The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 09, 1993
Filed:
Aug. 05, 1991
Sumitomo Chemical Company, Limited, Osaka, JP;
Abstract
A thermoplastic elastomer composition superior in moldability and appearance, little in anisotropy of mechanical properties, especially, tensile strength and retaining low temperature impact strength, is obtained by previously melt-kneading an intermediate composition comprising (a) 100 parts by weight of a selectively hydrogenated block copolymer which has at least two mono-alkenyl or mono-alkenylidene aromatic hydrocarbon polymer blocks A having a number-average molecular weight of 25,000-35,000 and at least one partially or completely hydrogenated aliphatic conjugated diene hydrocarbon polymer block B having a number-average molecular weight of 100,000-150,000, (b) 50-150 parts by weight of an extender oil and (c) 0-50 parts by weight of polypropylene I, then adding, to the kneaded intermediate composition, (d) polypropylene II containing at least 35% by weight of a propylene-ethylene block copolymer having a melt flow rate of 10-30 g/10 min. and an ethylene content of 3-15% by weight in such amount that total amount of polypropylene I plus polypropylene II is 200-400 parts by weight per 100 parts by weight of block copolymer (a) and then further melt kneading the mixture. Further addition of a filler to the composition can afford a thermoplastic elastomer composition of small linear expansion coefficient with retaining the above properties.