Page 1

CSA’19 CSA’19

PRESENTATIONS

PARTNERS


CORK IN SCIENCE AND APPLICATIONS 2019

22nd May

Cork: NEW USES IN ARCHITECTURE


•  “Today in addition to the awareness of the limitation of planet reserves, also begins to exist awareness of environmental costs that industrial development has caused on the planet associated with the awareness that the construction is a major source of pollution of the planet" buildings are major contributors indecomposable of toxic waste in the world. •  The construction industry uses three billion tons of natural materials on the planet per year Font: Sam Martin, The right stuff, in Mother Earth News, June/July 2000

Planet Natural Resources Awareness


Buoyant

Compressible

Light

Elastic

Poisson's ratio 0

Poisson's ratio is the ratio of the relative contraction strain (or transverse strain) normal to the applied load - to the relative extension strain (or axial strain) in the direction of the applied load Impermeable: - liquids - gases

Insulation: - thermo - acoustic

Resistance: - friction - rot

Slow : - combustion - time

Cork has unique properties that no other product natural or artificial can supersede

CORK :

a

Cork unique natural properties

material


Font: http://www.flickr.com/photos

Use of Cork Through history - architecture Convent of the Capuchos, 1560


Font: Santos,O. Clausters Unidos pela Natureza o mundo do vinho e da Cortiรงa, Amorim, 2008

Use of Cork Through history - architecture Buรงaco Palace was part of a Discalced Carmelite convent , 1628


Arrábida monastery, Setúbal, 1542

http://aladesetubal1.blogspot.ca/2011/10/passeio-ao-convento-daarrabida.html

streets of Monsaraz. XVII-XVIII

http://cebolasdocampinho.blogspot.ca/2013/09/porta-decurtica.html

Use of Cork Through history - architecture


Partition Wallls, Doors, Windows

streets of Monsaraz. XVII-XVIII

http://cebolasdocampinho.blogspot.ca/2013/09/porta-decurtica.html

Use of Cork Through history - architecture


streets of Monsaraz. XVII-XVIII

http://cebolasdocampinho.blogspot.ca/2013/09/porta-decurtica.html

ROOFS

Exterior Walls – Cortiçadas

Use of Cork Through history - architecture


Use of Cork Through history - architecture Chalet of the Countess of Edla, King Ferdinand II, 1870


Use of Cork Through history - architecture Proust cork-lined bedroom, (1871 –1922)


Use of Cork Through history - architecture Tudor House, West Sussex, UK, (18~ )


Cork Today - cork composites Cork and design


Font: http://radardecoracao.com.br/02/corque-design-apresenta-pecas-de-cortica-aos-cariocas/

Cork Today - design Ana Mestre and others


Font: industrie Amorim (2012)

Cork Today - Architecture Thermal, acoustic insulation


Font: industrie Amorim (2012)

Cork Today - Architecture finishing cork flooring


Font: i http://www.grupoamericoamorim.com/xms/files/2011/Arte_Cortica.pdf

Cork Today - Architecture Sagrada Familia Barcelona, Cripta - Jordi Bonet i Armengol


Font: i http://www.grupoamericoamorim.com/xms/files/2011/Arte_Cortica.pdf

Cork Today - Architecture Nezu Museum , Kengo Kuma and Associates


Font: http://cultour.com.pt/tours/coimbra

It is a pre-fabricated and disassemble Pavilion that was later rebuilt in Coimbra. Is formed from a metallic structure, over which walls have been built and covered with around 55 tons of expanded cork agglomerate and also by hand made glazed tiles on the welcome patio. The choice of cork is related to the fact that it is a 100% natural material, isotherm, extremely versatile and totally recyclable and of which Portugal is the main source of production.

Cork Today - Architecture Souto Moura e Siza Vieira, Expo 2000 Hannover Portugal pavilion


Font http://www.archdaily.com/136301/logowines-winery-pmc-arquitectos/

The rhythm given to the facades, with a strong definition of horizontal lines, using various thicknesses of cladding panels of cork, where they fuse the openings for natural lighting inside is reinforced by the natural behavior of the chosen material, causing a set of textures, shades and shadows that mutates over time, in a clear allusion to the maturation of the wine during the period of production.

Cork and the Future - Architecture Logowines Winery / PMC Arquitectos in Évora Pt, 2007


Font:http://www.d10photo.com/davidpereira/portfolio/eco-cabana-barbini-arquitectos-cascais

/

There are endless creativity options which are being explored by new generation designers who are a lot more environment conscious. "The use of biodegradable, ecological and recyclable material such as cork is increasing, especially in the area of product design," he says. In Portugal we regard cork as an iconic material. It has an age-old reputation that dates back to 3,000BC," he says.

