CORE-SHELL STRUCTURED LATEX-PARTICLES .1. COPOLYMERIZATION OF STYRENESBENZYL METHACRYLATE AS A CHOICE FOR SHELL MATERIAL AND CHARACTERIZATION OF POLY(N-BUTYL ACRYLATE) CORE LATEX-PARTICLES

Composition, molecular weight, and microstructure of the ''shell'' pol ymer in core-shell structured latex particles, designed for toughening polycarbonate matrix, should be controlled for enhanced miscibility b etween the shell polymer and the matrix. Various ''shell polymer'' sys tems based on styrene (St) and benzyl methacrylate (BM) were synthesiz ed. Reactivity ratios were determined for (St) and (BM). Chain transfe r efficiency studies revealed the susceptibility of styrene to transfe r to a chain transfer agent. Benzyl methacrylate was found to have ste ric and stability factors hindering its tendency to chain transfer wit h various chain transfer agents. Miscibility tests between P(St/BM) an d polycarbonate (PC) indicated different degrees of miscibility, depen ding upon polymerization conditions, Factors other than molecular weig ht, such as branching and crosslinking, were found to play a role in t he miscibility. Monodisperse poly(n-butyl acrylate) (PEA) seed latex p articles of variable degree of crosslinking and particle size were suc cessfully synthesized by batch emulsion polymerization. (C) 1995 John Wiley & Sons, Inc.