| abstract |
[PROBLEMS] To improve the heat resistance of a conventional ethylene-aromatic vinyl compound copolymer, and further has excellent crystallinity of ethylene, transparency and elastic recovery compared to a conventional cross copolymer, It is an object of the present invention to provide a novel cross copolymer and a resin composition having a small film anisotropy. A production method comprising a polymerization step comprising a coordination polymerization step and an anion polymerization step, wherein as a coordination polymerization step, ethylene, an aromatic vinyl compound and an aromatic polyene are produced using a single site coordination polymerization catalyst. Copolymerization is performed to synthesize an ethylene-aromatic vinyl compound-aromatic polyene copolymer, and then, as an anionic polymerization step, the ethylene-aromatic vinyl compound-aromatic polyene copolymer and an anion-polymerizable vinyl compound monomer In the presence of an anionic polymerization initiator, and a method for producing a cross-copolymer. [Selection figure] None |