The product group named SiBSTAR comprises thermoplastic elastomers that are block-copolymers made from styrene and isobutene (di- and tri-block SBC-types). A special feature is the combination of low hardness varying from Shore A25 to A46 in combination with gas barrier properties that define a new standard in the world of TPE. Some of the typical applications are in industries of food packaging, hoses, films, but also in the modification of other raw materials like e.g. EVOH, TPU, PA... Characteristics are:
- very low gas and water vapour diffusion rates
- low hardness (plasticizer free), soft-touch haptics
- high ageing resistance, good weatherability
- efficient damping behaviour, high loss factor (tan δ)
- high purity, low amount of extractables, low migration
The different types of SiBSTAR-elastomers can be distinguished by the ratio of polystyrene to PIB, i.e. by the molecular weight of each block in the copolymer. Both, extrusion and injection moulding processes can be utilized. SiBSTAR is supplied as transparent, free-flowing granules in bags of 20 kg.