MONTE-CARLO SIMULATION OF CHAIN-LENGTH DISTRIBUTION IN RADICAL POLYMERIZATION WITH TRANSFER-REACTION

In this paper, the basic principle and a Monte Carlo method are descri bed for numerically simulating the chain-length distribution in radica l polymerization with transfer reaction to monomer. The agreement betw een the simulated and analytical results shows that our algorithm is s uitable for systems with transfer reaction. With the simulation algori thm, we confirm that transfer reaction has a similar effect as disprop ortionation on the molecular weight distribution in radical polymeriza tion with continuous initiation. In the pulsed laser (PL) initiated ra dical polymerization with transfer reaction, the 'waves' on the chain- length distribution profile become weaker as the ratio of transfer rea ction rate constant, k(tr), to the propagation rate constant, k(p), is increased in the case with either combination-type or disproportionat ion-type termination. Moreover, it seems that the combination terminat ion has a broadening effect on the waves. Therefore, k(p) can also be determined by precisely locating the inflection point L(0) on the chai n-length distribution profile for radical polymerization with transfer reaction, unless k(tr) is large enough to smear out the waves on the chain-length distribution.