| Summary: | 碩士 === 國立臺灣科技大學 === 纖維及高分子工程技術研究所 === 85 ===
In this study, the crystallization behavior of poly(ethylene terephthalate)/phosphorus-containing copolyester blends are investigated. The results of WAXD indicate that samples from hot press show lower crystalline while those from solution casting exhibit a higher crystallinity. The crystallinity of copolyester decreases with increasing phosphorus content. The result of the non-isothermal crystallization shows that the crystallization temperature of copolyester depresses with increasing phosphorus content. As a given phosphorus content, the crystallization temperature of the blend prepared from physical mixing is higher than that of copolyesters. The calculated result of Avrami index is about 2.5 for both PET and PET/P30 blends, implying that crystallization mechanism is related to the sporadic nucleation, the growth of spherulites and diffusion control processes. Blends with P30 content lower than 10% show that the overall rate of crystallization rises with increasing with P30 content, while that of samples with P30 content higher than 20% depressed with increasing P30 content. These results could be confirmed from POM experiment. However, no matter phosphorus linkage into the main chain or the side chain, the crystallization mechanism of copolymers is only influenced by the crystallization temperature and phosphorus content. PET-co-PEDDPs have higher decomposition temperature than those of PET-co-PEPPs. The products of PET-co-PEDDPs must have a better thermal stability than that of PET-co-PEPPs. As a given phosphorus content and crystallization temperature, the overall rate of crystallization of physical blends is faster than that copolyesters.
|
|---|
