摘要
基于聚酯的反应性共混原理,以聚对苯二甲酸乙二醇酯(PET)和聚对苯二甲酸丁二醇酯(PBT)为原料,醋酸锌(Zn Ac)为酯交换催化剂,利用双螺杆挤出机共混制备了共混产物PBT/PET嵌段型低熔点聚酯,研究了PET/PBT共混产物的制备工艺、结构、性能及其结晶动力学。结果表明:酯交换催化剂Zn Ac的添加对共混法制备低熔点聚酯具有重要作用,且当PET∶PBT的共混质量比为25∶75,Zn Ac添加质量分数为0.2%,在275℃下熔融共混3 min,可获得熔点为210.1℃的低熔点聚酯;利用Jeziorny法分析得到了其Avrami指数大于3,表明共混产物成核机理为异相成核,呈球晶三维生长方式,利用莫志深法分析表明共混产物在单位时间内要达到一定的结晶度需要更快的降温速率。
A low-melting point block polyester of polybutylene terephthalate/polyethylene terephthalate （PBT/PET） blend was prepared on a twin-screw extruder by using PET and PBT as raw materials and zinc acetate （ZnAc） as a transesterification catalyst based on polyester reactive blending principle. The preparation process, structure, properties and crystallization kinetics of PET/PBT blend were studied. The result showed that the incorporation of a transesterifieation catalyst, ZnAc, played an important role in the preparation of low-melting point polyester by blending process; and the low-melting point polyester could be obtained with the melting point of 210.1 ℃ by melt blending for 3 rain at 275 ℃ when the PET/PBT mass ratio was 25 ： 75 and the mass fraction of ZnAe was 0.2% ; an Avrami constant of the blend above 3 was observed by Jeziorny method, which indicated that the nucleation of the blend system was a kind of heterogeneous nucleation with three-dimensional spherulite growth. Mo analysis showed that a higher cooling rate was required when it became more difficult for the blend system to achieve a higher crystallinity in a unit time.
出处
《合成纤维工业》
CAS
2015年第6期29-34,共6页
China Synthetic Fiber Industry
基金
中央高校基本科研资助项目(2232013D3-17)
