the system while oscillating it at a given frequency. In a typical strain sweep, the moduli (G’ and G”) are measured as a function of increasing strain at a constant frequency. On the other hand, the moduli are measured as a function of frequency at a constant strain in a typical oscillation sweep. Another way to evaluate the response of the system at low strains is a creep test. In a typical experiment, the system is extended at a constant stress while the resulting strain is measured as a function of time. This test may be extended to add the recovery process so that when the strain reaches a plateau, the stress is removed and the recovery is monitored as a function time. We use Silly Putty to demonstrate how the same material may exhibit elastic behavior under one set of parameters and flow under a different set of circumstances. A demonstration of the properties of a pool filled with cornstarch/water may be seen in a video clip from the Spanish TV show El Hormiguero (The Anthill).4

n Instrumentation

There are a variety of instruments that can measure the rheological properties of complex systems. Any instrument capable of measuring the relevant range of stress, strain, shear rate, viscoelastic properties, and, of course, records the temperature (and if required, the pressure) would qualify. There are many types of low cost, one-point measurement instruments that may give us an indication where we are, but would not enable us to calculate the absolute viscosity or the viscoelastic properties. Rotational and oscillatory rheometers that provide a range of strains and frequencies may provide the proper insight into the forces that control our formulation.

Some rheometers are based on controlling the stress while others are based on controlling the shear rate (by controlling their speed). With today’s advanced computer calculations, the information is analyzed and reported either as a graph or as a table, showing the various parameters. A variety of fixtures (sometimes referred to as sensors) are used to simulate the movement of a stationary surface and a rotating surface. These include concentric cylinders, cone and plate, parallel plates, and specially designed fixtures. Rheometers that provide a full range of shear stress, shear rate, oscillation, and analysis capabilities are relatively costly but they allow the user to analyze the information in a fraction of the time. Many instruments are specifically designed for quality control, process control, materials with very low viscosity, materials with very high viscosity, and for melt viscosity. A new class of rheometers offers a combination of techniques, for example, a combined rheometer and microscope to monitor the movement of particles or changes in phases during application.

When investigating which rheometer would be adequate for your system, we recommend preparing a long list of your needs and comparing it to what the rheometer system offers (including affordable price).

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Rheomer® 33T Higher clarity suspending polymer Contact: 888-776-7337 NovecareCC@Solvay.com

n Rheological Additives

Addition of just 0.1-0.5% of a rheological additive (i.e. a thickener or rheology modifier) to a complex formulation may significantly change the flow properties of our system. There are plenty of rheological additives to choose from. They may be natural or synthetic, low molecular weight or very high molecular weight, or organic or inorganic. Understanding the interactions of the rheological additive and the other ingredients in our formulation is crucial since some interactions may enhance the formation of a network structure while other interactions may impede the formation of a structure. The effect of the concentration of the rheological additive, its interactions with surfactants and salts, as well as the effect of pH, may significantly alter the flow profile of the system. We often use these interactions to our advantage by combining two or more rheological additives to achieve a required flow profile.

n Rheology and Product Development

Measuring the rheological properties and understanding the flow behavior of a system are the first steps in developing new products and modifying existing products. Ideally, one should be able to correlate the rheological properties, the structure of the system, and the application properties. We recommend a combination of the following tests: flow curve, thixotropy loop, flow recovery, creep/recovery, strain sweep, frequency sweep, dynamic recovery, and temperature scan together with a ladder study of the ingredients that may affect the flow properties of the system. We should keep in mind that while compositions may be formulated to achieve similar effects, and therefore are hypothetically supposed to behave similarly, their rheological properties might be significantly different.

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Rossow USA, Inc. Specialty Cosmetic Ingredients

Grow with the Flow

Cosmetic ingredients your formulas can trust!

Contact: www.rossow-usa.com www.rossow-usa.com +1 (855) 7ROSSOW contact@rossow-usa.com

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n Conclusions

Characterization of the rheological properties of complex systems and understanding the interactions between the components of the system enable us to develop new products and improve the processing and quality control of existing products. Characterization is quite easy due to the modern advanced technology and computerized instrumentation. A variety of tests are available to probe the rheological properties of the products and should allow us to focus on the ingredients that affect them most. The wide range of rheological additives enables us to tailor our formulations to exhibit a target product profile to meet the demands of an ever changing marketplace. The science of rheology advances very fast and adds to our understanding of the behavior of complex fluids. Today’s research expands to foams, sprays, extensional forces, and more as well as to the development of new techniques and combination of techniques to characterize the flow properties of the system. All you need to do is to bear in mind that everything changes and nothing stands still—to think “rheo” logically and Grow with the Flow.

n References

1. M. Reiner, “The Deborah number,” Physics Today, 17(1), 62-63 (1964).

2. D. Doraiswamy, “Origins of rheology: a short historical excursion,” Rheology Bulletin, 71, 7-17 (2002).

3. R. Edgeworth, B.J. Dalton, and T. Parnell, “The pitch drop experiment,” Eur. J. Phys., 5, 198-200 (1984). (www.physics.uq.edu.au/physics_museum/pitchdrop.shtml) 4. http://www.youtube.com/watch?v=f2XQ97XHjVw. 5. Rheology Handbook, A Practical Guide to Rheological Additives, Elementis Specialties, Inc. 6. D. Laba, Rheological Properties of Cosmetics and Toiletries, Cosmetic Science and Technology Series, Vol. 13, Marcel Dekker: New York, (1993).

7. H.A. Barnes, J.F. Hutton, and K. Walters, An Introduction to Rheology, Elsevier Science: Amsterdam (1989).

8. F.A. Morrison, Understanding Rheology, Oxford University Press (2001).

9. C.W. Macosko, Rheology Principles: Measurements and Applications, Wiley/VCH: New York (1994).

About the Author:

D

r. Hemi Naé is President, Hydan Technologies, Inc., a consulting company in Hillsborough, NJ. Dr. Naé has over 25 years of academic and industrial experience in rheology, rheological additives, product development, and formulation. He is the author of 16 patents and 33 technical publications. Hydan Technologies holds public and in-house “Practical Rheology” courses. Dr. Naé can be reached at (609) 423-4164 (office), (609) 577-8060 (cell), or hemi@hydan.com (e-mail).

The Hitchhiker’s Guide to Rheology

…Tim Gillece

I

n Douglas Adams’ classic science-fiction novel, The Hitchhiker’s Guide to the Galaxy, the protagonist, Arthur Dent, abandons the comforts of his predictable life to become an interplanetary hitchhiker only minutes before the Earth is obliterated.1 With only his alien friend and a sophisticated, electronic, instructional guidebook to show the way, he travels through time and space in the pursuit of adventure and the meaning of life. Although under much less dramatic circumstances than those experienced by Arthur Dent, recent changes at work created an opportunity for me to leave my comfortable place in life to pursue other challenges. That is, I recently left my decade-long polymer synthesis position to spend more time on applications-based projects involving explorations into the complex world of rheology. However, to my chagrin I have yet to find a rheologically savvy alien or a condensed version of The Hitchhiker’s Guide to Rheology to concisely reveal the answers to my many questions.

In the past several months I have read many approaches to educational discussions on rheology—which is vaguely defined as the study of the deformation and flow of matter.2 And, in my humble opinion, a common thread is that beyond the pages of the Introduction, most of the textbooks on

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rheology are far too esoteric for the rushed, industrial scientist to quickly digest. However, the fault for this conspiracy cannot be entirely blamed on the pedantic ramblings of “geeky,” overeducated authors. The truth is that rheology is an inherently difficult subject because it is complexly built on the foundations of mathematics and physics; yet, to fully appreciate its use in linking molecular structure to product performance requires intimate knowledge of the end-use application, an abundance of testing experience, and the imagination to interpret the results.

So, based on these daunting revelations, you can see why this “rheological hitchhiker” has lately developed a “healthy” addiction to strong antacids and a variety of over-the-counter analgesics.

Warning: This text should not be confused as a feeble attempt to develop a comprehensive rheological guidebook! Instead, the intent is to present to beginners a newbie’s view on three rheological destinations. Consequently, because my words are targeted directly at the inquisitive rheological hitchhiker, I shall now kindly ask all of the advanced rheology wizards to flip to another page of the Cosmetiscope! Finally, in the spirit of Douglas Adams, I have a message to all hitchhikers that wish to continue reading: “DON’T PANIC.”

n Destination 1: Shear Rate and Viscosity Until recently I had not fully understood any of the advantages of a rheometer over a less costly viscometer.3,4 Why? Because the only rheological product specifications directly associated with my synthesis job were 25 oC, one-point viscosity measurements by capillary or spindle-type viscometry. From a quality control perspective, this information was perfectly sufficient. But, is a one-point viscosity measurement always an adequate indicator to predict the performance of a product in the associated application? The following hypothetical example describes a situation where the answer is “No.” Let us assume that all of the properties of a hairspray fixative (Lot B), including the one-point viscosity, fall within the specifications and that the QA Manager justifiably releases the product for delivery to the customer. Nevertheless, three days later the livid customer complains because a 2,000 gallon batch of the 55% VOC hairspray product containing Lot B failed applications testing. Apparently the batch made with the new material sprayed well, but dripped miserably during spraypattern testing. What the heck happened? After reconfirming the lot is within the specifications, the QA Manager submits Lot B along with a control, Lot A, to the rheologist for a more detailed comparison of their flow behaviors.

