Abstract: This paper dealt with the kinetics of radical polymerization initiated by pulsed laser in the absence of chain transfer reaction. The rigorous expressions of the number-and weight average degrees of polymerization for resulting polymer were derived. In the meantime, the normalized molecular weight-distribution functions for chain radicals, terminated species and total polymer were obtained respectively. Numerical calculation shows that the values of various molecular parameters, such as number-and weight- average molecular weights and polydispersity index, periodically vibrate between maxima and minima, and the amplitude of vibration decreases with increasing monomer conversion. The molecular weight distribution curves consist of some characteristic peaks, and the number of peaks increases with the decreasing of concentration of the primary radicals formed at the beginning per laser pulse. Comparing with disproportionation termination, combination termination leads to a narrower molecular weight distribution of resultant polymer.

Key words: Radical polymerization, Laser pulse, Kinetics, Molecular weight distribution