INFLUENCE OF AN AQUEOUS ACETONE MEDIUM ON THE THERMAL-BEHAVIOR OF SOLVENT TREATED POLY(ETHYLENE-TEREPHTHALATE)

When amorphous PET filaments are treated in acetone-water mixtures under controlled conditions, they retain amorphous properties. The T//g's and T//c's are lowered well below the usual values and at the same time the structure becomes swollen. Ageing the treated polymer freed from acetone results in a reversible process that gives transition values close to the values for the untreated sample; but the polymeric phase remains swollen. A combined action of primary and secondary plasticizers is proposed in this paper.