Cork and the Future - Architecture ECO-CABANAS, Barbini Arquitectos, Cascais, Pt, 2008


Font: http://barrelsecrets.wordpress.com/tag/alvaro-siza-vieira/

The new cellars of Quinta do Portal were built within an already built complex, a unit that dominates and is dominated by the landscape (of vineyards). There is no doubt that in the essential and whenever active, agriculture moulds the landscape. This is the first reason for the beauty of the Douro. It is by nature, a disciplined building. The functional needs, as well as the space, humidity and temperature needs determine its expression.

Cork and the Future - Architecture Quinta do Portal, Alvaro Siza Vieira , Sabrosa, Pt, 2008


Font:http://www.promocork.com/files/cortica-arquitetura.pdf

The first contact with the Centre creates admiration. There is no similar building. The whole coating is made with virgin cork (taken the first time) and Amadia (drawn for the third time in cork over 40 years). And for anyone who doubts the quality of material, the architect Manuel Couceiro ensures that "with careful maintenance, cork is for life."

Cork and the Future - Architecture Observatรณrio do Sobreiro e da Cortiรงa, Manuel Couceiro, Couruche, Pt, 2009


Font:http://www.promocork.com/files/cortica-arquitetura.pdf

The Portuguese architect Carlos Couto created a work 2000 m² coated in pure agglomerated cork as a means to reinforce the concepts of innovation and good environmental practices, integrating them to the concept of sustainability.

Cork and the Future - Architecture Expo 2010 Shanghai Portuguese Pavillion, Carlos Couto, Ch 2010


Font:http://www.promocork.com/files/cortica-arquitetura.pdf

Cork And the Future - Architecture Serpentine Gallery, Herzog & De Murron, UK, 2012


JosĂŠ Pedro Sousa, PhDThesis, TU Lisbon

Cork and CAD/CAM technologies , 2009


Font: http://www.shelterbygg.com/

Cork and the Future - Architecture Shelter ByGG, Hugo Amaral, Guimaraes, PT 2012


i cork

This Research is focussed on the use of cork material in architecture. It provides an environment for researchers, architects, designers as well as those in the industry and other interested parties to meet and develop ideas and experiments using cork.

Cork: NEW USES IN ARCHITECTURE


Gain an appreciation and understanding Cork as a material. •  Understanding traditional methods in the use of Cork and learn from that experience. •  Conduct explorations with composite cork materials or products to understand its potentialities and possible applications as a building envelop. • 


Know the industrial cork processing chain and the composite cork products. •  Selection and characterization of cork products and their use changes, i.e. with aging and weathering •  Conduct experiences involving the industry, overcoming potentialities of their materials for future applications on building envelop. • 


Understanding the architectural practice and foreseeing their future needs. •  Selection of new materials and technologies that can, in the future, bring new possibilities of use in architecture and product design. •  Understand how research and industry can work together to develop strategies that can be key to the future applications of cork materials in architecture. • 


UNIVERSITIES / RESEARCHERS

INSTITUTIONS INDUSTRY


2014

1st. Edition_ Natural Materials


2014

1st. Edition_ Natural Materials


2015

2nd. Edition_ Composite Materials


2015

2nd. Edition_ Composite Materials


2014

1st. Edition_ Natural Materials

Use of textile cork and cork stoppers achieve: cork stoppers became a rigid connection

Phase 1

Phase 1/2 MEMBRANE

Material propertie


2015

2nd. Edition_ Composite Materials

Phase 1/2 MEMBRANE

Phase 1

Material propertie


2015

2nd. Edition_ Composite Materials

Phase 1/2 MEMBRANE

Phase 1

Material propertie


2014

1st. Edition_ Natural Materials


2014

1st. Edition_ Natural Materials


2015

2nd. Edition_ Composite Materials

USE OF NATURAL RESINS Problem: to unstable properties mix with cork

Phase 1 CLADDING

Phase 1

LIGHT FILTER Material propertie


2015

2nd. Edition_ Composite Materials

USE OF CNC MACHINE Acoustic characteristics incurve materials using materials in both faces light filter

