Modified block copolymer composition

A modified block copolymer composition comprising:

• (a) at least one thermoplastic polymer selected from the group consisting of polar thermoplastic polymers each containing at least one polar functional group, polyoxymethylenes, polycarbonates, modified polycarbonates, polysulfones, modified polysulfones, nitrile polymers, polyphenylene ethers, modified polyphenylene ethers, polyarylene sulfides and modified polyarylene sulfides and
• (b) at least one modified block polymer which comprises a base block copolymer of at least one monovinyl substituted aromatic hydrocarbon polymer block A and at least one olefin compound polymer block B having an ethylenic unsaturation degree not exceeding 20%, said base block copolymer having at least one molecular unit grafted thereto, said at least one molecular unit containing at least one member selected from a carboxylic acid group and groups derived therefrom, said monovinyl substituted aromatic hydrocarbon being contained in said base block copolymer in an amount of over 60% by weight up to 95% inclusive by weight based on said base block copolymer, said at least one thermoplastic polymer (a) being present in a weight ratio of 90:10 to 5:95 relative to said at least one modified block copolymer (b),
• said polar thermoplastic polymers excluding said modified block copolymer (b).