滑石粉改性低熔点PBT结晶性能研究

Study on the crystallization of low melting point PBT modified by talcum powder

为提高低熔点聚对苯二甲酸丁二醇酯(PBT)的结晶性能,将滑石粉分散在1,4-丁二醇(BDO)中,与对苯二甲酸(PTA)、间苯二甲酸(IPA)和己二酸(AA)等进行共聚,得到改性低熔点PBT。利用差示扫描量热仪(DSC)研究了不同滑石粉加入量的低熔点PBT的非等温结晶性能,并采用Jeziorny方程及莫志深非等温结晶动力学方程对非等温结晶进行处理,结果表明:滑石粉改性可以显著促进低熔点PBT的结晶,结晶速率提高,表现在结晶温度和结晶活化能增大,半结晶时间缩短。动力学分析表明Jeziorny法虽然有一定的偏差,但能很好的分析结晶过程;莫志深方程适合描述低熔点PBT的非等温结晶过程,在达到相同结晶度时,加入滑石粉的低熔点PBT所需降温速率更小,可以缩短低熔点PBT后加工涂覆后的冷却固化时间。

To improve the crystallization properties of low melting point PBT,talcum powder which dispersed in 1,4-butanediol(BDO),terephalic acid(PTA),isophthal-icacid(IPA)and adipic acid(AA)are copolymerized to obtain modified low melting point PBT.The non-isothermal crystallization properties of low melting point PBT modified by talc were studied by differential scanning calorimetry(DSC).The kinetic data obtained were processed by Jeziorny equation and Mo's new non-isothermal crystallization equation.The results that modified by talc promotes the crystallization of low melting point PBT.The crystallization rate improves greatly,the crystallization temperature and crystallization activation energy increase,half-crystallization time is shortened.The kinetic analysis results show that although the Jeziorny method had some deviations in analyzing the whole crystallization process,it could be applied to analyze the main crystallization well.Mo's equation is suitable to describe the non-isothermal crystallization process of low melting point PBT,adding talc needs lower cooling rate when achieve the same relative crystallinity,it can shorten the cooling and solidification tiem after processing and coating of low melting point PBT.