Phase 1/2 CLADDING


2014

1st. Edition_ Natural Materials

USE OF MDULAR TECHNIQUES in curve surfaces Sound and Thermal characteristics

Phase 1/2 CLADDING


2014

1st. Edition_ Natural Materials

Wall dimensions 3m x 2m

USE OF MDULAR TECHNIQUES

Phase 1 CLADDING

Hexagon dimensions Side: 6.5cm Diameter: 13cm


2014

1st. Edition_ Natural Materials

USE OF MDULAR TECHNIQUES

Phase 1

SELF-SUPPORTING

Phase 1

LIGHT FILTER Material propertie


2015

2nd. Edition_ Composite Materials


2014

1st. Edition_ Natural Materials

UPCYCLE

Phase 1/2

SELF-SUPPORTING


Invited Guest


2015

2nd. Edition_ Composite Materials


2015

2nd. Edition_ Composite Materials


2015

2nd. Edition_ Composite Materials


CORK IN SCIENCE AND APPLICATIONS

Cork’s byproduct used as filter media in a treatment wetland for winery wastewater treatment

Jordi Morató, UPC May 23rd, 2019. 0


Environmental Problem Targeted

Catalunya 39 million of coark oaks Harvest 8.000 ton/year

Most cork unsuitable for cork stoppers 40-70 % sent to landfills 5.000 tonnes year – Catalonia 3


Circular Economy Framework

≈ 60 %

Zero Waste

Save Water

Treatment Wetland

Produce Energy

Gasification pilot plant 4


Ecorkwaste innovative strategy Integrated and sustainable management of cork waste grated and sustainable manageme

generated in the cork industry (LIFE14 ENV/ES/000460)

Diagram of the cork industry

Alternative cork flow– diagram including the ECORKWASTE strategy


Treatment Wetland (TW): Construction, installation, operation and assessment

2 Febrero de 2016

5


Main Objective

Tertiary water treatment to improve the quality of the final winery effluents in the treatment plant located at the Codorniu winery.

CODORNI U

5


Specific Objectives

To minimize landfilling of by-products by means of turning it into value. To demonstrate at pilot scale the feasibility of an innovative hybrid constructed wetland (CW) for the treatment of winery wastewaters, using cork waste as granular media. To reduce water consumption in the winery industry by an onsite wastewater reuse application (water & cork on site circular economy)

6


Analysis of Winery Wastewater

Seasonal variation of temperature, pH, COD and TSS, and Water Flow in CODORNIU WWTP effluent

110 m3/d

Harvesting 250 m3/d

150 m3/d

Data provided by CODORNIU. 7


Analysis of Winery Wastewater

Seasonal variation of Polyphenols, Zn, Ni, Cu and Pesticides in CODORNIU WWTP influent and effluent.

Samples from Nov. 2015 to Oct. 16. 8


Analysis of Winery Wastewater Codorniu WWTP – Low reduction for some Nutrients

8


Pilot Treatment Wetland Tertiary water treatment – Shipping Containers (mobile TW)

Project indicators 200m3

ECORK

year

-Winery Wastewater treated. 95% - Pesticides removal 90% - COD removal 80% - NO3-N removal

9


Pilot Treatment Wetland Open Top Shipping container 20 ft

10


Pilot Treatment Wetland Wetland – Shipping Container 20ft Open Top Waterprofing

11


Pilot Treatment Wetland Control Room – Shipping Container 20ft

12


Pilot Treatment Wetland Control Room – Shipping Container 20ft

ECORK

13


Pilot Treatment Wetland Functional Scheme

Discharge Vertical Flow 2 m3/d Area 14 m2 Irrigation Saturated Intermittent Aeration 27.000 l/d – 4 phases (Air - 25 min each, followed by 35 min w/o) Pump Electrovalve Flowmeter Level and Temp. Sensor

Multiparameter Quality Water Meter

Sedimentation Tank

Wastewater

Inlet Tank

VF

HF

TW Aer.

Outlet Tank

Aerated System 14


Winery Wastewater Treated

Int. Aerated Saturated Vertical TW 665 m3 from Mar-17 until Oct-31 70,000

Treated Water

50,000 40,000 30,000 20,000 10,000

r (2

01

7) Ap r Ma y Ju n Ju l Au g Se p Oc t No v Ja D n ( ec 20 18 ) Fe b Ma r Ap r Ma y Ju n Ju l Au g Se p Oc t

0

Ma

Liters per Mon nth

60,000

2,500 L

500 L

1,000 L

2,000 L

15


28 22:00

20:00

18:00

16:00

1st aeration phase

15 22:00

Environment 20:00

17

18:00

19

16:00

2nd 22:00

20:00

18:00

16:00

14:00

12:00

10:00

8.2

14:00

Temperature TW - July 8ht 08:00

3rd

12:00

3rd 35

06:00

8.1

10:00

4th 8.0

08:00

1st aeration phase

06:00

2nd

04:00

1.0

04:00

2.0

02:00

8.5

02:00

DO TW - July 8ht

00:00

4th

pH

3.0

00:00

30

Temperature(ºC)