Figure 1: Viscosity Curve for Two The viscosity profiles (Fig. 1) of the two fixative lots, which Hypothetical Hairspray Fixatives were generated by a rotational Cone-and-Plate rheometer, tacitly emphasize the need to understand the intricacies of your application. Observe that both lots are shear thinning, indicating that they drop in viscosity with increasing shear rate, and that Lot A has a higher viscosity at lower shear rates (points 1 and 2), yet a slightly lower viscosity than Lot B at higher shear rates (points 3 and 4). Further, note that the product specification, which was based on Lot A, calls for measuring a one-point viscosity with a lower cost, spindle-type viscometer at a shear rate that is, coincidentally, at exactly the shear rate where the two viscosity curves cross over. Basically, without initially testing the supposedly identical lots at a range of shear rates paralleling those seen in the real application, it would have been very difficult to fully predict the differences in applications performance. Hence, although both systems sprayed sufficiently, the more detailed data confirmed the validity of the customer’s complaint by verifying that the lower shear rate viscosity of Lot B was too low to resist the typical shear rates introduced by gravitational forces. Most importantly, the data aided in properly shifting the cause to a processing deviation that occurred during the polymerization of Lot B.

n Destination 2: Dynamic Data

In the hypothetical viscosity measurements discussed above, the flow data was collected during a test that steadily rotated the Cone-and-Plate geometry in a clockwise direction. Flow measurements are important; but, if you are interested in the viscoelastic properties of your materials, Dynamic Mechanical Testing methods should be applied. In short, a sinusoidal strain (or stress) is applied to the sample and the corresponding sinusoidal stress (or strain) response is measured. The resultant relationship between these input and output waves describes the viscoelasticity, or the amount of solid (elastic) and liquid (viscous) character intrinsic to the material.

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Dynamic studies are important tools for understanding the time-dependent performance of viscoelastic materials, such as forecasting the storage stability of intrinsically unstable dispersions or monitoring in situ gel formation.5 For example, an oscillatory experiment termed a Dynamic Time Sweep (Fig. 2) was used to hone in on the optimal composition of a formulation by probing the change in viscoelasticity of an antiperspirant (AP) complex as a function of time. Briefly, the formulation consists of traditional AP salts and polymers that interact under the correct conditions to form gels that progressively stiffen as a function of time. By appropriately formulating the salt-to-polymer ratio to control the gel time and gel strength, hotroom studies have suggested that it is possible to enhance the sweat reduction efficiency of an AP salt by forming reinforced plugs inside the sweat glands.

Figure 2: Dynamic Time Sweep Curve In ratios A and B (Fig. 2), the elastic modulus (G’) increases and for Two Antiperspirant Formulations eventually crosses the viscous modulus (G”) at the gel point, where G’ = G” (Gc). Further, note that Ratio A has a higher Gc and quicker gelation time than Ratio B, indicating that Ratio A forms a much stiffer gel in a much shorter time than Ratio B. Unfortunately, the high level of immediate gel formation in Ratio A hinders migration of the complex into the pore, thereby decreasing sweat reduction efficiency and increasing the level of unwanted “pilling” of the complex on the skin surface. In contrast, along with having a much lower gel strength (lower G’), the gel point of Ratio B is 20 minutes later than Ratio A, suggesting that the gel complex has more time to enter a sweat gland before forming a rigid plug.

n Destination 3: Yield Stress of Structured Liquids

In viscoelastic materials, the yield stress is defined as the minimum stress needed to induce flow— which implies that something designated with a yield stress does not flow until a sufficient amount of force is applied to it. Structured liquids such as ketchup, toothpaste, paint, hair gel, mayonnaise, and even orange juice have been tagged with yield stress values. That said, many experts believe that terming “yield stress” to structured liquids is a bit misleading.6 Why? You can start by randomly blaming the biblical figure, Prophetess Deborah, for coining, “…and the mountains flowed before the Lord.” So, if mountains gradually flow—and they do— then it should be no surprise that softer, more compliant materials, such as your favorite hair gel, also flow if given enough time. In a very small nutshell, nearly everything eventually moves if you stare at it long enough. The good news is that, although the term “yield stress” may be somewhat of a misnomer when applied to viscoelastic materials, reported yield stress values are nonetheless meaningful for correlating resiliencies such as a formulation’s initial resistance to creaming, sedimentation, and destabilization caused by vibrations sustained during transportation.7 Figure 3: Hypothetical Flow Curve for a Structured Fluid Rationally speaking, although structured liquids gradually flow, the change in viscosity below some critical stress is very small and the material behaves solid-like (Fig. 3, Region A). However, at the onset of some critical stress (Fig. 3, Region B) the structure begins to break and greater fluid-like flow ensues until a minimum viscosity plateau is reached (Fig. 3, Region C). The results from one of the many yield stress methods, such as the hypothetical flow data shown in Figure 3, are then extrapolated or fit to rheological models to assign a yield stress value that singularly describes this sudden transition to liquid-like behavior.

OK…stand and clap for yourself if you knew why the words “many yield stress methods” were purposely italicized in the last paragraph. For the rest of us, a very general list of yield stress methods includes the (1) Stress Ramp, (2) Dynamic Stress or Strain Sweep, (3) Extrapolation or Model Fitting of flow data, and (4) Incremental Creep Test; and, to complicate things, variations in testing conditions, such as the temperature, shear rate, stress ramp rate, etc., can affect the yield stress result from each of these tests.

Further, because the current state of any structured 14

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fluid may be irreversibly dependent on the number of times it is handled, even greater care must be taken when preparing, conditioning, and testing delicate yield stress fluids such as suspensions and emulsions.8 From my reading, here are a few useful guidelines to get more accurate and reproducible yield stress results: 1. Treat your samples, especially your sensitive samples, with extreme care!

2. Use the same preparation, conditions, and yield stress method for all samples in your study; and, only directly compare to literature results that used the same methodology.

3. Report your results with the chosen yield stress method and testing conditions.

This concludes your hitchhiking tour through a very tiny fragment of the universe of rheology.9 Hopefully, you have enjoyed the voyage and have retained a few mental souvenirs from the trio of rheological destinations.

If the late Douglas Adams had actually written A Hitchhiker’s Guide to Rheology, he probably would have concluded the work by philosophizing that learning rheology tends to pass through three distinct and recognizable phases: Survival, Inquiry, and Sophistication, otherwise known as the Stress, Strain, and Hernia phases.

Quite frankly, I am not looking forward to the third phase. n REFERENCES: 1. Douglas Adams, The Hitchhiker’s Guide to the Galaxy (Pocket Books, 1981).

2. http://www.thefreedictionary.com/rheology.

3. Dr. Hemi Naé, Short Course: Practical Rheology, http://www.rheologyadvantage.com (June 20-21, 2007, Princeton, NJ).

4. Hemi Naé, “Introduction to Rheology,” in Rheological Properties of Cosmetics and Toiletries, Dennis Laba (Marcel Dekker, 1993).

5. Philip E. Miner, “Emulsion Rheology: Creams and Lotions,” in Rheological Properties of Cosmetics and Toiletries, Dennis Laba (Marcel Dekker, 1993).

6. H.A. Barnes, A Handbook of Elementary Rheology (The University of Wales Institute of Non-Newtonian Fluid Mechanics, Aberystwyth, 2000).

7. TA Instruments: Rheology Training Course Presentation (June 2007, New Castle, DE).

8. Q. Nguyen, T. Akroyd, D. De Kee, L. Zhu, Yield stress measurements in suspensions: an inter-laboratory study, Korea-Australia Rheology Journal, 18, 15-24 (2006).

9. Thank Q.

About the Author:

T

im Gillece received a B.S. in Chemistry from William Paterson University in 1995, and an M.S. in Chemistry from Seton Hall University in 1998. He is currently a Scientist in Ashland Specialty Ingredient’s Materials Science Department.

Formulating with Rheology Modifiers

…Joseph Albanese

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et’s pretend for a moment that you are a novice cosmetic chemist working in product development. You are asked to develop a new product. (That’s what people do in product development.) For any number of reasons your first attempts are rather disappointing and your group leader suggests that you try a different rheology modifier. At which point you ask a colleague, "What do I need a rheology modifier for anyway?", and you learn that rheology modifiers do many things.

Rheology modifiers do more than just thicken. According to Stokes' Law, higher viscosities also predict greater emulsion stability.

They also increase yield value, a measure of a materials resistance to flow, which is so important for creating stable suspensions and homogeneous distribution of active ingredients throughout the course of the product’s shelf life. They minimize the effects of temperature change on viscosity; thus maintaining product consistency. They enhance product aesthetics and many provide a nicer skin feel. They allow for easy dispensing of products from their packaging and application to the body giving improved coverage and homogeneous distribution of (Continued on page 16)

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active ingredients like sunscreens for better skin protection. Some rheology modifiers also are film-forming resins and act as styling ingredients for hair or may provide water resistance claims for sunscreens. Many generate structural integrity to gels and solid stick forms. Many are also used to provide leveling, a term used in the paint industry to describe the phenomena which allows for the disappearance of brush strokes. Obviously, leveling is an important property for nail polishes but it is also important for sunscreens, so that after they are applied they may also continue to flow into the crevices and creases of skin. All of these benefits seem rather important and convince you that it is wise to follow your group leader’s advice if you want to successfully complete your project and hold onto your job.

Because you are not sure of all the ingredient choices that exist, you refer to the INCI Dictionary for a listing of available rheology modifiers. What you discover is that the function classification “Rheology Modifiers” does not exist in the INCI Dictionary. You do, however, manage to find the following four categories: Viscosity Controlling Agents, Viscosity Decreasing Agents, Viscosity Increasing Agents for Non-Aqueous Systems, and Viscosity Increasing Agents for Aqueous Systems. What are these Ingredients? The INCI Dictionary lists 39 Viscosity Controlling Agents, 101 Viscosity Decreasing Agents, 531 Viscosity Increasing Agents for Non-Aqueous Systems, and 496 Viscosity Increasing Agents for Aqueous Systems. Oh boy, so many choices, where does one begin? Even though all of the ingredients in each of those four functional classes affect product viscosity, many of them (ingredients Figure 1: The stability of suspensions, emulsions, and foams are like long chain fatty alcohols, salts, perfumes, acids and bases, surfactants, etc.) partially predictable from Stokes’ Law—one mechanism by which rheology modifiers enhance product stability. An are not normally considered rheology modifiers. So what is?

Here are some ingredients formulators typically think of as rheology essential goal in formulating is to have a slow settling velocity (V), which means the denominator (viscosity) modifiers used to increase viscosity. For non-aqueous formulas, there are needs to be large. organoclays, polyethylenes, Al/Mg hydroxystearate, and trihydroxystearate. For aqueous systems, there are gums, cellulosics, and clays. Polyethylene glycols, silicas, and synthetic polymers are utilized in both non-aqueous and aqueous systems. This abbreviated list of ingredients simplifies your selection process a little, but there are still far too many options. To narrow the list further one needs to consider the type of formula being developed. Refer to your marketing brief. Is it a hair or skin care product?

