Comolded multi-layer monovinylaromatic/conjugated diene block polymer blend system, and shaped articles derived therefrom

摘要

A comolded multi-layered polymer blend system, comprising: at least two layers, each layer having a continuous polymer network of an optionally hydrogenated block copolymer which comprise at least two terminal polymonovinylaromatic blocks and at least one central polyconjugated diene block, and at least one of said layers comprising the continuous polymer network of the block copolymer further comprises a co-continuous rigid polymer phase consisting of a homopolyalkylene or a copolymer of alkylenes having from 2 to 10 carbon atoms; wherein the two layers are in intimate contact with each other; wherein the layers have different contents by weight of the block copolymers; and wherein an extender is present in each polymer network such that the final weight ratio of the block copolymer and the extender in each layer is the same. This comolded multi-layer polymer blend system is used to make air bags for automotive safety systems.