ABS-type polymer composition for production of molded parts, e.g. casings, contains at least two graft copolymers based respectively on fine and coarse polybutadiene lattices obtained by seed polymerization

摘要

ABS-type polymer composition contains two graft copolymer rubbers obtained by emulsion polymerization of styrene and acrylonitrile in presence of fine and coarse butadiene polymer lattices (A and B) made by seed polymerization, using a latex with a particle size of 10-220 nm as the seed latex and also as base latex (C) for production of an optional third graft copolymer. Polymer compositions (PC) containing: (I) graft copolymer rubber(s) obtained by the emulsion polymerization of styrene (S) and acrylonitrile (AN) in a wt. ratio of (95:5)-(50:50) (either or both of which may be partly or completely replaced by alpha -methylstyrene, methyl methacrylate and/or N-phenylmaleimide) in presence of a butadiene polymer (PB) latex (A) with an average particle diameter (d50) of 230-330 nm; (II) graft copolymer rubber(s) obtained by polymerisation of (S) and (AN) as above in presence of a PB latex (B) with a d50 of 340-480 nm; optionally (III) other graft copolymer rubber(s) obtained by polymerization of (S) and (AN) as above in presence of a PB latex (C); and (IV) rubber-free copolymer(s) of (S) and (AN) (and/or other monomers as above) in a wt. ratio of (95:5)-(50:50). Lattices (A) and (B) are produced by seed polymerization using a PB latex (C) with a d50 of 10-220 nm as seed latex and component (III) is obtained by graft polymerisation in presence of (C) as the seed latex. Independent claims are also included for: (a) a process for the production of PC in which the butadiene polymer lattices (A), (B) and component (III) are obtained by the method described above; (b) a process for the production of PC my mixing components (I), (II), optionally (III), and (IV) and then compounding and extruding at elevated temperature; (c) molded parts obtained from PC.