Liquid‐induced crystallization of poly(ethylene terephthalate)

Abstract

synopsisAmorphous unoriented poly(ethy1ene terephthalate) was crystallized a t 25°C by various organic liquids. The crystallinity induced in the amorphous polymer was measured by differential scanning calorimetry and infrared spectroscopy. The ability of liquids to interact with and induce crystallinity in the amorphous polymer was classified on the basis of their solubility parameters. Measurements of the density of liquidcrystallized 0.8-mil films of poly(ethy1ene terephthalate) indicated the presence of extensive internal voids in the semicrystalline polymer matrix. Comparison of differential scanning calorimetric thermograms and infrared spectra of heatccrystallized and liquidCrystallized polymer indicated significant differences in the polymer morphologies induced by the two crystallization processes.

Novel copolyesters containing naphthalene structure III. Copolyesters prepared from 2,6‐dimethyl naphthalate, ethylene glycol, and 2,2‐dialkyl‐1,3‐propanediols

“…Glass transition temperature ( T g ) decreases with increasing the content of the comonomer and length of the alkyl side chain. Similar multiple melting peak behavior has been observed by others20–22 and interpreted on the basis of distributions of crystallite sizes or perfection induced by thermal treatments. As can be seen, the temperature difference occurring between the higher melting peak ( T m H ) and lower melting peak ( T m L ) decreases with increasing content of the comonomer and length of the alkyl side chain.…”

The Effect of Crystallinity on the Vapor-Phase Sorption of Acetone in Oriented Poly(ethylene terephthalate)

“…The results indicate the scouring in C('I, induced a considerable amount of crystallinity as opposed to the result of Lawton and ~'ates [10]. This was probably due to possible traces of C('I, remaining in the polymer which could induce crystallinity during the drying at 75&dquo;(B Acetone sorption is not seen to alter crystallinity considerably except in the case of the unscoured sample, in which case, the increase in crystallinity was the same as that induced by scouring in C('Ii.…”

Processable Rylene Diimide Dyes up to 4 nm in Length: Synthesis and STM Visualization

“…Thus, those solvents being capable of strong interaction with a given polymer may be expected to induce the crystallization. Typically, some dissolution in fact will occur at the interface between the pure solvent and polymer surface due to a large concentration gradient 4…”