Plasticized PVC Reinforced with Cellulose Whiskers. I. Linear Viscoelastic Behavior Analyzed through the Quasi-Point Defect Theory

摘要

In a previous article, the processing of nanocomposite materials of plasticized poly(vinyl chloride) (pPVC) reinforced by cellulose crystalline whiskers was presented as well as preliminary dynamic mechanical measurements. The purpose of the present work is to evaluate the possible change of molecular dynamic of poly(vinyl chloride (PVC) at the interface with cellulose whiskers. Teh analysis, based on the quasipoint defect (qpd) theory for the anelastic deformation of amorphous polymer, confirms that PVC is heterogeneous. Thus, the matrix is described as a parallel assembly of phases with differnet plasticizer concentration (i.e., different glass transition temperature). It is shown that the whiskers do not lead to supplementary relaxation in te matrix, at least in the time-temperature window of the study, but, the satisfying modeling of the composite supports the assumption of a thin layer of immobilized pahse around the whiskers.