| 摘要 |
PROBLEM TO BE SOLVED: To obtain a resin composition comprising a specific block copolymer mixture and a styrenic resin and having a good gel level and an excellent physical property balance. SOLUTION: This resin composition comprises (A) a block copolymer mixture comprising block copolymers having at least two vinyl aromatic hydrocarbon polymer blocks and at least one polymer block consisting mainly of a conjugated diene and (B) a styrenic resin in a weight ratio of 5/95 to 70/30. The component A has a vinyl aromatic hydrocarbon content of 65-85 wt.%, a conjugated diene content of 35-15 wt.%, a number-average mol.wt. of 50,000-300,000, and a weight- average mol.wt./number-average mol.wt. of 1.2-2.5. The vinyl aromatic hydrocarbon content of the block copolymer constituting the block copolymer mixture has a composition distribution wherein the vinyl aromatic hydrocarbon content continuously increases within equations I and II [B is the vinyl aromatic hydrocarbon content (wt.%) of the block copolymer having a mol.wt. of M in the component A; BO is the vinyl aromatic hydrocarbon content (wt.%) of the component A; M is the mol.wt. of the block copolymer], as the mol.wt. of 70,000-300,000 increases.
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