钛系聚对苯二甲酸乙二醇酯的增黏行为及其性能

Thickening behaviour and performance of titanium-based polyethylene terephthalate

为了拓宽钛系聚对苯二甲酸乙二醇酯(PET)在聚酯工业丝领域的应用,通过超高效聚合物色谱-多角度激光光散射联用法研究其在不同温度下的增黏行为,建立增黏温度与钛系PET分子质量及其分布的关系,并利用紫外-可见分光光度计和差示扫描量热仪研究增黏PET的色相和热性能。结果表明:钛系PET分子质量随增黏温度的升高而升高,且色相受温度影响明显;增黏所需时间随温度升高而下降,270℃反应20 min的钛系PET重均分子量与220℃反应10 h时的相当,分子质量升高导致聚酯结晶性能和熔点下降;增黏温度超过熔点后,分子质量分布随温度升高而变窄,且分子质量可达到聚酯工业丝要求,高分子质量窄分布钛系聚酯的研究对其在工业丝领域的应用具有重要意义。

To extend the application of titanium-based polyethylene terephthalate(PET)in the manufacturing industrial polyester yarns,advanced polymer chromatography together with multi-angle laser light scattering was employed to research the thickening behaviour under various temperatures.A relationship between polycondensation temperature and molecular weight and its distribution of titanium-based PET were established.UV-Vis spectrophotometer and differential scanning calorimeter were used to study PET coloration with its thermal properties.The results indicate that molecular weight of the titanium-based PET increases as the polycondensation temperatures increase,and its coloration is obviously affected by the temperature.The required time for viscosity increasing decreases as the temperatures rise.The weight-average molecular weight for titanium-based PET obtained at 270℃for 20 min reaction time is similar to that obtained at 220℃for 10 h reaction time.It is shown that the elevated molecular weight leads to a decrease of PET crystalline performance and melt temperature.The molecular weight distribution becomes narrower when polycondensation temperature exceeds the melting temperature,and the molecular weight meets the requirements for industrial polyester yarns.The study on high molecular weight with narrow molecular weight distribution provides useful reference for making industrial polyester yarns.