Is it a gel, emulsion, foam, or surfactant-based cleanser? What are the finished product specifications (pH, viscosity, color, odor, appearance, etc.)? Does the formula contain electrolytes and/or any ingredients with anionic or cationic charge characteristics? What are the processing parameters and filling equipment used in manufacturing? Under what storage conditions (light, temperature) will the product be kept? You want to ensure homogeneous delivery of active ingredients. You need to know what type of packaging the product will be in and how will it be dispersed from the packaging (pump, aerosol, tube, jar). You want to be sure it applies easily with a good skin feel.

The rheology modifiers that function as Viscosity Increasing Agents (i.e. thickeners) may be either naturally or synthetically derived. Naturally derived ones may be either organic (plant or microbial) or inorganic. Organic rheology modifiers include polysaccharides, xanthan gum, alginates, cellulose, and guar gum. Inorganic rheology modifiers include smectite clays and amorphous silicon dioxide. Some examples of synthetically derived rheology modifiers include polymers of acrylic acid, polyethylene and related copolymers, alkylene oxide polymers and its esters, and methyl vinyl ether/maleic anhydride copolymer crosslinked with decadiene.

There are various types of rheological behavior. These include Newtonian fluids when the viscosity remains constant regardless of shear. Water, mineral oil, and glycerin are all Newtonian as are many shampoos. Non-Newtonian fluids may exhibit either shear-thinning or shear-thickening behavior.

Pseudoplastic and thixotropic materials are both examples of shear-thinning rheology, which is normally most desired in personal care products. Depending upon what you are trying to achieve, either timeindependent or time-dependent properties are most desirable. Pseudoplastic flow describes products that are shear thinning in which viscosity decreases with an increase in shear rate, then recovers immediately after the shear stops (time-independent). Pseudoplastic flow is typical of carbomer rheology modifiers and other polyacrylates. While thixotropic flow is also shear thinning, the recovery of viscosity requires a certain amount of time. Thixotropic flow is typical of clays and organoclays. Normally, dilatant and rheopectic products are

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not desired in personal care formulations because they cannot be easily dispersed from packaging or easily applied to the body. Dilatant materials immediately produce shear thickening while rheopectic products yield shear thickening over time.

Insufficient force to The factors affecting the settling velocity of particulates in a suspension/dispersion and induce flow the agglomeration or separation of dispersed droplets in an emulsion include both the properties of the suspended particle/droplet (count, size, shape, density, and charge) and the suspending medium or external phase (density, charge, rheology, and MW of suspending polymer).

Some examples of rheology modifiers with pseudoplastic properties include synthetic polymers (polymers of acrylic acid, carbomers, and hydrophobically modified polymers), gums (guar, hydroxypropyl guar, xanthan, and carrageenan), clays (hectorites, bentonites, Enough force to overcome and Mg/Al silicates), cellulosics (hydroxyethylcellulose and hydroxypropylcellulose), and yield value of the toothpaste silicas (hydrated silicas and fumed silicas). On the other hand, the most common Newtonian ingredient is polyethylene glycol. Some examples of rheology modifiers with thixotropic properties include gums (karaya and carrageenan), organoclays (quaternium-18 hectorites and bentonites, stearalkonium hectorites and bentonites, and disteardimonium hectorites), polyethylenes, silicas (hydrated silicas and fumed silicas), trihydroxystearin, and Al/Mg Yield Point (Pa) Viscosity (Pa¡s) hydroxystearate.

Honey 0 11.0 Eager to learn more about the applications of rheology modifers, you consult with some Ketchup 14 0.1 veteran colleagues at work as to the various options for specific types of formulations. For Mayonnaise 85 0.6 shampoos and body washes, viscosity is most inexpensively increased using NaCl. Increasing Figure 2: Yield value. the concentration of surfactants and adding auxiliary surfactants like cocamidopropyl betaine will also normally increase viscosity. Conversely, dilution with water will have the opposite effect.

In many cases, simple addition of salt will not achieve the desired viscosity. For cleansers with a low level of surfactant the peak viscosity of the salt curve will easily be exceeded before the desired viscosity is reached and sulfate-free systems just do not respond to salt addition in the same way. These difficult to thicken surfactant systems often call for the use of acrylates copolymer, acrylates/palmeth-25 acrylates copolymer, guar, hydroxypropylmethylcellulose, xanthan gum, PEG-150 distearate, or magnesium aluminum stearate.

Rheology modifiers often enhance foam and lather aesthetics. Reduced salt raises surfactant cloud point.

Remember to add fragrance prior to final pH and viscosity adjustments.

In creams and lotions, fatty alcohols and fatty acids in the oil phase contribute to base rheology. The stability and aesthetics can be greatly enhanced by adding a rheology modifier. For example, organoclays may be added to the oil phase. Polymeric emulsifiers (associative thickeners), carbomer, and hydrophobically modified carbomers are often added to the water phase. Addition of polymeric emulsifiers permits the formulator to reduce surfactant emulsifiers and often improves mildness and water resistance of 3+!4! sunscreens. !!

4!3+$%!!!

Rinse-off hair conditioners are purposely-low pH products for delivering better conditioning 56*(1)0,1+7(!)*896,-0'! benefits from the mono- and/or polymeric quaternary ammonium compounds present.

Besides fatty alcohols, they often contain oils and silicones for additional conditioning. Polymers :)2!;0<=*)! :-,8*),*=!

3*91)+6-B*=! requiring neutralization with base will not work in >-.?162!(0-6*=!! @00,*62!(0-6*=!

C0)*!6-'*+)!

A<066*'!?2=)0.*6,!

A<066*'!?2=)0.*6,! these low pH products. Moreover, anionic materials will be incompatible with cationic &'()*+,-'.!/-,(0,-12! conditioning agents. Nonionic polyacrylic acids, Figure 3: Thickening mechanism of carbomer. such as polyquaternium-37 and polyacrylate-1 crosspolymer (plus hydroxyethylcellulose), are good rheology modifiers that may be incorporated into conditioning systems. When using hydroxyethyl-cellulose, speed its dissolution with heat and make sure it fully hydrates before adding other ingredients.

Hair styling mousse contains film-forming polymers to provide hair with a desired set. Polyquaternium-37, cellulosics, polyquaternium-4, polyquaternium-10, polyquaternium-24, and PVP are frequently formulated into mousse products. These multifunctional additives provide styling, rheology, conditioning, foam stability, and !"!#$$%!

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other benefits. The foam should not become â&#x20AC;&#x153;too stableâ&#x20AC;? so that it is not easy to distribute through the hair. The choice of propellant and its concentration can also have a large impact on foam rheology.

Hair styling gels are almost always based upon carbomer as the rheology modifier. Other polyacrylic acids may be used as well as hydroxypropylcellulose. Hydroxyethylcellulose, on the other hand, tends to leave an undesirable tackiness. It is wise to partially neutralize carbomer before adding PVP or PVP/VA to optimize clarity. Use Na4EDTA and benzophenone-4. Be aware that Na4EDTA has pH > 10.5 and benzophenone-4 has pH < 2.5.

The following types of formulations present their own unique challenges. For hydroalcoholic formulas, the selection of the appropriate base is critical to successful thickening with carbomers. For thickening hydrogen peroxide-based formulas one must keep the pH below 5 in order to maintain hydrogen peroxide stability.

Formulating shampoos and body washes with non-formaldehyde donating preservatives, such as sodium benzoate and benzoic acid, require low pH for efficacy. In these low pH systems, it is recommended to use an acrylates copolymer that delivers peak viscosity and clarity at pH 4.5â&#x20AC;&#x201C;5.5. In order to avoid forming insoluble complexes, one must be cautious of cationic/ionic charge incompatibilities. Thickening oils with anything other than organoclays often involves delicate mixing conditions and/or high processing temperatures. Often times the rheological properties are not perfect. Polyacrylic acids will not thicken non-aqueous systems.

About the Author:

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oe Albanese is currently the Technical Marketing Manager Personal Care at 3V Inc. During his career in the personal care industry Joseph Albanese worked for Avon, Shulton, and Colgate-Palmolive in both process and product development groups. His employment on the supply side of the industry included more than 12 years at GAF/ISP where he went from formulation chemist to manager of the Hair Care Applications/ Tech Service lab. He is a graduate of the F.D.U. Cosmetic Science M.A. Program. He has been a member of the SCC since 1984 and was the 2010 Chair of the New York Chapter.

Rheology, Theology, Salvador Dali, and God â&#x20AC;ŚJoseph Albanese

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o, this is not going to be one of those childrenâ&#x20AC;&#x2122;s games, such as â&#x20AC;&#x153;One of These Things is Not Like the Otherâ&#x20AC;? that you might still see on Sesame Street. Instead, rather than highlighting their dissimilarities, I will try to draw a connection between the very diverse elements listed in the title of this article.

n Rheology

As you probably already know, rheology is the science that studies the deformation and flow of materials. Theology is a way of thinking, or a belief systemâ&#x20AC;&#x201D;like an ideology, religion, etc.

Even though the derivation of both words may be traced back to the Greek words rheos (flow, stream), theos (God, god), and ology (a branch of learning), they are â&#x20AC;&#x2DC;seeminglyâ&#x20AC;&#x2122; two very different branches of learning.1,2 Now, your computer, which thinks it knows everything, will certainly confuse the two. Therefore, I caution you that the first time that you type the word â&#x20AC;&#x2DC;rheologyâ&#x20AC;&#x2122; using a word processer do not trust spell check to get it right. Invariably it will change the word to â&#x20AC;&#x2DC;theologyâ&#x20AC;&#x2122;. At least thatâ&#x20AC;&#x2122;s been my experience.

Like Sgt. Phil Esterhaus (played by the late, Michael Conrad) said at the end of every TV episode of Hill Street Blues, â&#x20AC;&#x153;Letâ&#x20AC;&#x2122;s be careful out there.â&#x20AC;? In fact, go ahead and add the word â&#x20AC;&#x2DC;rheologyâ&#x20AC;&#x2122; to your software programâ&#x20AC;&#x2122;s dictionary right now. I will wait.

