Molecular Weight Distribution Generated on Initiation of Free Radical Polymerization by Sequence of Laser Pulses

Abstract

An investigation of molecular weight distributions (MWDs) resulting from initiation of free radical polymerization by an arbitrary sequence of short laser pulses has been undertaken. The analytical expressions have been derived to calculate MWDs for a polymerization scheme that contains reactions of chain initiation, propagation and termination by recombination or disproportionation. The MWDs produced by pulse-periodic irradiation have been calculated for a wide range of initiating pulses repetition rates (f = 0.05–100 Hz). The MWD dynamics in the act of polymerization and the influence of the duration of polymerization pseudostationary regime establishment upon the MWD have also been studied. The suitability of the derived expressions for describing the MWD generated by CW radiation before and after the establishment of polymerization quasi-stationary regime has been considered.