Patent ID: 6506842
Filing Date: 2003-01-14
Classification: C08L

Abstract:
A rheology-modified, substantially gel-free thermoplastic elastomer composition comprising at least one elastomeric, linear or substantially linear, ethylene/alpha-olefin polymer or ethylene/alpha-olefin polymer blend and at least one polymer selected from polypropylene homopolymers and propylene/ethylene copolymers, wherein the rheology is modified by way of a free radical generating compound, radiation or application of heat, the thermoplastic elastomer composition having at least three of four characteristics, the characteristics being a shear thinning index of at least 20, a melt strength that is at least about 1.5 times that of the composition without rheology modification, a solidification temperature that is at least 10Â° C. greater than that of the composition without rheology modification, and an upper service temperature limit that is at least 10Â° C. greater than that of the composition without rheology modification, said thermoplastic elastomer composition having an insoluble gel content, as determined by ASTM D 2765-90, method B, below detectable limits when using xylene as a solvent, said elastomeric polymer having a density up to about 0.92 g/cc and said elastomeric polymer blend having a density up to about 0.91 g/cc.