Patent ID: 6184291
Filing Date: 2001-02-06
Classification: C08L,C09D,C09J

Abstract:
A thermoplastic elastomeric composition comprising from about 70 to about 90 percent by weight, based on the total weight of the composition, of an unsaturated styrene triblock copolymer containing about 10 to 35 weight percent styrene and from about 10 to about 30 percent by weight, based on the total weight of the composition, of a homogeneously branched linear ethylene interpolymer characterized as an interpolymer of ethylene with at least one C.sub.3 -C.sub.20 .alpha.-olefin and as having a density from about 0.855 to about 0.905 g/cc and a short chain branching distribution index (SCBDI) of greater than 50 percent, wherein the homogeneously branched linear ethylene interpolymer in the amount employed is a substantially inert extender of the triblock copolymer and wherein the composition is further characterized as having:i. storage moduli throughout the range of -26.degree. C. to 24.degree. C. of less than about 3.5.times.10.sup.9 dynes/cm.sup.2,ii. a ratio of storage modulus at -26.degree. C. to storage modulus at 24.degree. C. of less than about 3, andiii. storage moduli at -26.degree. C. and 24.degree. C. about 0.4 to about 2.2 times higher than the storage moduli at -26.degree. C. and 24.degree. C., respectively, of the neat styrene block copolymer portion of the composition.