LIQUID-INDUCED CRYSTALLIZATION OF POLY(ETHYLENE TEREPHTHALATE)

Amorphous unoriented poly(ethylene terephthalate) was crystallized at 25°C by various organic liquids. The crystalliznity induced in the amorphous polymer was measured by differential scanning calorimetry and infrared spectroscopy. The ability of liquids to interact with and induced crystallinity in the amorphous polymer was classified on the basis of their solubility parameters. Measurements of the density of liquid‐crystallized 0.8‐mil films of poly(ethylene terephthalate) indicated the presence of extensive internal voids in the semicrystalline polymer matrix. Comparison of differential scanning calorimetric thermograms and infared spectra of heat‐crystalized and liquid‐crystallized polymer indicated significant differences in the polymer morphologies induced by the two crystallization processes. Copyright © 1969 John Wiley & Sons, Inc.