Study on the Stability of Starch/Acrylamide Inverse Emulsion and the Graft Copolymerization

The water-oil inverse emulsion was prepared in present of cassava starch and acrylamide with the compounds of span80 and tween80 as emulsifier.The effect factors on the types and stability of the inverse emulsion were discussed,and the optimum conditions for forming stable water-oil inverse emulsion were attained as the HLB value of mixed emulsifier at 6.49,the mass ratio of oil to water in 1∶1,and the content of the mixed emulsifier at 3%.The graft copolymerization of acrylamide onto cassava starch was conducted successfully in above inverse emulsion.By orthogonal experiment the optimum conditions were determined as temperature at 50 ℃,time in 2 h,the concentration of initiator in 0.0175 mol/L,and mass ratio of acrylamide to starch in 3∶2.The rate of polymerization and the graft efficiency were 95.46 % and 95.10 % respectively.