Thermoplastic Elastomers
Kraiburg’s Thermolast M is approved for use in direct contact with blood and medications
The materials are certified according to DIN ISO 10993-5 (cytotoxicity), -10 (intracutaneous irritation), -11 (acute system toxicity), USP Class VI and DIN ISO 10993-4 (hemolysis). Plus, Kraiburg says its compounds can conform to cleanroom processing standards, are able to be sterilised with gas, radiation, plasma and permit steam sterilisation. US firm Kraton Performance Polymers, a producer of styrenic block copolymer (SBC), has developed Kraton G1653 polymer, a styrene-ethylene-butylenestyrene (SEBS) block copolymer, with a lower molecular weight than Kraton G1652 polymer, but with high tensile strength and toughness of G1652 while offering lower melt and solution viscosities. Kraton says the low solution viscosity increases solid content and decreases VOC of solvent based products, yet maintains similar processability. For coating applications, the increased solid level translates to potentially reduce coating layers and lower labour costs. For sealant applications, the increased solid content is expected to reduce shrinkage and costs associated with solvent. G1653 also can be dissolved in PCBTF at 20% solids, which may enable formulators to replace organic solvents with PCBTF to reduce VOCs associated with the final product. The free flowing dense pellet form of G1653 is expected to improve storage, handling, and feeding of the polymer in comparison to SEBS polymers in powder form. Potential market applications include coating applications, sealants, pressure sensitive adhesives, hot melt adhesives, TPE compound, elastic compound, medical compound, colour master batch, additive concentrates, oil gel, and polymer modification. Since G1653 has the same low rubber phase Tg (-48.5°C) as the conventional G1600 series polymers, it allows the polymer to remain flexible and elastic at low temperatures. When compounded with a random co-PP and extruded into clear films, the robustness is especially useful for medical applications, says Kraton. These films can be heat sealed and sterilised.
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MARCH / APRIL 2017
Providing soft touch treatment TPEs serve the market requirement for soft feel/touch application and this is a vital aspect especially for medical devices. The use of sedation in medical procedures is increasing as a result of more sophisticated surgical techniques, an ageing population, and a greater incidence of obesity. Thus, US-based Revolutionary Medical Devices (RMD) has developed the first nasalonly oxygenation mask, SuperNO2VA, which uses Teknor Apex’s Medalist MD-10105. Unlike full-face masks, SuperNO2VA provides easy access to the oral cavity and is designed to deliver a greater flow of oxygen under positive pressure to the patient’s airways. The single-use mask consists of a transparent rigid PP component with access ports for an anesthesia circuit or hyperinflation bag, plus a TPE cushion that is over-moulded onto the PP structure. RMD uses the China-based contract moulding subsidiary of a US company to injection mould the components for the SuperNO2VA mask. The cushion part is produced in blue, green, pink, or yellow for purposes of colour-coding, with Medalist MD-10105 supplied in pre-coloured compounds. RMD has also recently obtained a patent for its SuperNO2VA mask. Foot care aid for athletes TPEs can also aid athletes whose primary opponent is foot ailment. Gel technology specialist Silipos recently launched Silipos Active, a new line of foot support products for prevention and relief of pain associated with a variety of common ailments. The US-headquartered firm stated that the TPE gel line includes 16 different products that help prevent and treat a variety of issues such as corns, calluses, ingrown toenails, blisters, bunions, Achilles tendonitis, bursitis, sprains, and general foot pain. Silipos is the original manufacturer of podiatry TPE gels, which are made with a proprietary formula of medical-grade mineral oil. In comparison, many other gel products are made from less refined oil, which contain a higher number of impurities and toxic substances, says Silipos.
Silipos has introduced Silipos Active, a new line of foot support products made of TPE gels