US 7,411,017 B2 · Thermoplastic elastomer and molded article thereof

Abstract

A thermoplastic elastomer excellent in rubber elasticity and extrudability and a molded object thereof. The thermoplastic elastomer comprises a partly or wholly crosslinked rubber (A), an isotactic polypropylene (B) having an isotactic pentad content of 0.8 or higher, a syndiotactic polypropylene (C) having a syndiotactic pentad content of 0.6 or higher, and a softener (D), the content of the syndiotactic of the syndiotactic polypropylene (C) being in the range of 0.5 to 10 wt. % based on the sum of the crosslinked rubber (A), isotactic polypropylene (B), syndiotactic polypropylene (C), and softener (D), the thermoplastic elastomer having a melt flow rate of 0.01 to 1000 g/10 min as measured in accordance with ASTMD 1238 at 230° C. under a load of 10 kg. The molded object is obtained by extrusion-molding the elastomer.

Claims15

Dependent claims

A thermoplastic elastomer comprising a rubber (A) which is partially or all crosslinked, an isotactic polypropylene (B) having an isotactic pentad ratio of 0.8 or more, a syndiotactic polypropylene (C) having a syndiotactic pentad ratio of 0.6 or more and a softener (D), wherein the syndiotactic polypropylene (C) is contained in an amounts of 0.5 to 10% by weight based on 100% by weight of the total amount of the crosslinked rubber (A), isotactic polypropylene (B), syndiotactic polypropylene (C) and softener (D),

wherein the ratio ((C)/(B)) by weight of the syndiotactic polypropylene (C) to the isotactic polypropylene (B) is greater than 0 and less than 1, and the thermoplastic elastomer has a melt flow rate of 0.01 to 1000 g/10 min., wherein the melt flow rate is measured at 230° C. under a load of 10 kg according to ASTM D1238.

A thermoplastic elastomer composition comprising a rubber (A) which is partially or all crosslinked, an isotactic polypropylene (B) having an isotactic pentad ratio of 0.8 or more, a syndiotactic polypropylene (C) having an syndiotactic pentad ratio of 0.6 or more, a softener (D), and a crosslinking agent (E),

wherein the syndiotactic polypropylene (C) is contained in an amount of 0.5 to 10% by weight based on 100% by weight of the total amount of the elastomer composition and the ratio ((C)/(B)) by weight of the syndiotactic polypropylene (C) to the isotactic polypropylene (B) is greater than 0 and less than 1, the crosslinking agent (E) is present in an amount of 0.01 to 0.9% by weight based on 100% by weight of the total elastomer composition, the thermoplastic elastomer having a melt flow rate of 0.01 to 1000 g/10 min., wherein the melt flow rate is measured at 230° C. under a load of 10 kg according to ASTM D1238.

Dependencies are inferred from the claim text.

Thermoplastic elastomer and molded article thereof

Life of this patent

Thermoplastic elastomer and molded article thereof

Life of this patent

Abstract

Claims15