| 摘要 |
PROBLEM TO BE SOLVED: To provide a resin composition rich in flexibility, excellent in air permeation resistance and moisture permeation resistance, having good injection moldability and capable of injection molding. SOLUTION: The resin composition having air permeability, moisture permeability, hardness and MFR each within a specific range is obtained by blending (A) a (b)-(a)-(b) type isobutylene-based triblock copolymer with a weight average molecular weight of 50,000-80,000 having (a) a polymer block essentially consisting of isobutylene units and (b) a polymer block essentially consisting of styrene units and (B) a (d)-(c)-(d) type isobutylene-based triblock copolymer with a weight average molecular weight of 90,000-130,000 having (c) a polymer block essentially consisting of isobutylene units and (d) a polymer block essentially consisting of styrene units, at a mass ratio of (A) to (B) of 20:80-60:40. COPYRIGHT: (C)2006,JPO&NCIPI
|
