SynopsisThe application of corresponding state principles to describe the properties of polymers is implicit in many of the fundamental studies of polymeric behavior. The seminal works of Prigogine, Hildebrand, Eyring, Flory, Gibhs, and DiMarzio in which multidimensional lattice representations and refined statistical mechanical approaches have been used are the basis for much of today's understanding of the thermodynamic behavior of polymers and their solutions. In this work the lattice energy of a polymer is defined in terms of reduced molecular parameters, and it is assumed that all polymers with the same functional form for their lattice energies will be in corresponding states. A reduced second order transition temperature is defined relative to a characteristic temperature T' = s~*/Zko*c, where the molecular parameters refer to the properties of the repeating segments of the polymer chain. Equations are derived that express the effects of molecular weight, plasticization, degree of crosslinking, and copolymerimtion on the second order (i.e., glass) transition temperature. In their limits, the equations are shown to reduce in form to equations derivable from free volume theory. They are also used to analyze succttssfully a variety of glass transition temperature data available in the Literature on homogeneous uncrosslinked and crosslinked polymers, plasticized polymers, and random copolymers.
The glass transition temperature, dynamic shear moduli, and bulk viscosities of Phenoxy PKHH (a thermoplastic polymer made from bisphenol‐A and epichlorohydrin) filled with glass beads and Attapulgite clay were investigated. The glass temperature of the polymer increased with increasing filler concentration and with increasing specific surface area of the filler. The data were interpreted by assuming that interactions between filler particles and the polymer matrix reduce molecular mobility and flexibility of the polymer chains in the vicinity of the interfaces. From the measured moduli and the viscosities of the filled and unfilled materials, the modulus reinforcement ratio in the glassy state and the relative viscosity in the viscous state were obtained as functions of the filler type and concentration. The relative modulus for the glass bead composite system follows the Kerner equation, while the clay‐filled systems exhibit slightly greater reinforcement. The relative viscosities are strongly temperature dependent and do not follow conventional viscosity predictions for suspensions. It is suggested that the filler has a twofold effect on the viscosity of the composite materials; one is due to its mechanical presence and the other is due to modifications of part of the polymer matrix caused by interaction. Using the WLF equation to express all modifications of the matrix, one can isolate a purely mechanical contribution to the viscosity reinforcement. This mechanical part is approximately bounded by the theoretical predictions of Kerner,32 Mooney, 36 and Brodnyan,41 for suspension viscosities.
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