On the Viscosity of Irradiated Polymers. III. Effect of Branching

Abstract

The intrinsic viscosity of an irradiated polymetric substance is calculated with inclusion of the effect of branching. The contribution of a branched polymer to the intrinsic viscosity is evaluated according to Debye-Bueche’s theory with some modifications. The distribution of molecular size and crosslink unit is obtained through an extention of the Saito’s theory. Our results agree with experiment fairly well. The essential reason for the large discrepancy between Saito’s calculation and experiment is shown to be his neglect of branching.