22:00

20:00

18:00

16:00

14:00

1.5

14:00

29 12:00

10:00

08:00

06:00

04:00

0.5

12:00

10:00

08:00

06:00

04:00

02:00

DO (mgl-1) 2.5

02:00

31 00:00

0.0

00:00

Temperature(ºC)

Aeration 27.000 l/d – 4 Phases 8.6

pH TW - July 8th

8.4

8.3 4th

3rd

2nd 1st aeration phase

33

31

29

27

25

23

21

Temperature - July 8th TW

16


Increase in Aeration - 27.000 l/d –to 43.000 l/d 8.6

3.5

pH - July

DO - July

3.0

25' aeration phase 40'

25' aeration phase 40' 8.4

2.0

pH

DO (mg l-1)

2.5

1.5

8.2

1.0 0.5

8.0

0.0 6

7

8

9

10

11

12

13

14

15

16

17

18

19

7

8

9

10

11

12

13

14

15

16

17

18

19

Day

Day

Aerated – 4 Phases

31.0 30.5

Temperature (ºC)

6

From July 6th to 15th

30.0

27.000 l/d – 25’ per phase

29.5 29.0

From July 15th to 19th

25' aeration phase 40'

28.5

Temperature - July 28.0 6

7

8

9

10

11

12

13

14

15

16

17

18

19

43.000 l/d – 40’ per phase

Day

17


Pilot Treatment Wetland COD and BOD5 Removal Efficiency First months of operation (new cork) Higher values at the effluent

A

30 20

30 20

Ma y2 2 Jun 19 Jul 25 (17 ) Se p2 8

3 t0 Oc

5 l2 Ju

3 y2

Ma

Ma

p2 Se

) 17 5(

Ju

l2

n1 Ju

17 2(

r7

0 8

0 9

10

y2

A

40

10

Ma

nA

BOD

Oc t 03

40

)

COD (g/m m 2 d)

nA

50

VF_Out

Jul 25

COD

50

Sed_Out

Ma y2 3

VF_Out

Ma r7

Sed_Out

60

BOD ((g/m 2 d)

60

18


Pilot Treatment Wetland NT, NO3-N, NH4-N & N02-N Removal Efficiency 45

40

NT

NT (g/m2 d)

35 30

nA

A

25 20 15 10

15 10

0

40

40

30

nA

A

A

NH4-N

25 20 15 10

30

nA

A

25 20 15 10 5

0

0

Outlet

NO2-N

35

5

Inlet

A

20

0

nA

nA

25

5

NO2-N (g/m2 d)

NH4-N (g/m2 d)

30

5

35

NO3-N

35

NO3-N (g/m2 d)

40

Inlet

Outlet

19


Pilot Treatment Wetland 100

Removal Efficiency %

80 60 40 %

20 COD BOD5

0 -20

TSS

TN

NO3- NO2- NH4- PO43-

TP

Ni

Cu

-40 -60 -80

New cork

Removal Efficiency %

-100

Parameter / No Aerated

- Aerated

21


Molecular Microbiology Analysis Quantitative PCR real time (nirS and nosZ genes, biological markers of denitrification process) and 16S rRNA (general bacteria marker)

Relative abundance of denitrifying genes Relative abundance nosZ/16s 2017 Jan Mar Ap May Jun 0,21 Jul 0,03 Aug 0,03

(%) 2018 0,0005 0,0001 0,0000 0,0004 0,0003 0,0012 0,0000

Rel abund (%) of dry cork nosZ/16s nir/16s 0,0001 0,0049

Relative abundance nir/16s 2017 Jan Mar Ap May Jun 16,29 Jul 0,88 Aug 0,71

(%) 2018 0,003 0,004 0,020 0,033 0,170 0,000 0,001

Chon et al. 2009 ďƒ 0-0.1%

Denitrification scheme

23


Evolution of microbial communities Subsurface cork

No aeration

Aeration

24


Evolution of microbial communities Genes -vs- Sampling site 3 sampling sites on the Constructed Wetland Surface (P1,P3, P6) ďƒ

Kruskal-Wallis Test; p-value: 0,970

Kruskal-Wallis Test; p-value: 0,978

Kruskal-Wallis Test; p-value: 0,776

There are no statistically significant differences between the 3 sampling sites for the data analyzed. 25


Evolution of microbial communities Quantification of GC/g of biofilm in depth cork

26


Evolution of microbial communities Genes -vs- Depth No significant differences for denitrifying genes.

