Patent ID: 7435776

Claim:
A thermoplastic elastomer (“TPE”) composition for overmolding a predominantly nylon substrate consisting essentially of, an essentially polyamide-free blend of, (a) an inert filler present in an amount in the range from 5 to 40% by weight of the composition, (b) from 10-45 parts of a plasticizer per 100 parts of formulated composition, unreactive with an ingredient in the composition, the plasticizer selected from the group consisting of paraffinic oils, olefin oligomers and low Mw polymers; (c) a block copolymer selected from the group consisting of (C1), a polystyrene-polydiene-polystyrene block copolymer (SDS rubber), or an at least partially hydrogenated polystyrene-polydiene-polystyrene block copolymer (SHDS rubber), the SDS and SHDS each having “small” polystyrene endblocks, one at each end of a polydiene midblock, which midblock includes a controlled distribution block of polystyrene, the “small” polystyrene endblocks being together present in an amount in the range from about 20% to 30% by weight of the block copolymer, not including the polystyrene in the polydiene midblock, so that (C1) has a weight average molecular weight (“Mw”) high enough to be thermally stable at 282° C. (540° F.), (C2), a functionalized at least partially hydrogenated “high rubber” SHDS having a functionality of essentially 1%, the “small” endblocks together present in an amount in the range from about 8-25% by weight, and (C3), a functionalized at least partially hydrogenated SHDS having a functionality of >1% but <2%, in which the end blocks are together present in an amount in the range from >25%-35% by weight; in any combination, provided that only (C2) may be present by itself, (C1) and (C3) always requiring at least one of the other block copolymers in combination; (d) from 0-30% by weight of the composition, of a functionalized polyolefin (FP), the olefin having from 2 to 8 carbon atoms; (e) from 0-15% by wt of the composition, of a hydrogenated nonfunctionalized hydrogenated polystyrene-polydiene-polystyrene (SHDS) block coplymer; and, (f) an additive to enhance the useful life of the composition.