The copolymer of -methyl styrene (AMS) and maleic anhydride (MANH) was synthesized by self-stable precipitation polymerization.The resulting AMS-MANH copolymer was saponified and then served as macroinitiator and emulsifier for the further surfactant-free polymerization of methyl methacrylate (MMA).Surfactant-free emulsion polymerization of MMA was carried at 90℃.The AMS-MANH copolymer and the obtained block-copolymer were characterized by Fourier transform infrared spectroscopy (FTIR)
nuclear magnetic resonance (NMR)
gel permeation chromatography (GPC) and scanning electron microscopy (SEM).The results showed that the surfactant-free polymerization of MMA can be carried out by using saponified AMS-MANH copolymer
without any other initiator and emulsifier.Based on FTIR and 1H-NMR
the emulsion polymerization product was block copolymer of PMMA and AMS-MANH copolymer.During the process of surfactant-free polymerization of MMA
the polymerization rate increased along with the increasing of the concentration of macroinitiator.The maximum of polymerization conversion was 85% and the particle sizes ranged from 150 nm to 200 nm.The intrinsic viscosity number of the copolymer was about 80 mL/g.In addition
the intrinsic viscosity numbers of copolymers increased linearly with the rising of polymerization conversion.Based on the research results
a possible reaction mechanism has been proposed.This novel method is expected to be applied to other kinds of monomers.