MOLECULAR-MASS CONTROL IN METHACRYLIC COPOLYMER LATEXES CONTAINING GLYCIDYL METHACRYLATE

Results are presented on the preparation and characterization of batch emulsion copolymers of butyl methacrylate and glycidyl methacrylate ( GMA). The two main problems occurring during an emulsion copolymerizat ion with GMA are partial hydrolysis of the epoxy groups and internal c rosslinking of the latex particles formed. The influence of chain tran sfer agents (CTA) on the degree of crosslinking was investigated. Furt hermore, the effect of reaction temperature and the addition of methac rylic acid on the sol/gel content of the polymer formed and on the rat e of epoxy hydrolysis were investigated. It was found that lowering th e reaction temperature did not increase the sol content; however, it s ignificantly decreased the extent of hydrolysis. The addition of a CTA (especially CBr4) increased the sol content of the polymer, and good control over the molecular mass was achieved. The addition of methacry lic acid showed that this monomer can be used without any complication s with respect to the control of the sol content of the polymer formed . (C) 1996 John Wiley & Sons, Inc.