Kinetics of n-phenlymaleimide/styrene/acrylonitrile/ α-methylstyrene emulsion copolymerization

N-phenylmaleimide/styrene/acrylonitrile/a-methylstyrene emulsion copolymerization was studied using solium dodecyl sulfate (SDS) as emulsifier and potassium persulfate (KPS) as initiator. The effects of monomers ratio, reaction temperature, emulsifier and initiator concentration on the rate of copolymerization were investigated. It showed that the overall observed copolymerization activation energy of the system was 84.14kJ/mol; and the rate of copolymerization was positively proportion to the concentration of emulsifier to the power of 0.46 and to the concentration of initiator t the power of 0.57. For the emulsion copolymerization, the suitable reaction condition were: polymerizing for 1h at 75°C, aging for 2h at 85°C, SDS 8.4 mmol/L and KPS 1.8 mmol/L. The mole fracion of α-methyl-styrene had a great influence on the reaction rate, should be controlled under 20%mol.