Predicting network formation of free radical polymerization of multifunctional monomers

Free radical polymerization of multifunctional monomers leads to the formation of crosslinked polymer materials. These crosslinked polymers are heterogeneous networks caused by varying pendant reactivity and primary cyclization reactions. A kinetic model was utilized to probe the manner in which pendant double bonds react throughout the polymerization and to characterize the cycle size. The effects of crosslinking agent size, copolymerization, and solution polymerization were each examined. Increasing crosslinking agent size causes fewer small cycles to form and diminishes the total number of cycles that are created. Increasing the solvent concentration during polymerization has the converse effects of increasing the number of cycles that form within the first couple of repeat units and increasing the total fraction of pendants that form cycles. The model was further used to predict the molecular weight between crosslinks as a function of polymerization conditions.