16S

ANOVA; p-value: 0,018

nirS

ANOVA; p-value: 0,904

nosZ

ANOVA; p-value: 0,2

Significant differences for 16s gene) with the lower parts being the least abundant. 27


Evolution of microbial communities

Existing relationship between NT with the molecular results

PRINCIPAL COMPONENT ANALYSIS

nosZ

16S nirS

T-test; p-value: 0,024

MKO; p-value: 0,4 Bartlett; p-value: 0,024

28


Pesticides Removal Inlet and outlet wetland concentrations

20-25% reduction in TW No pesticides on Cork!!

30


Cork Granulates Structure Inner structure of cork granulate in the wetland after 1,5 year of operation

A

B

C

D

Fig. 4 SEM micrographs of wetland cork granulate after 1,5 year of operation ; (A) surface of cork granules in 250 magnifications; (B) surface of cork granules in 1000 magnifications; (C) inner and otter cork granules in 500 magnifications; (D) inner cork granules in 500 magnifications. 32


Conclusions 1. Vertical flow treatment wetland with induced aeration and cork as a filter medium showed a greater removal of NO3-N (81-99%), which suggests that cork could be an alternative material to remove TN (25-90%). 2. Aerated process showed higher removal efficiency for all parameters (TSS, TN, NH4-N, NO2-N, NO3-N, TP, PO4 and Cu). 3. The studied pesticides had not been detected in the cork samples, so the cork treatment wetland has not got over its useful life (1.5 years).

33


CORK IN SCIENCE AND APPLICATIONS

Thank You!!!

Jordi Moratรณ, UPC May 23rd, 2019. 32


Two Cork Houses Emiliano López & Monica Rivera Architects Palafrugell, Girona

STUDY ON CORK APPLICATIONS IN THE CONSTRUCTION SECTOR María Pilar Giraldo PhD Architect pilar.giraldo@incafust.cat


Introduction Cork is an ideal material to meet of the Green Buildings demands due to its properties combined with a favourable ecological footprint.

RENEWABLE RESOURCE

ANTIMICROBIAL

Some by-products BIODEGRADABLE ECO FRIENDLY

NO CHEMICALS / TOXINS EXCEPTIONAL PERFORMANCE


Introduction According to the ranking of FM Cork is a gold material in terms of health above other insulation materials.


Sustainability The environmental impact of its extraction and transformation processes is very low compared to other construction materials.

The cork oak tree sequesters CO2 during its whole life The harvest period is every 9 years (stripping)


Sustainability

The harvesting process is traditionally done by hand, so the only generated carbon is transporting the cork till factory. The transformation processes do not require large consumption of embodied energy.


Sustainability Cork’s extraction and transformation process suppose a carbon footprint much lower than that of other synthetic construction materials with similar thermal properties like polyurethane foam sheets (PU) and expanded polystyrene (EPS).


Material & processes Stoppers

+

Ecological value

-

plastic, petroleum products Compression Moulding

Expanded Cork board Natural cork

+PU Binder Agglomerated Cork

Granules Cork Composites Natural cork Blocks & rolls

Veneers

Floor and coverings

Backing

Cork fabrics Composite panels

+Rubber

Corkrubber

+Thermo plastic

CPC Pellets

Rolls Blocks

Injection Moulding


Material properties Cork has unique properties which give it an unrivalled character. It is light, impermeable to liquids and gases, elastic and compressible, provides thermal and acoustic insulation, it has a certain fire retardant capacity and is highly abrasion-resistant. Furthermore, it is completely biodegradable, renewable and recyclable.


Material properties Cork is combustible but has a certain fire retardant capacity.

Reaction to fire Classification of Cork

E

Which indicates that it is a combustible and flammable material. However, due to its physicochemical properties, the surface forms a carbonized layer that slows down the combustion process. But it does not make it a fireproof material Ongoing research carried out by INCAFUST in collaboration with the Fire Lab of EPSEB - UPC


Material properties The physical properties of cork are due to its cellular structure and its chemical composition. Cork consists of suberin cells in the shape of tiny pentagonal or hexagonal honeycombs, a complex fatty acid and filled with an air-like gas, which makes up 90% of its volume. It possesses an average density of around 200 kg/m3 and low thermal conductivity.