As you will see in the next section, the connection between the two words runs so much deeper than 18

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the similarity of their spelling. The rheological realm covers a continuum that extends from purely viscous materials that deform or flow irreversibly (e.g., water, mineral oil, etc.) to purely elastic solids, that spring back unchanged (a steel ball, for example)—see Figure 1.3 Pure liquids exhibit Newtonian rheology and their viscosity remains constant regardless of the amount of stress applied. Most, if not all, materials are viscoelastic, which means that they contain varying degrees of both properties.

Take, for example, Silly Putty (Dow Corning 3179 dilatant compound). Under low shear stress it exhibits viscous behavior (will flow irreversibly) and elastic behavior under high shear (it will bounce or break; thus, behaving very much like a solid)— see Figure 2.4 So, technically speaking, selling Silly-Putty as the “real solid-liquid” is truth-in-advertising.5 It is very difficult to imagine a steel ball being elastic in nature. Under normal

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Figure 1. Rheology

Figure 2. Viscosity of Silly Putty. From http://www.campoly.com/general_research.html.

Modulus =

Shear Stress Shear Strain

Viscosity = Shear Stress Shear Rate Shear strain is a unit-less quantity, the relative displacement of the faces of a sheared body (for example a layer of fluid) divided by the distance between them.

conditions, certainly no one can perceive any deformation; at least not with the naked eye. That is because the relaxation time, following removal of the stress, is immediate. It is equally difficult to conceive that it contains any viscous component whatsoever. At the opposite extreme, the viscous behavior of window glass, which actually is a super cooled liquid at room temperature, is also very difficult to observe. This time it is because the deforming force of gravity on a vertical windowpane takes decades to occur.5 At this point, the connection to theology enters the discussion. Here goes…

n Theology

Many years ago, I read about the Deborah Number.6 (No, I did not forget to mention Deborah in the title. I purposely left her out so that you did not jump to the conclusion that there was something sordid going on between her and Salvador.) Unlike the Reynolds Number,7 another dimensionless value that Chemical Engineers use to describe the rheological mechanics of fluid flowing through pipes, hoses, and other conduits, the Deborah Number has a theological aspect. Yes, I mean theological—it is not a typo. The Deborah Number takes the science of rheology to a higher (theological) level.

In 1964 Markus Reiner called upon the bible verse, “The Mountains flowed before the Lord,” contained in a song by prophetess Deborah (Judges 5:5) celebrating a victory over a powerful enemy. Reiner used that biblical reference to name the phenomena that given sufficient time even the most rigid or unyielding materials, like a mountain, will flow.

Characteristic relaxation time of material Deborah Number = (1) Time scale of observation Basically, the above ratio shows that the rheology of a material depends upon two fundamentally (Continued on page 20)

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different characteristic times: 1. The intrinsic time it takes for a material to adjust to applied stress.

2. The time needed to run the experiment.

Therefore, the way a material flows is not merely a fundamental nature inherent in the material itself. It also has to do with the stress it is under and the length of time it takes to respond. A small Deborah Number typifies a viscous fluid with Newtonian flow properties. A high Deborah Number exemplifies a nonNewtonian material. The higher the Deborah Number the more elastic or solid-like the material is. If the experiment is designed to see how something responds when you whack it with a hammer, the time scale of observation (the denominator) will be very short and will obviously tend to increase the Deborah Number.

Conversely, a material with a longer relaxation time will have a higher Deborah Number also. To reiterate, all materials are virtually viscoelastic. If the Deborah Number is < 1, the stress is proportional to the viscosity times the shear rate and the material behaves most like a viscous liquid. If the Deborah Number is > 1, the stress is proportional to the modulus of rigidity times the strain and the material behaves more like an elastic solid. If the Deborah Number is ≈ 1, the material is very viscoelastic.5 There is one more dimensionless number used by rheologists that I merely want to mention. That is the Weissenberg Number. It helps define the viscoelastic nature of polymeric solutions. If you are a cosmetic chemist formulating at the bench, you have probably seen the ‘Weissenberg Effect’ yourself without knowing that there is a term for it (see Figure 3).8 Weissenberg number = Relaxation time X Deformation rate9 (2) Figure 3. The Weissenberg Effect.

From http://www.rwe.com/web/cms/en/55196/ rwe-dea/know-how/wietze-laboratory/.

Next, one (me) may use both the Deborah Number and the Pitch Drop Experiment to make the comparison to, and connection to, Salvador Dali (the surrealist painter from Catalonia, Spain) and God.10-13

n The Pitch Drop Experiment

My entire thought process on this subject started when I read about a momentous occasion in science that occurred in August 2013. It was the extremely exciting news (a bit of sarcasm) that another drop of pitch dripped! The “Pitch Drop Experiment,” for those few who still might not know (more sarcasm), is the longest running scientific experiment in the world. (To be completely honest, that alone was new news to me.) It is even in the Guinness Book of World Records.

Briefly, back in 1927, Thomas Parnell, a physics professor at the University of Queensland in Australia, melted some pitch (a.k.a. bitumen or asphalt) and poured it into a funnel. The point he was trying to make is that even something as rock-hard as bitumen will, eventually, flow like a liquid. Maybe this was already known, but he set up this experiment as a teaching tool to demonstrate it nonetheless. Although not readily obvious, pitch, like Silly Putty, is viscoelastic. Both will shatter if you hit them with a hammer. However, on the opposite end of the continuum, the fluidity of pitch takes a lot longer to observe. One can observe the deformation of Silly Putty due to the force of gravity in a matter of minutes. It takes a single drop of bitumen nearly a decade to form and drop. And if you blink, you might miss it when it does.

A similar experiment is running at Trinity College in Dublin, Ireland, but the pitch is somewhat different and, dare I say, a little bit runny. That experiment did not start until October 1944, and when it dripped on July 11, 2013, it was the first time a pitch drop was successfully filmed. If you Figure 4. are interested, the video is available on many websites. It is certainly The Pitch Drop Experiment. possible that perhaps a few shared pints of Guinness between rheologists might be at the root cause of this obsession with pitch.

The viscosity of water at 20 ºC is about 10-3 Pa·s. Taking into consideration that the viscosity of pitch is temperature dependent, scientists calculated that the average viscosity of the pitch used in this experiment to be on the order of 108 Pa·s. Crazy as it may seem (to me anyway), the effective viscosity of the Earth is on 20

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the order of 1020 Pa·s.10 Who thinks of measuring such things? It’s a far cry from using a Brookfield RVT viscometer with spindle number 4 at 20 rpm at 25 ºC for 1 minute to find out if my shampoo is within specification or not. For comparison purposes, my shampoo of 8,000 centipoise (cP or cps) may be converted to 8 pascal seconds (Pa•s). Isn’t it interesting that both Pitch Drop Experiments began decades before Markus Reiner invoked the Prophetess Deborah in 1964?

n Salvador Dalí

When I first heard the biblical phrase, “The Mountains flowed before the Lord.”

I never thought it implied volcanic eruptions and molten lava flow, or motion of the Earth’s tectonic plates. Only that perhaps nothing is permanent and a faith that God can indeed move mountains and vanquish even the most formidable of foes. Used in the context with which Markus Reiner intended, I understood he created the Deborah Number to try and explain the inherent rheological properties of materials. I wondered if the watches in Salvador Dalí’s paintings are not melting due to high temperature, but simply symbolic that everything eventually, given sufficient time, will flow before the Lord. Did Dalí study the science of rheology? Did he know about the Deborah Number; or, was he at least familiar with the phrase quoted from the bible? According to Wikipedia, the symbolism of the melting watches “suggest that time is relative and not fixed.”14 In any case, Dalí was also fascinated with the new science of quantum mechanics and was “inspired by Werner Heisenberg’s Uncertainty Principle.”

n God

Forget for a moment whether you are an atheist, agnostic, or true believer.

Whatever your perceptions or beliefs about God may be, it is irrefutable that we do not know all there is to know about everything. We are severely limited. Maybe one day we won’t be. Our time here on Earth is finite. We won’t be around long enough to observe and measure the time it takes for some materials (like mountains) to deform under stress and relax again. But maybe there is some unknown constant that always was and always will be—even long after we are all gone.

Figure 5. Graphs of data from the Pitch Drop Experiment.

The time it took to observe a pitch drop drip seems long enough. So then, how inconceivably long might it take a mountain to flow; how many eons? Does time and space as we measure it even continue to exist? How does God measure time? What value do you plug into the denominator of the Deborah Number equation? If a tree falls in the woods and no one is there to hear it, does it make a sound? If a drop of pitch drips and there is no one there to observe it, does it actually drip? Which gets me to thinking about Schrödinger’s Cat and the “observer effect.” Best to save that for another day. So you see, this really is an article about the esoteric pitch drop experiment. If I gave that away in the title, who would read all my musings that it prompted? No doubt you would read about that insignificant slow-moving drop observation and either disregard it or, come away stimulated by your own thoughts and ideas it generated.

Esoteric, maybe. But insignificant? I guess not. It seems to be at the center of everything. Well, it doesn’t explain the meaning of life, but at least it is at the center of this article.

In conclusion, if you want to become closer to God, be sure to attend the two-day NYSCC Rheology Symposium, March 19-20, on the campus of Princeton University. Be there or be square wicked.

n References

1. http://www.thefreedictionary.com/rheo-.

2. http://en.wikipedia.org/wiki/Theos.

3. J. Albanese, Formulating with Rheology Modifiers. Some figures are slides presented at SWSCC and CTSCC meetings. They are available on-line at: http://www.swscc.org/Albanese-FormulatingwithRheology Modifiers-SWSCCSuppliersDay8-23-12.pdf.

4. Viscoelasticity of Silly Putty: http://www.campoly.com/general_research.html.

5. J.F. Steffe, Rheological Methods in Food Process Engineering, Freeman Press, 1996, pp. 332-336.

6. M. Reiner, The Deborah Number, Physics Today, 17(1), p. 62 (1964).

7. R.G. Griskey, Chemical Engineering for Chemists, ISBN-13: 9780841222151, American Chemical Society, Publication date: 5/28/1997.

(Continued on page 22)

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Rheology, Theology, Salvador Dali and God ®

®

Specialty Silicones t Specialty Esters Delivery Systems Skin & Hair Moisture Complexes EXSYMOL S.A.M.: Silanols t Peptides GELYMA: Marine Cell Actives 201-825-8800 t www.biosiltech.com

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8. http://www.rwe.com/web/cms/en/55196/rwe-dea/know-how/wietze-laboratory/.

