Stress relaxation in polyethylene crystallized by orientation

Abstract

Stress relaxation has been investigated in PE in the initial condition and after crystallization by orientation with various values of the extension ratio. The experimental data obtained have been generalized by means of the temperature-time analogy. Values of the effective activation energy have been calculated for the deformation of PE crystallized by orientation. The activation energies are shown to approximate to those found for the principal relaxation processes in HDPE determined by other independent methods.