Claims
- 1. An improved rigid thermoplastic composition, wherein the composition comprises from 60% to 95% by weight of the polymer components of a graft copolymer comprising about 10% to 65% by weight of the graft copolymer of a polystyrene grafted onto a backbone of polypropylene, and from 40% to 5% by weight of the polymer components of a rubber component comprising from 20% -100% of the rubber component of one or more elastomeric block copolymers, wherein the improvement comprises selection of a selectively hydrogenated block copolymer having the structure styrene-hydrogenated isoprene-styrene' (S-EP-S') or styrene-hydrogenated butadiene-styrene' (S-EB-S'), wherein the block copolymer has a total peak molecular weight from 30,000 to 150,000 and wherein the peak molecular weight of the S block is greater than the peak molecular weight of the S' block by at least 50%.
- 2. The composition of claim 1, wherein the peak molecular weight of the S block is from 4,000 to 10,000.
Parent Case Info
This is a division of application Ser. No. 08/150,936, filed Nov. 10, 1993, U.S. Pat. No. 5,378,760.
US Referenced Citations (12)
Foreign Referenced Citations (1)
Number |
Date |
Country |
0449087A2 |
Mar 1990 |
EPX |
Non-Patent Literature Citations (1)
Entry |
Fetters, L. J. "Synthesis and Characterization of Block Copolymers by Anionic Polymerization", in Meier, D. J., Block Copolymers, Science and Technology (New York, Harwood, 1983), pp. 17-38. |
Divisions (1)
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Number |
Date |
Country |
Parent |
150936 |
Nov 1993 |
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