Styrenic Block Copolymers (TPS or TPE-S)
Thermoplastic elastomers described as TPS are compounds based on SBS or SEBS. In fact, the words SBS or SEBS are often used to describe these compounds when they are in fact raw materials. By describing compounds as SBS or SEBS it enables us to know the general level of performance and properties of the compound.
SBS is based on two-phase block copolymers with hard and soft segments. The styrene end blocks provide the thermoplastic properties and the Butadiene mid-blocks provide the elastomeric properties. SBS is probably the highest volume TPS material produced and is commonly used in footwear, adhesives and lower specification seals and grips, where resistance to chemicals and aging are not critical.
SBS, when hydrogenated, becomes SEBS, as the elimination of the C=C bonds in the butadiene component generated ethylene and butylenes mid-block, hence the SEBS acronym. SEBS is characterised by improved heat resistance, mechanical properties and chemical resistance. Dryflex and Mediprene compounds based on SEBS exhibit excellent weathering, UV and ozone resistance making them ideal choice for outdoor and long service life applications. SEBS based compounds adhere to engineering thermoplastics, when adhering to PP both SBS and SEBS can be used
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