Features of the ionization equilibrium of amine groups in macromolecules of copolymers of N-vinylamides with allyl and vinylamines in aqueous solutions

Abstract

A significant decrease in amino group basicity (23·5 pK a units) in copolymers of N-vinyl-methylacetamide, N-vinyl pyrrolidone and N-vinylcaprolactam with allyl or vinyl amines, when these are present in the chain in small amounts (0·25-10%), compared with the basicity of their low-molecular weight analogues is observed. The nature of the relation between pK a app and α i for the copolymers studied can be explained in terms of the microheterogeneity of the amino groups with respect to aid-base properties. Addition of salts does not change these relations significantly.