Effect of chain length of the alkyl group of alkyl methacrylates on graft polymerization onto starch using ceric ammonium nitrate as initiator

Graft polymerization of methyl methacrylate (MMA), ethyl methacrylate (EMA) and n-butyl methacrylate (BMA) was carried onto starch using eerie ammonium nitrate (CAN) as initiator. Infrared spectroscopy and acid hydrolysis technique were used for confirmation of the graft copolymer formation. The grafting efficiency (GE) of the methacrylate towards grafting was found to be dependent on the concentration of the initiator and monomer, the reaction time and the temperature. The effect of increasing the alkyl group length from MMA to BMA through EMA on grafting was investigated and the relative reactivity was found to be: MMA > EMA > BMA. Representative graft copolymers were characterized by X-ray diffraction and thermogravimetric analyses. (C) 1997 Elsevier Science Ltd.