Synthesis and Properties of Poly(acrylic Acid) with Uniform Poly(methyl Methacrylate) Side Chains

Abstract

Copolymerization of the poly(methyl methacrylate) (PMMA) macromer with acrylic acid in dimethylformamide solution was studied using AIBN as initiator. The copolymers were purified by extractions with toluene and methanol successively and characterized with IR, ¹H NMR, and TEM. The graft copolymers exhibit good emulsifying properties which change with pH and behave as a good compatibilizer for the blending of epichlorohydrin rubber with poly(vinyl chloride) or PMMA. The addition of approximately 3% graft copolymer to the blends evidently improves their mechanical properties and causes the two T_g's to become closer. The blends of PMMA with epichlorohydrin rubber at a weight ratio of 6/4 with the addition of 2–4% graft copolymer show the mechanical properties of a thermoplastic elastomer.