Orientation studies of poly(ethylene terephthalate)

摘要: This paper discusses the results of a detailed study relationships between molecular orientation, physical properties, and weight polyethylene terephthalate (PET), their dependence on orientation variables. The range samples used in this included average weights, Mw, 29,000 65,000 which correspond to inherent viscosities, I.V., from 0.5 0.9. temperatures investigated were 80 120°C. extent ordering imparted by process was studied birefringence, density, light scattering, depolarized intensity techniques. show that degree properties are strongly dependent strain rate, extension ratio, weight, temperature. mechanical transport PET directly related as measured birefringence. It is found at comparable level also whereas independent weight. varies according stretch shown for same ratio speed, birefringence decreases with increasing scattering indicate biaxial can lead strain-induced crystallization. amount form crystalline structures rate