Material properties The chemical composition of cork includes several types of compounds, which are traditionally divided into five groups: • Suberin (45%) - main component of the cell walls, responsible for the elasticity of the cork; • Lignin (27%) - insulating compound; • Polysaccharides (12%) components of the cell walls that help define the texture of the cork; • Tannins (6%) - polyphenolic compounds responsible for the colour; • Wax (6%) - hydrophobic compounds that guarantee the impermeability of the cork. • Ash (4%) - hydrophobic compounds that guarantee the impermeability of the cork.

wax

4%

Ash


Outdoor applications Expanded insulation corkboard for faรงade systems

Corkboard for roof and faรงade claddings

Projected cork for roofs

1B

Vipeq

1A

Ventilated faรงade corktherm.com/

2C

1A Amorim

Projected cork for faรงades

ETICS

1B 2B

Granulated cork for insufflation

Terra.org


Indoor applications

Rolled cork liner Cork ceiling panels

Expanded insulation corkboard for walls and roofs

2A corktherm.com/

1C Acoustic corrector boards

5A

2A

3B

4A Corkcoustic

Cork flooring 1D

composites panels for indoor applications

6B

6A

3C

3A

Anti-vibration and acoustic boards

Amorim

Partition walls


Some applications of cork in construction


MarĂ­a Pilar Giraldo PhD Architect pilar.giraldo@incafust.cat

Thanks for your attention!


Production of Cork hollow pieces by an innovate process based on rotational moulding


O PROBLEMA (The Problem)


Líder (leader)

Empresa Corticeira (Cork Industry)

Parceiros (Partners)

Empresa de Plásticos Instituições de I&D (R&D Organizations)


• Characterization of cork powder and granulates. • Characterization of micronized polyolefins.


•

The introduction of cork softens the thermoplastic.

•

Cork incorporation increases the creep compliance of the composite.


•

Creep recovery depends on the amplitude of the compression force. cork cells crushing Middle range high amplitudes

low amplitude Non-linear behaviour Cell walls buckling linear behaviour


Manuela Mendes

Luís Miranda Sérgio Miranda Andreia C Lopes Sara V Lucas Telma Anágua

A. C. Diogo J. M. Bordado

Isabel Tinoco Abel Rodrigues Miguel Pestana


Instituto Nacional de Investigação Agrária e Veterinária, I.P. Av. da República, Quinta do Marquês, 2780-157 Oeiras, Portugal Tel : (+ 351) 21 440 3500 | Fax : (+ 351) 21 440 3666 www.iniav.pt


Pyrolysed cork wastes used for ultra-light-weight microwave absorbers, EMI shielding or RAM materials Robert C. Pullar a

rpullar@ua.pt

Rui M. Novais a, Ana A. P. Caetano a, K. A. Krishnakumar and Kuzhichalil P. Surendran b a

b

Dept. Eng. Materials and Ceramics/CICECO – Aveiro Materials Institute, University of Aveiro, Aveiro, Portugal

Materials Science and Technology Division, CSIR-NIIST, Industrial Estate, Trivandrum 695019, India

b


Microwave absorbers – 0.3-300 GHz ď Ž

There is a great deal of interest in microwave (MW) absorbing materials, for EMI shielding and military/ stealth technology as radar absorbing materials (RAM) at GHz frequencies Stealth aircraft, ships & vehicles with RAM material incorporated Blocking of radar & military comms EMI shielding for testing, standards, security & health applications


The X-Band (8-12 GHz) of Great Interest ď Ž

X-band (wavelength ~2.5-3.7 cm) is used for military radar and communications, some commercial and civil wireless and satellite communications, motion sensors and speed detection


Carbon (graphite) is a well known GHz / MW Absorbing Material 

Has been used as powder (carbon black, charcoal), carbon fibre, carbon nanotubes (CNTs) and graphene

Carbon powder used in commercial absorbing materials, usually in composites with densities of ≥ 1 g cm-3

PMMA composite with 7 wt% CNTs added, d = 1.2 g cm-3

Pande et al, DOI 10.1007/s11671-008-9246-x

Carbon fibre/CNT/Ni powder composites, d = ~0.9 g cm-3

Liu et al, DOI 10.1016/j.carbon.2013.11.027


Specific Shielding Effectiveness, SSE 

Most papers talk of Shielding Effectiveness, SE, in dB – a value greater than -30 dB is generally considered to be very good

However, another useful value is Specific Shielding Effectiveness, SSE, in dB g-1 cm3, considering the density

This is very important if lightweight materials are required, e.g. stealth coatings for aircraft or vehicles, or portable equipment Cork would seem an obvious choice of material Made of 20 mm wide hexagonal cells, a very light material, d = ~0.24 g cm-3 Can be pyrolysed to form carbon BUT LITTLE WORK ON CORK


Cork is the Bark of a Slow Growing Oak (Quercus Suber Suber)) from the Mediterranean

