Graft copolymers with improved oil acceptance.

摘要

A graft copolymer (I) comprises poly (styrene- b-butadiene- g-alpha-methyl styrene). Pref. (I) has at least 2 graft branches per backbone, contains 5-15 wt. % of styrene and 5-60 wt. % of alpha-methyl styrene, and has butadiene blocks with Mn of 3000-25000, styrene blocks with Mn of 25000-210000 and alpha-methyl styrene branches with Mn of 30000-200000.. (I) has improved oil acceptability with amts. of oil up to 44 pts./100 pts. of butadiene and a tensile strength of 12-18 MPa.(I)isathermoplasticelastomer.