A QUALITATIVE CRITERION PROVING THE PARTICIPATION OF COMONOMER COMPLEXES IN THE CHAIN PROPAGATION OF RADICAL COPOLYMERIZATION

The juxtaposition of the equations for copolymer composition for chain propagation following the terminal (T), penultimate (P) and complex ( C) mechanisms shows that the copolymer composition depends on the tota l comonomer concentration only when a comonomer complex participates i n the propagation. This makes it possible to define an easily applicab le criterion proving comonomer complex participation yet not excluding propagation according to the T and P mechanisms. The criterion has be en tested for the copolymerization of 1-vinyl-2-pyrrolidone with acryl ic and methacrylic acids, and of styrene with maleic anhydride. It has been shown that such a dependence cannot be claimed for styrene-methy l methacrylate copolymerization. (C) 1998 SCI.