Abstract: In this paper the graft copolymerization of onjac flour and butyl acrylate was studied using initiat ing reagent of ceric amonium nitrate. It was showed that the product viscosity was greatly affected by the con centration of initiator and monomer, reactiing time and temperature. The viscosity fo the graft copolymer was 99% higher than that fo unmodified konjac flour using the concentration of butyl acrylate 2.1×10(-1)mol/L, [Ce(4+)]=2.0×10(-3)mol/L, and reacting 2h at 30℃. When oranges were soaped using 1.0% graft copolymer and the keep them fresh for 130 day at room temperature, the water loss of the orange decreased 36.2% , the rate of rotte decreased 89. 6% , the 1oss of Vc content decreased53. 5%, breath intensity decreased 55. 5% compared with using unmodified konjac flour.

Key words: Konjac flour Butyl acrylate Graft copelymerization