Synthesis and Characterization of Starch-g-poly(methyl methacrylate-co-styrene) Copolymer Prepared via Emulsion Polymerization

This investigation reports the synthesis and characterization of a graft copolymer of methyl methacrylate (MMA) and styrene (Sty) onto starch.  The copolymers of MMA with Styrene, P(MMA-co-Sty) and the graft copolymer, Starch-g-P(MMA-co-Sty) were prepared via emulsion polymerization using the thermal initiator potassium persulfate (KPS). Sodium dodecyl sulfate (SDS) was used as a surfactant in both cases. The polymerizations were carried out at 70ºC for 30 minutes for P(MMA-co-Sty) and 3 hours for Starch-g-P(MMA-co-Sty). Attempts had also been made to prepare copolymers with different monomer compositions. The progress of the polymerizations with time was monitored by measuring the conversion of monomers gravimetrically. The grafted Starches were characterized by Nuclear Magnetic Resonance (1H-NMR) and Fourier Transform InfraRed (FT-IR) spectroscopy analyses. The FT-IR and 1H NMR analysis of the purified copolymers revealed successful grafting of MMA and Styrene copolymerization onto Starch. The surface morphology was studied by SEM and the thermal study of the graft copolymer was studied by TGA.