Kinetic features of radical polymerization occurring with auto-acceleration

Abstract

Within the framework of modern ideas on the dynamic properties of polymer solutions a theoretical analysis is made of the kinetic anomalies of radical polymerization at the auto-acceleration stage. The manifestation of these features is related to the dependence of the diffusion-controlled constant of bimolecular termination on conversion and the length of the terminated chains exceeding the critical size of the scale of the entanglements. Polymerization of the monomers of the alkylmethacrylate series is taken to look at the influence of a number of factors (concentration of initiator and transfer agent and the nature of the monomer) on the character of the manifestation of the gel effect and it is shown that fall in the termination constant results from reduction in the free volume of the reaction systems and the topological restrictions of the “network of entanglements”. Increase in the length of the alkyl radical of the monomers of the series studied diminishes the role of the topological restrictions in the termination reaction which leads to decline in the gel effect.