9. http://www.rheothing.com/2010/08/deborah-and-weissenberg-numbers.html.

10. R. Edgeworth, B.J. Dalton, and T. Parnell, The Pitch Drop Experiment, http://www.physics.uq.edu.au/ physics_museum/pitchdrop.shtml.

11. Months Between Drops: http://www.huffingtonpost.com/2013/05/01/pitch-drop-experiment-worlds most-boring-scientific-study_n_3187039.html.

12. http://en.wikipedia.org/wiki/Pitch_drop_experiment#University_of_Queensland_experiment.

13. http://www.nature.com/news/world-s-slowest-moving-drop-caught-on-camera-at-last-1.13418.

14. http://en.wikipedia.org/wiki/Salvador_Dal%C3%AD.

About the Author:

J

oe is currently the Technical Marketing Manager Personal Care at 3V Inc. During his career in the personal care industry Joseph Albanese worked for Avon, Shulton, and Colgate-Palmolive in both process and product development groups. His employment on the supply side of the industry included more than 12 years at GAF/ISP where he went from formulation chemist to manager of the Hair Care Applications/Tech Service lab. He is a graduate of the F.D.U. Cosmetic Science M.A. Program. He has been a member of the SCC since 1984 and is currently Area I Director. Coincidently, Joe visited The Dali Museum in St. Petersburg, Florida in December and he highly recommends it.

Mona Lissajous: Where Science Brushes Art

n Introduction

…Timothy Gillece

W

hile trying to discover new methods to enhance the description and performance ratings of hairstyling fixatives, we decided to employ our shiny and new strain-controlled rheometer to attempt solid-state rheology on treated hair tresses. As the resultant LissajousBowditch plots painted the screen with eye-catching, 3D-looking networks of curves reminiscent of those created with a 1976 Kenner’s Spirograph, I was elated to see that the technique differentiated some well known performance subtleties between analogous styling resins; however, admittedly, I was even more smitten with the mysterious elegance of the collection of spirals. And, I was the first of many. One by one, curious loiterers staggered by in lab coats, murmuring descriptions such as beautiful, impressive, publishable, and the most depressing of all—pretty. Pretty!

In actual fact, the unsolicited comments delivered from the white-coated vagrants echoed my sentiments exactly. Could anything affiliated with art and beauty correlate to meaningful science? Science is defined as “the observation, identification, description, experimental investigation, and theoretical explanation of phenomena.”1 Thus, as evidenced literally in the drab definition, apparently there is no connection to beauty and art in meaningful science. Or is there?

n What are Lissajous Plots?

Jules Antoine Lissajous was a 19th century French physicist that had a keen interest in visualizing vibrations—more specifically, simple and compound harmonic motion. Equation 1 describes simple harmonic motion, whereas the orthogonal coupling and subsequent visualization of two parametric equations (Equation 2) represents compound harmonic motion—generating a Lissajous plot; where Ai is the

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amplitude, ωi is the frequency, ψi is the phase angle, -ψi/ωi is the phase shift, and t expresses the time dependence of the wave(s). x(t) = Ax sin(ωxt + ψx) (1) x(t) = Ax sin(ωxt + ψx), y(t) = Ay sin(ωyt + ψy) (2) Building on work by Nathaniel Bowditch, Lissajous devised an apparatus to visualize the interaction of two sinusoidal waves (i.e. sine waves).2 This was accomplished by focusing a light beam onto a mirror affixed to a tuning fork of known frequency. The light was reflected from the first mirror and subsequently focused onto another mirror attached to a second tuning fork that was vibrating in a direction perpendicular to the first tuning fork. The resulting patterns were actually beautiful and quite striking. Practically speaking, Lissajous plots show the phase and amplitude relationship between two oscillating signals. Thus, via modern oscilloscopes, Lissajous patterns can be used to study interference in practical uses such as radio and recording applications…and, because dynamic mechanical analysis involves the introduction and subsequent measurement of a returning wave after interaction with a sample, Lissajous plots have been developed for applications in rheology.3 In rheology, Lissajous curves are formed by orthogonally plotting the stress(t) and strain(t) (or shear rate(t)) waveforms together in an x-y plot. By examining the shape of the curves, some assumptions can be made regarding a material’s structure. For example, when plotting stress(t) vs. strain(t), a perfectly elastic material will appear as a line, viscoelastic materials will portray elliptical shapes, and purely viscous materials will appear as a collection of concentric circles. Because many rheological applications of Lissajous curves involve transitioning a structured material from a solid-like state to a liquid-like state, the Lissajous profiles will initially appear as positively sloped lines or elongated ellipses before warping at higher strains to ellipses or distorted circles.

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Figure 1: Lissajous plot of mayonnaise.

Figure 2: Lissajous plot of honey.

n Large Amplitude Oscillatory Shear (LAOS)

One of the more advanced rheological techniques currently used to appreciate what transpires when a structured material is highly deformed (e.g., during spraying, coating, rub-in) is termed Large Amplitude Oscillatory Shear (LAOS). In brief, LAOS is a technique used to characterize the response of a structured system, such as a hair gel or structured food, to a large sinusoidal deformation. In contrast to results derived from the reversible or linear region (using Small Amplitude Oscillatory Shear or SAOS methodology), where the structure stretches, yet remains essentially intact, the stress response is not, mathematically speaking, sinusoidal—meaning that more complex mathematics must be used to fully describe the distorted wave shape of the stress signal being relayed from the structurally compromised sample. To very cautiously touch on the mathematics, Equations 3 and 4 are parametric equations that describe the stress response signal received from the sample. In the linear range, the application of a very small applied strain results in the return of a sinusoidal stress wave and Equation 3 applies for use in calculating typical parameters, such as the elastic modulus (G’); however, in the time domain of LAOS testing, the sample’s structure is damaged irreversibly and the resultant stress wave is best described by a frequency (ωi) and initial phase (δ, ψi) dependent function that includes a series of wave terms—or, a series of higher overtones (Equation 4).

Linear: τ(t) = τ 0 sin(ωt + δ) Non-linear: τ(t) = τ 1 sin(ω 1t + ψ1) + τ 3 sin(3ω 1t + ψ3) + ...

(3) (4)

In LAOS testing, extracting detailed parameters related to the elastic (solid-like) and viscous (liquidlike) components of the viscoelastic material can get even more complicated. One approach is to perform advanced Fourier transformations on the LAOS data to convert the raw data from the time domain (e.g., Equation 4) to frequency data (Discrete Fourier Transformation). In the frequency domain, traditional data, such as the elastic and viscous moduli, as well as more detailed information, such as coefficients extracted from the additional harmonics, may be used to develop correlations between the extracted, non-linear parameters and the morphing structure of the warping substrate.4

n Experimental Examples: Lissajous Profiles

The Lissajous data were acquired from transient, dynamic strain sweep experiments using an ARES G2 (Continued on page 24)

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strain-controlled rheometer and were subsequently processed using Trios software (TA Instruments, New Castle, DE). Hair tresses were probed with torsion rectangular geometry, and 40 mm SS parallel plates were used on the honey and soft solids (25 °C). To visualize the decay in structure, the applied strains spanned both the linear and LAOS regions of deformation.

Figures 1-3 are stress vs. strain rate Lissajous plots for mayonnaise, honey, and a commercial hair gel, respectively. Note that the trends in the stress(t) vs. strain rate(t) Lissajous plots are opposite to those of the stress(t) vs. strain(t) curves seen in Figures 4-6. That is, a straight line represents pure liquid-like or viscous properties, and a circle-like loop profile portrays greater elastic properties. For background purposes, mayonnaise, like tomato ketchup, is generally regarded as a non-Newtonian, Bingham plastic—meaning that mayonnaise will not flow until application of a critical stress— Figure 3: Lissajous plot of a commerical hair gel. the yield stress. The commercial hair gel is also a yield stress material. Finally, honey is a viscous, Newtonian fluid.

Notice how each curve, except that for honey, appears to move, or fan out, especially at higher shear rates. The shape and size of each loop, where each loop represents a single strain experiment, are related to the material’s apparent structural response to the applied deformation. The commercial hair gel and mayonnaise have concentric circle-like Lissajous profiles at moderate shear rates—meaning that the structure is changing, as evidenced by nonoverlapping loop boundaries, and that the samples are reacting somewhat elastically at the 1 Hz frequency. However, at high strains, mayonnaise conveys a very abnormal Lissajous shape as its boundary lines begin flattening and overlapping at stresses just beyond the yield stress—suggesting that its structural changes have approached equilibrium. Lastly, honey shows a constant slope with changes in shear rate— indicating it is a viscous fluid. In fact, the slope of the line is an excellent estimate of the steady-state viscosity (~5000 cP), as the slope is proportional to the complex viscosity, which is the viscosity (η*) measured during dynamic testing. As an added Figure 4: Lissajous plot of European bonus, by looking at the curves and assuming there is negligible slip between the virgin dark brown hair. sample and the testing geometry, the onset of dramatic loop span changes may cautiously be used to estimate the apparent yield stress values for the structured fluids. For example, our LAOS results suggest that ketchup, mayonnaise, and the commercial hair gel have estimated apparent yield stress values of 19 Pa, 83 Pa, and 18 Pa, respectively. See Reference 5 for a comparison to Brookfield data.

Figures 4-6 are stress vs. strain Lissajous plots for torsionally deformed hair, PVP K-30 treated hair, and PVP K-60 treated hair, respectively. For untreated hair, the profile and slope of each loop in the 30+ loops overlay, as expected, did not change. Further, each loop is nearly a straight line, thereby conveying elastic behavior. At linear strains (i.e. SAOS), the PVP K-30 treated tress also behaves elastically—as indicated by the dark retraces at the center of the system. However, at a first critical strain, the style begins to deform, as evidenced by loop shape bending and curve slope decreases. At a second critical strain, a gap forms in the overlapping ellipses—indicating the onset of style failure. PVP K-60 shows a similar profile; however, note that prior to style failure, the initial slope, which correlates with the stiffness of style in the linear region, is higher than that seen in PVP K-30 treated hair.

