Emulsion graft copolymer useful for increasing impact strength of thermoplastic

摘要

Emulsion graft copolymer: (I) consists of (A) 5-18 wt.% of a first stage of (al) 85-99 wt.% methyl methacrylate (MMA), (a2) 1-15 wt.% 1-8C alkyl acrylate, (a3) 0-2 wt.% allyl methacrylate (ALMA) and (a4) 0-3 wt.% other di- or polyfunctional comonomers; (B) 25-35 wt.% of a second stage of (bl) 10-25 wt.% vinyl-aromatic monomers, (b2) 75-90 wt.% 1-20C alkyl acrylate and (b3) 0-3 WT.% ALMA; (C) 30-40 wt.% of a third stage of (cl) 15-27 wt.% vinyl-aromatic monomers, (c2) 73-85 wt.% 1-20 C alkyl acrylate and (c3) 0-3 wt.% ALMA; and (D) 15-30 wt.% of a fourth stage of (dl) 85-96 wt.% MMA, (d2) 3.8-10 wt.% 1-8C alkyl acrylate, (d3) 0-2 wt.% other di- or polyfunctional comonomers and (d4) 0.2-3 wt.% regulator; and the ratio of the amts. of vinyl-aromatic monomers (cl):(bl) is 1.3-1.9):1. Also claimed are thermoplastic compsns. contg. 10-60 wt.% (I); and mouldings, films or coatings contg. these compsns.