PURPOSE: To obtain a modified block copolymer being capable of forming a molding material suitable for combining a styrene polymer therewith, by combining a molecular unit contg. a carboxylic acid group with a block copolymer consisting of vinyl arom. compd. polymer blocks and olefin compd. polymer blocks and having a low degree of unsaturation.
CONSTITUTION: This modified block copolymer is prepf. from at least two vinyl arom. compd. polymer blocks A and at least one olefin compd. polymer blocks B whose degree of unsaturation is less than 20% and molecular units contg. 0.05W20pts.wt. dicarboxylic acid or its deriv. group are combined with the block copolymer wherein the content of the vinyl arom. compd. is 10W90wt.% and whose no.-average MW is 20,000W500,000 based on 100pts.wt. above-described block copolymer. Styrene is preferable as the vinyl arom. compd. butadiene and/or isoprene are preferable as the olefin compd. and maleic anhydride is preferable as the dicarboxylic acid group or its deriv.-contg. compd.
MORITA HIDEO
HAYANO FUSAKAZU
| JPH0215569A | 1990-01-19 |