Structural changes in glassy poly(ethylene terephthalate)

Abstract Structuralchanges in glassy poly(ethylene terephtbalate) and their effects on its crystallization, melting, and various properties were studied. Quenched, annealed below Tg, crystallized, and drawn samples were studied using calorimetry, wide-and small-angle X-ray diffraction, mechanical spectroscopy, and stress-strain analysis. All results indicate some level of order in the glassy polymer which can be increased by annealing below Tg. This order still exists at tempertures above Tg and affects the properties of the polymer.