Orientation, Stress, and Density Distributions in Injection-Moulded AmorphousPolymers Determined by Optical Techniques

摘要

The quantification of the complete state of an injection moulded amorphouspolymer by measuring molecular orientation, residual stresses, and density distributions by optical techniques, is addressed. For this purpose the contribution of molecular orientation and residual stresses to birefringence is distinguished quantitatively, and an optical technique for density measurements is introduced. A collection of papers is presented. In order to be able to quantify orientation, stress, and density, the attention is focussed on four different items: (1) the stress optical behavior of the polymers in the entire temperature range of interest; (2) the thermomechanical history of the samples in quenching and injection moulding; (3) the entropy elastic and energy elastic contribution to birefringence; and (4) different experimental techniques, including a new technique to determine refractive index distributions.