Substituent Effects in the Kinetics of Polymerization of Acrylonitrile Retarded by Substituted Chalcones

Substituent effects in the kinetics of polymerization of acrylonitrile retarded by substituted chalcones are studied in terms of Hammett-type correlations with sigma-plus and also in terms of the field and resonance components of the substituents. With the modified sigma-plus values for halogen substituents, both the correlations are found to give excellent results. The significance of the values of the observed reaction constants and the relative merits of the two types of correlations are discussed, We have earlier reported [ 11 the kinetics of the Ce(IV)-initiated polymerization of acrylonitrile by chalcone, in which it was proposed that the polymerization of acrylonitrile by Ce(Iv) is retarded by a radical produced by the interaction of chalcone with Ce(IV). The following reaction scheme, which satisfactorily accounted for all the observed kinetic results, was proposed.