In summary, LAOS and Lissajous plots can be extremely useful tools for studying structural changes in viscoelastic materials. By visually inspecting the variations in the shapes and slopes of the Lissajous loops, one can cursorily estimate a sample’s reaction to non-linear deformation. Further, through more complex mathematical techniques, it is possible to use LAOS data to better appreciate the spectrum of viscoelasticity—thereby gaining knowledge about the detailed structure-property relationships occurring in non-linear deformation applications, such as spraying, coating, spreading, mixing, etc.

n A Somewhat Related Philosophical Addendum: The Merger of Art and Science

Per thefreedictionary.com, the definition of art is, “The expression or application of human creative skill and imagination, typically in a visual form, such as painting or sculpture, producing works to be appreciated primarily for their beauty or emotional power.”1 Key to the definition is the excerpt, “…application of human creative skill…”

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In the early 1500’s, Leonardo da Vinci painted the Mona Lisa, arguably still the most famous painting in the world today. Although technically breathtaking, in terms of da Vinci’s genius use of lighting and sfumato shading, one may question as to why a portrait of an arguably average-looking, 16th century woman in a traditional pose is still generally regarded as a standard of art 500 years after its inception.

Da Vinci was arguably the most well rounded genius to walk the earth. His immeasurable curiosity drove him to learn the intricacies of life and to master a diverse skillset, including anatomy, cartography, archaeology, music, metallurgy, geology, engineering, botany, sculpture, mathematics, painting…and even a venture into robotics.

Part of his genius was to learn each discipline without boundaries—that is, instead of compartmentalizing the countless skillsets, da Vinci would bring details from all disciplines into everything he did, enabling him to view the facets of the world in a unified way. Thus, for example, by bringing his keen eye and artistic mastery into seemingly incompatible disciplines, such as anatomy with engineering, or science with art and music, Leonardo was able to envision and invent things the world had not yet seen.

Therefore, by congruently bringing all of his mastery and life experiences to the Mona Lisa palette, perhaps da Vinci was able to create something so detailed and historically unique that enthusiasts still feel the need to study the minutiae of the painting and to wonder about its mysteries today.

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Figure 5: Lissajous plot of hair treated with PVP K30.

“The relation of art and science is a relation of opposites. The purpose of art is: from feeling to get to truth. The purpose of science is: from truth to get to feeling or emotion. But they are about the same thing, with different direction.”6 – Eli Siegel In conclusion, rather than accept the possibility that beauty and art are entirely Figure 6: Lissajous plot of hair treated superficial, I have decided to consult with the ghost of Einstein to rationalize as to why with PVP K60. a group of nerdy scientists impulsively considered Lissajous plots to be worthy of the term “beautiful.” Although the definition of science brings to mind a highly educated pack of robots toiling at the bench with rubber policemen, beakers, and well-stocked pocket protectors, the truth is that science is fully entwined in curiosity and creativity, which are requisite proficiencies for scrutinizing and unraveling life’s mysteries. Perhaps the true beauty in our Lissajous plots epiphany was not solely in the pixels and patterns being scribed on the computer screen, but rather in the cogs and gears that began spinning in each scientist’s brain as they searched through their life experiences to interpret something different, or not completely understood, in their own unique and inventive way.

“The most beautiful thing we can experience is the mysterious. It is the source of all true art and all science. He to whom this emotion is a stranger, who can no longer pause to wonder and stand rapt in awe, is as good as dead: his eyes are closed.”7 – Albert Einstein So, in conclusion, according to a Renaissance man, a scientist, a poet, and a bunch of nerds in white labs coats, it seems that science can indeed be…pretty.

n References

1. www.thefreedictionary.com/.

2. http://www-history.mcs.st-and.ac.uk/Biographies/Lissajous.html.

3. R.H. Ewoldt, A.E. Hosoi, and G. H. McKinley, “New measures for characterizing nonlinear viscoelasticity in large amplitude oscillatory shear,” J. Rheol., 52(6), 1427-1458 (2008).

4. “LAOS and FT Rheology Analysis Software,” TA Instruments presentation, TA Instruments, New Castle, DE. Thank you to Mike Delancy, Gregory Kamykowski, and Terri Chen for their technical insights.

5. http://www.brookfieldengineering.com/education/rheology_papers_yield_stress.asp.

6. http://www.aestheticrealism.net/lectures/Tro1451.htm.

7. http://rescomp.stanford.edu/~cheshire/EinsteinQuotes.html.

About the Author:

T

im Gillece received a B.S. in Chemistry from William Paterson University in 1995, and an M.S. in Chemistry from Seton Hall University in 1998. He is currently a Scientist in Ashland Specialty Ingredient’s Materials Science Department.

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Innovation for Hair & Skin

croda.com/na/pc

1.625 x 2.5 color

Save the Date June 5, 2014

New York Academy of Sciences World Trade Center, Building 7 â&#x20AC;˘ New York, NY The New York Chapter of the Society of Cosmetic Chemists is proud to announce the 2014 NYSCC Antioxidant Symposium, which will feature key academic and industrial researchers in the field of antioxidants and the skin. The conference will be held on the top floor of the newly constructed Building 7 of the World Trade Center, home to the New York Academy of Sciences. There will be a concurrent poster session in which entries will be eligible for the poster competition and will be judged on originality and innovation relevant to methodologies and the use of antioxidants in skin care.

Please send abstracts for podium presentation submissions by April 15, 2014, to Jenna Jelinski at jjelinski@morretec.com.

Calling for Poster Submissions

Conference attendees will receive a complimentary book:

Antioxidants and the Skin

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Antioxidant Symposium Featured Presentations Release of Polyphenols from Cosmetic Emulsions and their Permeation through the Skin – Olesya Zillich, Ph.D. (Fraunhofer Institute for Process Engineering and Packaging, Freising, Germany) ____________________________________________________________________________________________ Changes in Cutaneous Radical Scavenging Activity after Topical and Systemic Application of Antioxidants – Martina Meinke, Ph.D. (Klinik für Dermatologie, Venerologie und Allergologie, Berlin, Germany) ____________________________________________________________________________________________ Botanical Antioxidants for Health and Beauty of the Skin – Hasan Mukhtar, Ph.D. (Department of Dermatology, University of Wisconsin) ____________________________________________________________________________________________ Prevention of Ultraviolet Radiation-induced Oxidative Stress in the Skin by Dietary Phytochemicals – Santosh K. Katiyar, Ph.D. (University of Alabama at Birmingham and Birmingham Veterans Affairs Medical Center) ____________________________________________________________________________________________ Environmental Effects on Skin: Antioxidant Protection against Oxidative Challenge – Ed Pelle, Ph.D. (Estée Lauder Research Laboratories) ____________________________________________________________________________________________ Antioxidants and the Skin – Roger L. McMullen, Ph.D. (Ashland Specialty Ingredients and Fairleigh Dickinson University) ____________________________________________________________________________________________ Development and Agronomic Scale-up of Specialty Crops for Production of Target Molecules – Sheila Dana (Kemin, Des Moines, Iowa)

Poster Competition & Prizes There will be a concurrent poster session.

1st place: $1,500

•

2nd place: $1,000

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3rd place $500

Please send poster abstract submissions by April 15, 2014 to Jenna Jelinski at JJelinski@morretec.com.

Registration EARLY REGISTRATION – PRIOR TO May 15, 2014 Members Non-Members Students/Unemployed Early registration: $75 $125 $0 Late registration: $150 $200 $100 For registration, visit www.nyscc.org.

Hotel Accomodation Club Quarters, World Trade Center 140 Washington Street, New York, NY 10006 Arrival: June 4th • Departure: June 5th or 6th Club Standard Superior

June 4th – $271 June 4th – $291 June 4th – $311

June 5th – $236 June 5th – $256 June 5th – $276

All rates are exclusive of tax and based on single occupancy. There is a charge of $15 for each additional person, age 12 and over.

Individuals can call or e-mail directly to our Member Services Department to make room reservations.

Member Services can be reached at (203) 905-2100 from Monday – Friday, 7:00 a.m.–11:00 p.m. and Saturday, 10:00 a.m.–6:00 p.m. (EST); or via e-mail at memberservices@clubquarters.com.

Please mention that you will be attending the NYSCC Antioxidant Symposium at the New York Academy of Sciences.

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2014 TRI-Princeton Events Human Hair/Cosmetic Interactions • May 15-16 Processing Services for dry powders Jet Mill Technology for Ultra Fine Bases, Face Powders, and Pigments. FDA cGMP

The Jet Pulverizer Co. ®

800.670-9695 www.jetpulverizer.com info@jetpul.com

sensiva® – multifunctional additives designed for your innovation euxyl® – optimum preservation according to your needs

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1 1-888-267-4220 -888-267-4220

This two-day professional education course is based on the premise that an understanding of how cosmetic treatments affect human hair properties is critical for the development of successful products. The instructors approach the material from a fundamental perspective; offering students the opportunity to closely examine the basic structure of hair and hair care products as well as interactions between the two. Lecturers include: Trefor Evans, Jim Anderson, Bob Lochhead, Roger L. McMullen, Crystal Porter, and Randy Wickett.

Hair & Scalp Biology Workshop • September 15 This one-day intensive workshop on hair and scalp biology, taught by leading hair biologist, Dr. Gillian Westgate, is intended to organize and advance hair and scalp biology as an integral component of hair care product development.

Science Behind Hair Claims • September 16-17 This course focuses on attributes of hair, together with testing and technical knowledge, leading to the support of product claims. In addition, we will review the media perspective and regulatory aspects of the claims process.

Applied Hair Science Conference • September 18-19 This conference brings together people creating hair care products, today and tomorrow, with the creators of the newest product technology, technical insights, and measurement methods. TRI-Princeton requests abstract submissions on hair science and its applications for podium and poster presentations. We invite all topics related to hair science. Topics…

Fiber science • Biology and ethnic variations • Chemistry and proteomics New measurement techniques • Developing technologies and approaches Abstracts for podium presentations must be submitted by March 31, 2014. Interested applicants should e-mail their abstracts to the Conference Organizer at events@triprinceton.org.

For more information on all these events contact Eleanor Lehman at events@triprinceton.org; or call (609) 430-4820; or visit the website at www.triprinceton.org/education.