50% of all cork comes from Portugal

Bark is harvested every 9-13 years, but tree lives on unharmed as carbon sink for >200 years


Cork is a Renewable Resource, with a Natural 33-DOM Microstructure Wine Corks

a) Hexagonal Radial section b) Rectangular Tangential or Axial section

~50,000 t per year of waste cork powder & granules are generated by the cork industry – currently most is burnt to generate energy


We Valorise Waste Cork Products ď Ž

Powder called MF5, made by Amorim in Portugal, as well as waste cork discs, winestoppers, granules and other wastes

ď Ž

MF5 = 300300-500 mm particles, but bulk density much less than cork wood, at 0.050.05-0.07 g cm-3


We also used samples of Solid Cork from Recycled Cork Wine Stoppers ď Ž

Before pyrolysis, d ~0.16 g cm-3, lower than 0.24 of fresh bark

ď Ž

Solid cork expands during pyrolysis. Afterwards, volume = 134 %, weight = 28 %, d ~0.034 g cm-3, similar to the powder

We also pyrolysed cork sheets


Pyrolysed Cork  Biomimetic Carbon 

Graphite furnace at 900 ºC in Ar or N2 cork  carbon

The pyrolysed cork loses >70% weight, but maintains the same cellular microstructure as the original cork, but thinner walls

>70wt% loss

In the pyrolysed cork, structure still like cork, but made of pure carbon, and is nanoporous

Pyrolysed at 900 ºC

Wood

Carbon

This means it is much lighter – d now 0.031 g cm-3, 1/8 of cork wood, & ½ that of the MF5 cork waste powder


TGA/DSC of Cork Pyrolysis in N2

Water loss below 100 ºC, then volatile organics at 200-250 ºC, and suberin, etc., at 550-600 ºC – no further weight loss Even in air, cork can withstand >500 ºC before losing structure


SEM Images of Pyrolysed Waste Cork Powder (pure carbon, d = 0.03 g cm-3)


Shielding Measurements in the XX-Band • The studies were done in a vector network analyser using the wave guide method. SER, SEA and SET (= R+A, Reflection + Absorption) were calculated • Solid Cork samples were made into a rectangular shape of 10.1 x 22.86 mm, with varying thickness, through grinding using sand-coated polishing paper. Samples with thicknesses of 3, 5, 7 and 8.6 mm were prepared • Cork Powder samples were suspended in paraffin wax in the ratio (powder to wax) of 1:4 by mass. The composite was then hot pressed to form 10.1 x 22.86 mm rectangles • SSE (Specific Shielding Effectiveness) calculated from density • For comparison, we also measured un-pyrolysed cork samples


MW Measurements of Un-Pyrolysed Cork We did not expect the unpyrolysed cork to be very good, and indeed this proved to be the case All had very poor SE throughout the X-band

Cork powder Thickness(mm) 1.78

SER (dB) 0.1-1.2

SEA (dB) 0.01-0.3

SET (dB) 0.2-1.3

Finely powdered cork (>100 mm) Thickness(mm) SER (dB) 1.60 0.1-1.1

SEA (dB) 0.01-0.2

SET (dB) 0.1-1.2

Solid cork A Thickness(mm) 5.7

SER (dB) 0.1-0.8

SEA (dB) 0.01-0.4

SET (dB) 0.1-1.1

Solid cork B Thickness(mm) 5.9

SER (dB) 0.1-0.8

SEA (dB) 0.01-0.4

SET (dB) 0.1-1.1

Flat cork sheet Thickness(mm) 5.75

SER (dB) 0.1-0.2

SEA (dB) 0.2-0.3

SET (dB) 0.3-0.6

Partially combusted cork Thickness(mm) SER (dB) 8.05 0.01-0.7

SEA (dB) 0.01-0.2

SET (dB) 0.01-0.8


X-Band MW Measurements of Pyrolysed Cork Powder in Wax Composite • The pyrolysed cork waste powder is VERY fine and light, and had to be mixed in a composite to be handled and measured Thickness(mm) 1.65

SER (dB) 3.0-7.9

SEA (dB) 8.9-11.6

SET (dB) 14.4-18.1

Density of the wax composite is 0.946 g cm-3 Not very high SE values, but this composite is only 20% pyrolysed cork – the rest is wax In all these samples, SER contributes much less than SEA to the total SET


X-Band MW Measurements of Pyrolysed Solid Cork of Various Thicknesses Thickness(mm) 2.96 4.98 6.95 8.6

