KINETIC FEATURES OF RADICAL POLYMERIZATION PROCEEDING WITH AUTOACCELERATION

In the framework of the modern concept of dynamic properties of polymer solutions the kinetic anomalies of radical polymerization on the autoacceleration stage have been theoretically analysed. These features are related with the dependence of the diffusion-controlled constant of the bimolecular termination on conversion and on the length of terminating chains exceeding the critical size of entanglements. For polymerization of alkylmethacrylic monomers the effect of some factors (initiator concentration, chain transfer agent concentration, monomer nature) on the character of the gel-effect manifestation is described. Decrease of the termination constant is shown to proceed as a result of the decrease of the free volume of reaction systems and topological limitations of the <<entanglements network>>. An increase of the length of the alkyl radical of monomers under study decreases the role of topological limitations in the chain termination reaction resulting in the decrease of the gel-effect.