Multi-layer composite interpolymers characterized by a heterogeneous particle distribution, process for their preparation, and reinforcement of thermoplastic matrix

摘要

This multilayer interpolymer material comprises an internal, elastomeric, stage polymerised from 50-99.9 parts of at least one of: conjugated dienes and alkyl and aralkyl acrylate; (b) 0-49.9 parts of at least one copolymerisable monomer; (c) 0.05-8 parts of at least one crosslinking monomer; and (d) 0.05-6 parts of at least one grafting monomer; and an external nonelastomeric stage, polymerised from (a) 50-99.9 parts by weight of at least one from: alkyl methacrylates, vinylaromatic hydrocarbons and unsaturated nitriles; (b) 0.1-50 parts of at least one copolymerisable monomer; and (c) 0-5 parts of at least one chain-limiting agent, the parts being given by weight, it being possible for the said polymer to contain a core stage which is nonelastomeric or elastomeric without grafting and crosslinking monomers. Two populations of particles with a mean diameter of approximately 40-150 nm and approximately 160-500 nm respectively are mixed in given ratios. The impact strength of the resulting matrices is thus improved.