SER (dB) 3.7-8.7 3.8-8.5 3.8-7.4 3.9-7.6

SEA (dB) 12.3-17.7 14.1-18.5 22.9-27.7 27.5-34.0

SET (dB) 19.8-23.3 20.4-24.5 28.5-32.7 34.0-38.3

Values increase with thickness, to over -30 dB for 7 & 8.6 mm Not surprisingly, we can see that it is the absorption SEA which increases with thickness The reflectance SER remains constant, as the surface microstructure is constant


What is REALLY Exciting is the SSE Thickness (mm)

SSE (dB g-1 cm3)

Pyrolysed Solid Cork

2.96 4.98 6.95 8.6

SET (dB) 19.8-23.3

20.4-24.5 28.5-32.7 34.0-38.3

Density (g cm-3) 0.031

SSE (dB g-1 cm3) 638.7-751.6 658.0-790.3 919.4-1054.8 1096.8-1235.5

As pyrolysed cork is so light (0.03 g cm-3), SSE is VERY HIGH 1200 dB g-1 cm3 is the highest reported SSE These are solid pyrolysed cork, so no polymer binder or composite to increase density of material Sustainable material!


Cork structure enhances MW absorption due to internal reflection within the cells


How does this compare to Carbon Foams Using GRAFOAM® FPA-20 and GRAFOAM® FPA 10, 1-4 mm high Foam densities = 0.324 & 0.166 g cm-3, cells are 100’s of mm 1 & 4mm = GRAFOAM FPA-20, 2 mm = GRAFOAM FPA-10 SSE values ~125-155 g-1 cm3 for 4 mm GRAFOAM FPA-20, ~195-250 g-1 cm3 for 2 mm GRAFOAM FPA-10 Only 1-4 GHz


Compared to PF/CNT/Fe3O4 Foams Carbonised phenolic foam/2 wt% MWCNT/1-7 wt% Fe3O4 foam composites, d = 0.103-0.130 g cm-3, PF foam SSE ~ 120 g-1 cm3 CNTs only: SSE with 1 wt% CNT ~184 g-1 cm3, for 5 wt% CNTs SSE ~330 g-1 cm3

10.1016/j.carbon.2016.03.055


Compared to PF/CNT/Fe3O4 Foams PF/2wt% MWCNT/1-7 wt% Fe3O4 foams, d = 0.121-0.130 g cm-3 Left: thickness effect; Right: all 3 mm thick SSE with 1 wt% Fe3O4 ~315 g-1 cm3, for 7 wt% Fe3O4 SSE ~517 g-1 cm3

10.1016/j.carbon.2016.03.055


Conclusions: We have made MW Absorbers with the Highest Reported SSE values in the X-Band from Pyrolysed Waste Cork Material

Density (g cm-3)

SSE (-dB g-1 cm3) F (GHz)

3 mm pyrolysed cork

0.031

660-780

8-12

7 mm pyrolysed cork

0.031

950-1055

8-12

8.6 mm pyrolysed cork

0.031

1100-1235

8-12

3 mm PF/2% CNT /1% Fe3O4

0.127

~315

8-12

5 mm PF/2% CNT /7% Fe3O4

0.127

~555

8-12

3 mm PF/5% CNT

0.106

~330

8-12

3 mm carbon PF foam

0.104

~120

8-12

2 mm GF FPA-10

0.166

195-250

1-4


Thank you for your attention Acknowledgements: This work was carried out under the H2CORK project, FCT grant no. PTDC/CTMPTDC/CTMENE/6762/2014, as well as POCIPOCI-0101-01450145-FEDERFEDER-016862. Thanks are also due to Amorim Cork Composites, S.A. for donating the cork samples. RCP wishes to thank FCT grant IF/00681/2015 for supporting this work. This work was developed within the scope of the project CICECOCICECO-Aveiro Institute of Materials, POCIPOCI-0101-01450145-FEDERFEDER007679 (FCT UID/CTM /50011/2013), financed by national funds through the FCT/MEC and coco-financed by the EU with FEDER funds under the PT2020 Partnership Agreement.

www.ciceco.ua.pt/RobPullar

Our other work on pyrolysed cork materials with incredibly high surface areas = 1670 m2 g-1

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CSA - PRESENTATIONS OF THE SPEAKERS - DAY 2  

CORK IN SCIENCE AND APPLICATIONS CONGRESS -- From the Wine Industry to the New Applications Learn about the last innovations and researches...

CSA - PRESENTATIONS OF THE SPEAKERS - DAY 2  

CORK IN SCIENCE AND APPLICATIONS CONGRESS -- From the Wine Industry to the New Applications Learn about the last innovations and researches...

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