Effect of Crystal Status Transformation on the Thermal Shrinkage Characteristics and Extensional Characteristics of Acetaldehyde Solvent-Induced Crystalization PET Film

Abstract

It was previously reported acetaldehyde-induced crystallization of PET film wherein the original unoriented film is dipped in acetaldehyde for 5 min to drastically enhance its crystallinity. It was conducted additional experiments and evaluated this crystallinity by infrared, X-ray analyses. We report here a type of T X (a so-called middle crystal status) that does not lead to complete thermal shrinkage proof. By the acetaldehyde-induced process, CH 2 -wagging at 1340cm -1 is activated. However, the degree that a carbonyl group and a benzene ring are packed on the same plane by this solvent processing is reduced. These results are related to the improvement of heat resistance after stretching at 80°C and the highly extensional characteristics at 20°C of this stretched film after placing in boiling water.