On the Damped Debye Lattice Model for Modified Amorphous Polymeric Systems

Abstract

Abstract The steepness index (SI) of the stress relaxation master curves is shown to vary in a predictable way when the structure of the polymer is changed by the addition of fillers or by copolymerization, plasticization, or chemical substitution. The changes in SI can be associated with changes in the degree of inter-chain coupling produced by the various modifications. It is proposed that the peculiar differences in the value of SI between otherwise similar amorphous polymers, as PS and PMMA, may be related to certain thermal parameters, as is the case in the calculation of the Gruneisen constants.