Study on the kinetics of copolymerization of N-p-substituted phenyl maleimides with styrene in solution

With DMF as solvent,the kinetics of copolymerization systems of four N-p-substituted phenyl maleimides with styrene in solution was systematically studied by means of dilatometry. The polymerization rate equation of N-phenyl maleimide with styrene is R-p = k [I](1/2)[M]. The polymerization rate of other N-p-substituted phenyl maleimides with styrene were also a linear function of monomer concentration. The overall apparent copolymerization rate constants and apparent copolymerization activity energy of the four N-p-substituted phenyl maleimides with styrene were determined,which confirmed that the polymerization activity of the four N-p-substituted phenyl maleimides with styrene decreases in an order as follows:N-p-chlorophenyl maleimide, N-phenyl maleimide, N-p-tolylphenyl maleimide and N-p-tolyloxyphenyl maleimide. The apparent copolymerization activity energy of N-p-chlorophenyl maleimide with styrene was the smallest because the polarization difference between N-p-chlorophenyl maleimide and styrene was the biggest. The result was in accordence with the theory of CTC complex, which provided the evidence of the existence of CTC complex.