Effect of conditions of synthesis on the molecular weight distribution of products of high temperature polycondensation

Abstract

Using F-2 polyarylate a study was made of the effect of medium-solvents-during high temperature polycondensation on molecular weight characteristics. It was found that when synthesis is carried out in α-chloronaphthalene M w, [ν] and polyarylate yield are somewhat higher than in the case of ditolylmethane. According to experimental results, branched macromolecules are formed in ditolylmethane, for which the average number of branching centres decreases with a reduction in the duration of synthesis. Analysis of curves of MWD according to results of fractionation shows that the polydispersion of polyarylates synthesized in α-chloronaphthalene approximately corresponds to the most probable MWD, while in ditolylmethane polydispersion also increases with an increase in branching. Possible causes of branching when using ditolylmethane as medium, were examined.