Topochemical aspects of elementary reactions of the emulsion polymerization of acrylonitrile

Abstract

A combination of statistic and kinetic methods of analysis is used to collect quantitative data on the kinetics of elementary reactions of growth and termination of kinetic chains in each phase of a heterophase system as well as on interfacial mass exchange at the quasistationary stage of radiation-induced emulsion polymerization of acrylonitrile. It is found that, in the system, a steady-state concentration of polymer—monomer particles is attained, and these particles are able to increase their dimensions with an increase in monomer conversion. Activation of particles and chain termination on particles are due to the entrapment of macroradicals from water. As a result of a gradual increase in the dimensions of polymer-monomer particles and a decrease in the monomer concentration in the aqueous phase, the adsorption layer of acrylonitrile becomes so thin that, at the final stage, monomolecular layers lose integrity and the conditions of quasi-stationarity are violated.