METHOD FOR PRODUCING GRAFT COPOLYMERS, CONTAINING AN ELASTIC GRAFT COPOLYMER BACKBONE

摘要

The invention relates to a method for producing graft copolymers, containing an elastic copolymer backbone. In a first stage of said method, a) ethene, as the principal monomer, is copolymerised co-ordinatively with an alpha -olefin which is substituted with an alkoxyamine group as the additional comonomer in the presence of a transition metal compound which has been complexed using a bisimin chelate ligand, into an elastomeric graft copolymer backbone. In a second stage b) the copolymer produced in a) is reacted under controlled radical polymerisation conditions in the presence of monomers, selected from the group of vinyl aromatic compounds, vinyl heteroaromatic or vinyl heteroalicyclic compounds, alkyl esters, and amides of (meth)acryl acid, acryl nitrile, methacryl nitrile, maleimide or vinyl ferrocene and optionally also reacted in the presence of conjugated organic dienes, involving the formation of covalently linked graft branches. In a further stage c) the graft copolymer obtained in b) is either directly isolated, or the alkoxyamine groups which terminate the graft polymer lateral branches are first removed under reductive reaction conditions and the graft polymer thus obtained is subsequently isolated.