Plant Science Seminar • April 23rd Seasons • Washington Township, NJ 4:30 p.m. Educational Hour: Dr. John Greaves Phytochemical Variation and Hyper Accumulation—Not All Plants Are Created Equal 5:30 p.m. Dinner 6:30 p.m. Dinner Speaker: Dr. Nayak Satish How Mother Nature Protects n Pricing • Member preregistered – $35 • Member at the door – $75 • Non-Member preregistered – $70 • Non-member at the door – $110 • Students – $10 ($50 at the door) • Emeritus – Free ($40 at the door) • $40 fee across the board for at the door registration.

Registration online at www.nyscc.org.

Registration questions: John Carola at johnc@protameen.com.

Seasons • 644 Pascack Road, Washington Twp, NJ 07676 (201) 664-6141 28

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Employment Opportunities Send employment ads to…Jason O’Neill (Jason.Oneill@kemin.com).

Employment listings published in the Cosmetiscope are abridged due to space limitations. n R&D CHEMIST EnglewoodLab, the new standard for innovation and contract manufacturing, has an opening for a Senior R&D Chemist. This position is located in Englewood, NJ. Responsibilities: • Formulation of all types of Skin Care and Sun Care products including but not limited to creams, lotions, serums, and other innovation upscale skin care solutions.

• Knowledge of cosmetic/personal care raw materials, functionality, and interactions.

• Understanding of emulsion and surfactant technology as well as general formulation techniques.

• Must be able to perform and monitor product stability.

• Must be a team player, but able to work independently.

Qualifications: • B.S. in Chemistry, Biology, or related field.

• 5+ years R&D bench experience formulating skin care products.

• Knowledge of industry trends.

• Able to work in a fast pace environment.

• Creative thinking, technical writing, and organizational skills.

• Knowledge of Microsoft Suite.

To apply, please contact Ni’Kita Wilson at: niki@englewoodlab.com, or David Chung at: dep@englewoodlab.com. No Phone Calls Please! ________________________________________________________________

n SKINCARE PRODUCT ENGINEER Rodan + Fields is seeking a Product Engineer to join its Product Development team. We are seeking a scientist with a strong technical understanding of our product category to play a pivotal role in the development and manufacturing of the company’s domestic and international skincare and OTC products. The Product Engineer will be responsible for moving product prototypes from the formulation stage, through scale-up, into full-scale manufacturing, and through product life-cycle manufacturing.

Responsibilities will also include process improvements, implementation of formulation changes, CMO technical management and, with the quality group, implementation of corrective actions. The Product Engineer will report to the Director of Product Development.

Responsibilities: • Work with Product Development team, outside labs, and/or CMOs to assist in the development of formulations that meet all product aesthetics, quality, safety, costs, benchmarking, and performance criteria from the perspective of manufacturing feasibility.

• Manage critical relationships with external formulation labs, contract manufacturers, fragrance houses, and R&D partners.

• In partnership with the regulatory group ensure all products are compliant with relevant U.S. and international regulations.

• Work with Operations/Quality functions to scale-up, validate, and commercialize all new product introductions including formulation modifications and improvements.

• Provide technical innovation to formulations including ingredients and delivery systems.

• Proactively research new concepts, materials, technical opportunities,

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and partnerships for products and manufacturing.

Requirements: • 7+ years of skincare product development and manufacturing experience; hair care product experience a plus.

• Experience in skincare and OTC product categories.

• Bachelor’s degree (Master’s degree preferred) in Chemistry or related science.

• Experience in dealing with multiple CMOs that specialize in dermatological product development and manufacturing. Knowledge of the best in class CMO facilities to optimize the product development lifecycle.

• Experience and knowledge to anticipate various technical and regulatory hurdles in developing these products for global registration and commercialization.

• In-depth understanding of the issues and controls for the scale-up of these products for both pilot and commercial scale.

• Sound understanding of the basic principles of good experimental design, data analysis, and interpretation.

• Strong interpersonal, communication, and teamwork skills.

• Good time management and ability to work under pressure.

• Outstanding written and verbal communication skills.

• Advanced level knowledge of the Microsoft Office Suite and IT systems.

Please send resume to: jclausen@rodanandfields.com. ________________________________________________________________

n R&D CHEMIST – COLOR COSMETICS Dermaceutical Laboratories, a customhouse contract manufacture in Teterboro, NJ, is seeking a senior R&D Chemist to join our team.

Responsibilities: • Develop and formulate all color cosmetics related products including lipsticks, powders, foundations, eye shadows, etc.

• Prepare and conduct stability and compatibility testing.

• Manage a team of technicians.

• Interact with Manufacturing, Marketing, Purchasing, and Quality departments.

• Oversee production batches when necessary.

Qualifications: • Degree in Chemisty or related science.

• 5+ years experience in the personal care/cosmetics industry.

• Excellent communication and organizational skills.

• Must be able to work independently and have solid managerial skills to lead a team.

• Knowledge of industry trends.

If interested, please submit resume to: wchang@dlabllc.com. ________________________________________________________________ n ASSOCIATE SCIENTIST Kobo Products, Inc., a raw material cosmetic/personal care manufacturer and distributor, is seeking an experienced Scientist for Technical Service.

Job responsibilities: • Provide technical support to the sales team and customers.

• Complete forms and questionnaires.

• Prepare and maintain MSDSs and other technical documents.

• Inspect the documents of raw materials and distributed products.

• Release new products.

• Run lab experiments on assignment on limited basis.

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Employment Opportunities Requirements: • 2-4 years experience supporting technical service in the cosmetic or personal care industry.

• Knowledge of global regulations required.

• REACH EU regulation experience preferred.

• Bachelor’s degree required; Chemistry major preferred.

• Person must able to multitask in a fast pace environment and possess strong communication skills.

• Microsoft Office experience required (Word, Excel, Powerpoint, and Outlook).

Please send resume and include salary requirements to: stortorella@koboproductsinc.com.

Reference “Associate Scientist” in the subject field. ________________________________________________________________

n TECHNICAL SALES REPRESENTATIVE Biosil Technologies, Inc., a global supplier of specialty ingredients in the personal care market, is seeking a Technical Sales Representative. The territory will cover the North Eastern U.S. and parts of the Midwest. The position will require more than 50% travel and will report to our office in Allendale, NJ when not traveling.

General responsibilities include: • Developing and maintaining relationships with new and existing customers.

• Visiting R&D centers, product developers, purchasing, and formulators.

• Identifying customer needs and initiating new projects.

• Creating marketing material.

• Participating in industry trade shows.

Requirements: • B.S. in Chemistry or related science.

• Strong interpersonal and communication skills.

• Proficiency with Microsoft Office.

• Sales experience a plus.

Please send resume and salary requirements to: philip@biosiltech.com. ________________________________________________________________

n TECHNICAL MARKETING SUPPORT Gattefossé USA, located in Paramus, NJ, is seeking a Technical Marketing Support Leader. This position will support the marketing activities of the company, with a particular focus on internal tools and training.

Job responsibilities: • Provide technical/marketing support and customized training to sales team and distribution network in North America.

• Ensure implementation of tools and training modules for sales team and distributors.

• Coordinate development, creation, implementation, and delivery of staff training programs and sales tools.

• Provide local sales and marketing support including customer visits, seminars, lab sessions, and presentations.

• Relay market information to corporate marketing team.

• Contribute to execution of marketing plan, including creation and maintenance of newsletters, webinars, presentations, etc.

Qualifications: • Bachelor’s or Master’s Degree in a scientific field, with an interest in cosmetic chemistry.

• Strong computer skills; must be proficient in Microsoft Office. Knowledge of Adobe Creative Suite is a plus.

• Must have excellent communication skills.

• Formulating experience and/or marketing background is a plus.

Please e-mail cover letter and resume, including salary requirements to: careers@gattefossecorp.com.

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n STAFF SCIENTIST – FEMININE CARE Playtex/Energizer Personal Care, located in Allendale, NJ, is seeking a Staff Scientist to work in Feminine Care. The primary focus for the Staff Scientist will be the development, management, and translation of unique and advantaged technical innovation for application in Feminine Care products. This position will assist the Manager in the development and implementation of unique and advantaged technologies to support the product roadmap. A B.S. in Biomedical, Mechanical, or Chemical Engineering preferred and a minimum of 8-10 years of experience in a related consumer goods category is preferred. Demonstrated ability to lead technical innovation with a history of success with respect to innovation and successful market introductions is mandatory.

Apply online: http://www.energizerholdings.com/en/careers/external/Pages/index.aspx. ________________________________________________________________

n ASSOCIATE SENSORY SCIENTIST Schick/Energizer Personal Care, located in Milford, CT, is seeking an Associate Sensory Scientist. The successful candidate will execute, analyze, and report research results from sensory testing to ensure product development and innovation project objectives are met.

A B.A./B.S. and 1-2 years of experience in a corporate CPG sensory science environment are preferred.

Apply online: http://www.energizerholdings.com/en/careers/external/Pages/index.aspx. ________________________________________________________________ n STAFF PRODUCT RESEARCHER – CONSUMER SCIENCE Playtex/Energizer Personal Care, located in Allendale, NJ, is seeking a Staff Product Researcher to work in its Consumer Science department. The successful candidate will manage all phases of consumer and sensory research programs in support of Product Development initiatives. He/she will independently develop, implement, and administer a broad spectrum of consumer guidance and sensory projects. In addition, he/she should possess and promote a passion for integrating a consumer perspective into the Product Development process. A B.A./B.S. in Science/Engineering or Behavioral sciences (Psychology, Marketing Research) with 10+ years of relevant experience with consumer product testing within the consumer goods industry is required. Understanding of the new product development lifecycle is desirable. An advanced degree and knowledge of market research beyond product testing in R&D are excellent assets for this job.

Apply online: http://www.energizerholdings.com/en/careers/external/Pages/index.aspx. ________________________________________________________________

n APPLICATIONS LAB CHEMIST Kobo Products, Inc., a raw material cosmetic/personal care manufacturer and distributor, is seeking an experienced Applications Lab Chemist. The preferred candidate should have strong communication skills, and at least 3-5 years formulation experience in color cosmetics.

Job responsibilities: • Formulate a wide variety of new cosmetic formulas.

