Patent ID: 8513347

Claim:
A thermoplastic elastomer composition comprising: (i) at least one low molecular weight polyalphaolefin comprising oligomers of C 5 to C 18 olefins, wherein the polyalphaolefin has a number average molecular weight, Mn, of 300 to 15,000 g/mol, a kinematic viscosity of 10 cSt or more at 100° C., a pour point of −20° C. or less according to ASTM D97, a flash point of 200° C. or more according to ASTM D56, a specific gravity of 0.855 or less, and a viscosity index of 130 or more; (ii) 10.0 to 30.0 wt % of a block copolymer obtainable by selectively hydrogenating a block copolymer having terminal polymeric blocks of a vinyl aromatic monomer and a mid-block prepared originally with an olefin and subsequently hydrogenated; and (iii) 5.0 to 50.0 wt % of polypropylene having a weight average molecular weight, Mw, of 30,000 to 2,000,000 g/mol; wherein the wt % are based on the total weight of the composition; and (iv) with the proviso that when (i) is a PAO having a number average molecular weight, Mn, of between about 400 and 1000 g/mole: (a) (iii) is a homopolymer characterized by an MFR greater than 2 g/10 min under 2.16 kg load, or (b) (iii) is a copolymer; or (c) (iii) is a polymer or copolymer made by a metallocene catalyst; or (d) the composition does not contain calcium carbonate; and (v) wherein the composition after aging at 125° C. in air for 5 days has all of the following parameters: (a) decrease in 100% Tensile Modulus of less than 15%; (b) decrease in Tensile Strength of less than 55%; (c) decrease in Elongation at Break of less than 25%; and (d) decrease in Toughness of less than 60%, and the decrease is measured relative to the original sample prior to aging.