Munich, Germany-based chemical group Wacker Chemie AG is showcasing its new self-adhesive liquid silicone rubber (LSR), Silpuran 6760/50,which has a low coefficient of friction (CoF) at this year’s COMPAMED medical technology trade fair.
Silpuran 6760/50 cures to form an elastomer with a low-friction surface, a property which enables self-adhesive LSRs to be used in novel applications. The silicone adheres readily to selected polyesters such as polybutylene terephthalate (PBT).
The low-CoF LSR has been designed for injection moulding, making hard/soft components for medical and pharmaceutical applications suitable for cost-effective large-scale production.
It is an addition-curing silicone rubber. It has two components and, once mixed, cures to form a transparent, mechanically robust elastomer with a 50 Shore A hardness.
After postcuring, the vulcanisate has a coefficient of friction which is between 50% and 70% lower than that of standard LSRs of comparable hardness. This makes it possible to use liquid silicone rubber in movable-seal applications. The low CoF also facilitates the fitting of silicone components into medical devices.
The liquid silicone rubber was specifically designed for the production of parts comprising hard/soft combinations such as those used in the pharmaceutical and medical sectors. They are often made from a hard thermoplastic, which determines the shape, encased in a soft plastic layer. Silpuran 6760/50 can be used to cost-effectively injection mould these kinds of parts in large series.
As a self-adhesive grade, it does not need any adhesion promoter. It adheres readily to selected polyesters, such as polybutylene terephthalate (PBT), a thermoplastic often used in injection moulding.
Silpuran 6760/50 also meets selected test requirements of ISO 10993 and United States Pharmacopeia (USP) Class VI. Postcured parts are suitable for food-contact applications and can be used under the recommendations of the German Federal Institute for Risk Assessment (BfR) and the US Food and Drug Administration (FDA).
The manufacturing process for all Silpuran silicone products entails ultrafine filtration, visual inspection and cleanroom packaging in antistatic materials. This ensures that Silpuran meets the special purity requirements of the food and medical-technology sectors.
COMPAMED medical technology trade fair takes place in Düsseldorf, Germany, from November 14 to 17.