• Ability to troubleshoot formulas.

• Develop and make presentations.

• Attend trade shows to support sales with customer discussions.

• Flexibility to attend seminars and conferences, if requested.

• Ability to work with customers in Kobo’s labs to create new finished products with them.

Requirements: • 3-5 years industry experience on the bench formulating cosmetics (i.e., emulsions, anhydrous systems, powders, and sunscreens).

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• Knowledge of cosmetic/personal care raw materials (i.e., functionality, interactions, and regulatory limits).

• Strong problem solving and communication skills (oral and written).

• Flexibility to travel domestically and internationally.

• Must be able to multi-task in a fast-paced environment.

• Microsoft Office experience required (Word, Excel, Powerpoint, and Outlook).

• Self-motivated.

• B.S. degree in related field preferred.

Please send resume and include salary requirements to: stortorella@koboproductsinc.com.

Please reference “Applications Lab Chemist” in the subject field. ________________________________________________________________

n RESEARCH DIRECTOR IFF, located in Union Beach, NJ, has an immediate opening for a Research Director who will lead the identification, research, and development of delivery technologies that provide IFF with new opportunities for profitable growth. This position will support the strategic mission of the Delivery and Material Technology Team via planning and execution of complex technical work under general direction of management. This will involve identifying, developing, and prototyping delivery technologies based on a critical assessment of the patent and scientific literature, identified customer and consumer needs, and opportunities for competitive advantage.

Accountabilities: • Innovation: Identify emerging trends and opportunities for truly differentiating product technologies and integrate into research program.

Collaborate in development and execution of intellectual property strategy to ensure long-term strategic advantage.

• External Perspective: Establish and lead relationships with academic and industry partners that expand technical capabilities leading to breakthrough technologies.

• Program Leadership: Develop technical approaches, create novel methods and prototypes as well as formulate and execute sound technology validation plans.

• This position will require an expert-level understanding of encapsulation and other delivery systems, material science, and related manufacturing processes. The ideal candidate for this position should be able to demonstrate skills to justify eventual promotion to positions of significantly greater responsibility within the organization.

Essential: • Ph.D. in Chemistry, Food Science, Chemical Engineering, or other appropriate discipline.

• 10-15 years of industrial and/or post-doctoral research experience.

• Demonstrated ability to conduct original and independent research as evidenced by patents, publications, etc.

• Expert-level understanding of delivery systems.

Preferred: • Evidence of significant involvement in new technology development and commercialization.

• Strong track record of leading the development of new technologies from concept to commercialization.

For more information, go to: www.iff.com/careers. Reference ID is 1702-292. ________________________________________________________________ n APPLICATIONS CHEMIST Sensient, located in South Plainfield, NJ, is seeking an Applications Chemist.

Position summary: • Prepare personal care products following existing formulations under direction of Manager and Senior Chemist. Maintain and manage inventories

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of existing prototypes for customers, sales kits, and trade shows. Participate in new product development on as needed basis. Conduct all appropriate testing, including stability, and order raw materials and lab supplies.

Essential functions: • Must handle multiple projects.

• Prepare prototype formulations.

• Maintain prototype formulations stock.

• Maintain accurate laboratory records.

• Assist in new product development.

• Color matching and evaluation of samples and raw materials.

• Interface with Technical Services and Quality Control.

• Maintain supplies and equipment necessary to develop, package, and distribute prototype samples in response to Sales needs.

• Abide by company policies/procedures.

Education:.Bachelor’s degree in Chemistry or related science preferred.

Experience: One to two years of applications formulation in color cosmetics is preferred. Must be proficient in Microsoft Office.

Interested candidates should send resumes with salary expectations to: Nada Vansaghi at: nada.vansaghi@sensient.com.

Please use subject line: Applications Chemist-NJ. ________________________________________________________________ n FORMULATION CHEMIST (DAYTON, NJ) Salvona Technologies, a technology company specializing in advanced controlled release systems in nanotechnology and microencapsulation for topical (skin) applications, is seeking a Formulation Chemist in its Dayton, NJ facility.

Duties: • Develop practical final formulations for the personal care and dermatology markets.

• Conduct skin/scalp/hair tests to affirm product efficacy.

• Qualify products and evaluate product stability.

Practical knowledge required: • 1-3 years of formulation experience.

• Practical experience in the field of cosmetic, personal care, dermatology, or household product development is preferred.

• Knowledge of topical skin care formulation ingredients, procedures, and esthetics (Cosmetic/Dermatological preferred).

General Qualifications: • Bachelor’s degree in Chemistry or equivalent experience.

• Ability to communicate effectively with teams and prospects.

• Demonstrated ability to focus on achieving commercial goals.

• Proven ability to work independently, be motivated, and be self- disciplined.

• Familiar with Excel and able to compute and interpret basic statistical analysis (Student’s t test).

• Familiar with Powerpoint and able to present technical project reviews.

• Able to handle multiple tasks under stressful conditions.

• Excellent verbal communication and computer skills.

• Hands-on person.

How to Apply: Visit http://salvona.wufoo.com/forms/salvona-job-application/.

At this time, our company is not offering to sponsor visa candidates. ________________________________________________________________ n REGULATORY AFFAIRS SPECIALIST Playtex, a division of Energizer Personal Care located in Allendale, NJ, is a leading manufacturer and distributor of consumer and personal care products. The Regulatory Affairs Specialist provides regulatory guidance and support to the successful commercialization of all personal care product categories, with emphasis on cosmetics and OTC drugs. A Bachelor’s (Continued on page 32)

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Employment Opportunities degree in Biology or Chemistry and 4-6 years related regulatory experience is required. Must have thorough knowledge of FDA regulations and experience with cosmetic, drug, and/or device product registration.

Apply online: http://www.energizerholdings.com/en/careers/external/Pages/index.aspx ________________________________________________________________ Hayward Laboratories Subs, ET Browne Drug Co. Inc. has several professional positions open. We are located in East Stroudsburg, PA, minutes from Northwest NJ, located right over RT 80 in the Delaware Water Gap area.

n 1.QA LAB MANAGER Responsibilities: • Manage all testing requirements for raw materials and finished goods.

• Assure that company meets all regulations including GMP and GLP in accordance with FDA and European ISO standards.

• Manage supplier approval programs.

Requirements: • Minimum B.S. degree in applied science, and 5 years experience in OTC/Cosmetic environment.

• Familiarity with advanced analytical instrumentation is a plus, and must have good computer skills.

• Must be a leader, team player, and self-starter. n 2. INTERNATIONAL REGULATORY AFFAIRS MANAGER Responsibilities: • Assure product and ingredient regulatory compliance to support export markets.

• Correspond with regulatory bodies and foreign subsidiaries as needed.

• Assess regulatory trends and developments in cosmetic and personal care products.

• Interact with Marketing, Sales, and Product Development regarding EU, ASEAN, NICNAS, ANVESA, etc.

Requirements: • Minimum B.S. degree in an applied science.

• Minimum 5 years regulatory compliance experience in cosmetics and personal care.

n 3. ANALYTICAL CHEMIST, INSTRUMENTATION SPECIALIST Responsibilities: • Must be able to operate and maintain HPLC, GC, FTIR, and UV-VIS instrumentation.

• Must be familiar with sunscreen, preservative, and other method development, calibration, validation, and transfer.

• Responsible for supporting other activities of the QC laboratory.

Requirements: • B.S. degree in Chemistry or related field.

• 3+ years experience in an OTC/Cosmetic environment, and USP procedures.

Please forward your resume and salary requirements to: wneumann@etbrowne.com. ________________________________________________________________

n SCIENTIST Rodan + Fields, LLC is seeking a scientist with technical understanding of skin care and OTC product categories to play a pivotal role in the development and manufacturing of the company’s domestic and international skin care and OTC products. 7+ years of skincare product development and manufacturing experience and a Bachelor’s degree in Chemistry or related field is required. Responsibilities include moving product prototypes from the formulation stage, through scale-up, into full-scale manufacturing and through product life-cycle manufacturing. Responsibilities also include 32

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process improvements, implementation of formulation changes, CMO technical management, and, with the quality group, implementation of corrective actions.

Please send resume to: jclausen@rodanandfields.com. ________________________________________________________________

n SALES REPRESENTATIVE: COSMETIC SPECIALTIES NORTHEAST Independent Chemical Corporation.

Job description: The Technical Sales Representative will promote the sales of Independent Chemical’s Cosmetic Specialty and Commodity Products in his/her territory and, in certain cases, also develop the business at Regional or Global Key Accounts, traveling up to 70% of the time. This position reports to our Glendale, NY home office but will be home- based, and the candidate must live within the territory. The territory consists of the Northeast United States beginning in Northern NJ and north to Eastern Canada. The sales target for the territory is approximately $5 million.

Major responsibilities: • Develop new applications for Specialty Products while growing Commodity Products; optimize selling prices taking into account profit volume opportunities on commodities across our product lines.

• Set pricing for commodities to meet company targets.

• Develop contacts with customers at all levels in the commercial and technical departments to strengthen their business relationship with Independent Chemical.

• Regularly monitor the financial situation of his/her customers and make sure that their payments to Independent are on time.

• Plan all customer visits through the establishment of clear objectives and action plans.

• Produce and keep updated a Market Data Base of the territory where all the relevant information on customers, volumes, and prices of the commodities used, their application, and the competitors positioning is available.

• Independently set commodity pricing in cooperation with supplier pricing to meet profit targets. Choose which products to offer for specific markets.

• Weekly reporting on the major accomplishments and challenges in his/her territory.

• Work in close cooperation with Customer Support Representatives and Sourcing Group for new materials.

• Have strong technical knowledge of specialties and commodities in different cosmetic applications and keep this knowledge updated.

Desired skills and experience: • Bachelor’s degree in Chemistry, Chemical Engineering, or related field.

• 3+ years in a cosmetics formulation lab—skin, hair, or color.

• 2-5 years of sales experience in service and technology based industries.

• Cosmetics specialty chemical sales experience is preferred.

• Demonstrated experience in solving commercial and technical problems with customers.

• Strong interpersonal/sales background coupled with an understanding of the sales process and selling excellence methods.

Respond to: Jonathan@Independentchemical.com.

More info: www.Independentchemical.com.

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