Synthesis of alpha,omega-vinyl telechelic polyurethane macromonomer and preparation of polyurethane-poly(methyl methacrylate) copolymer emulsions via RAFT emulsion polymerization)

摘要

In this study, alpha,omega-vinyl telechelic polyurethane macromonomers used as macromonomer and stabilizer of emulsion system were synthesized by reaction of poly(propylene glycol), 4,4-diphenylmethane diisocyanate (MDI), 2,2-dimethylolbutanoic acid (DMBA), diethylene glycol, and 2-hydroxyethyl acrylate (HEA). Different compositions of methyl methacrylate (MMA) and alpha,omega-vinyl telechelic polyurethane macromonomers were successfully carried out reversible addition-fragmentation chain transfer radical polymerization (RAFT) mediated by RAFT agent, 2-(dodecylthiocarbonothioylthio) propanoic acid. It was demonstrated that the waterborne polyurethane (WPU)-poly(methyl methacrylate) copolymer emulsions prepared by RAFT emulsion copolymerization exhibited enhanced storage stability. No precipitation was observed for longer than sixmonths during the storage at ambient temperature for all the copolymer emulsions. With increase in addition amount of MMA, the electrolyte stability became worse. The water-resistance property and mechanical property of the WPU/poly(methyl methacrylate) copolymer films were improved obviously.