The Characterization of In-situ Graft Copolymer Formed in Polystyrene/Poly(methyl methacrylate-ran-glycidyl methacrylate) Blend with Mono-carboxylated Polystyrene as a Compatibilizer

The poly(methyl methacrylate)-graft-polystyrene (PMMA-g-PS) copolymer formed in situ from polystyrene(PS)/poly(methyl methacrylate-ran-glycidyl methacrylate) (PMMA-GMA) blend with monocarboxylated PS (PS-mCOOH) as an in-situ compatibilizer in molten state was characterized by using -nuclear magnetic resonance spectroscopy and gel permeation chromatography. These analyses were done after the phase consisting of unreacted PMMA-GMA and PMMA-g-PS copolymer was successfully separated from the other phase consisting of PS and unreacted PS-mCOOH by solvent extraction. The copolymer concentration in total blend (blend) increased linearly with the initially added amount a single PS-mCOOH chain was on the average grafted onto a single PMMA-GAM chain, although PMMA-GMA has 12 reactive sites per chain.