Abstract:
Graft copolymerizations of glutinous starch and methyl methacylate were synthesized by free radical polymerization using benzoyl peroxide as an initiator in aqueous medium at 80 C. The formation of graft copolymers was confirmed by analyzing the obtained products with Fourier transform infrared spectroscopy (FT-IT) and scanning and scanning electron microscopy (SEM). The effects of the amount of glutinous starch, the amount of methyl methacrylate monomer, the amount of benzoyl peroxide and reaction time on grafting characteristics were studied. It was found the the optimum conditions for grafting was obtained when 5 g. of glutinous starch, 5 g. of methyl methacrylate monomer, 0.1 g. of benzoyl peroxide and the reaction time of 2 hours were used. This condition provided a graft copolymer having 80.40 percent monomer conversion, 81.98 percent yield, 49.50 percent homopolymer formation, 50.50 percent grafting efficiency, 42.38 percent grafting ratio and 32.27 percent add-on. The obtained graft copolymer exhibited thermal decomposition temperature that was comparable to those of glutinous starch and reference PMMA.