Linear Viscoelastic Properties of a Poly(arylene ether ketone) with Various Molecular Weights

Abstract

A new poly(arylene ether ketone) polymer (PAE) has been synthesized. This polymer was prepared from the reaction of 1, 3-bis(4-fluorobenzoyl)benzene with 2, 2-bis(4-hydroxyphenyl)propane. Dynamic rheological measurements were performed on a series of six PAE polymer melts with weight average molecular weight (Mw) ranging from 9, 600 to 113, 000 g/mole and the linear viscoelastic properties were characterized. These stiff polymers behave like thermorheological simple fluids. A WLF type of equation was found to be adequate to describe their temperature dependent properties within 100°K above the polymer glass transition temperatures, T_g's. In the regime where the chain entanglement effects predominate, the dependence of zero shear viscosity on the Mw, M%ôMw^B with β=5.13, was noted to be stronger than normally observed for polymers with flexible chains. The rate dependent viscosities for samples with different Mw can be superimposed to form a master curve by shifting along the reduced frequency axis. The shift factors are shown to be described by Graessley's theory based on molecular chain entanglements.