Pulse radiolysis studies on short-lived intermediates in radiation-induced polymerization of bulk styrene and methanol-styrene solutions

Primary processes of radiation-induced polymerization of bulk styrene at room temperature and effects of methanol have been studied by means of pulse radiolysis. Cationic intermediates such as the bonded dimer cation radical, which is the initiating species of radiation and photo-induced cationic polymerization, have been directly observed for the first time in bulk styrene. The rate constant of the reaction of the bonded dimer cation radical with a styrene monomer (trimerization and the first step of the cationic polymerization) has been directly determined to be the order of 10⁶M^-1sec^-1. Methanol reacts with cationic and anionic species and enhances the absorption of radical species at 310 nm.