导热结构对聚对苯二甲酸乙二醇酯非等温结晶行为的影响

Effect of thermal conductive structure on non-isothermal crystallization behavior of polyethylene terephthalate

针对聚对苯二甲酸乙二醇酯(PET)中的导热结构会影响纤维材料加工成形、纺织品加工过程以及纤维性能的问题,通过熔融共混法分别制备得到含有碳纳米管、石墨烯的PET复合材料,借助差示扫描量热仪对PET的非等温结晶动力学进行研究。结果表明:掺杂的碳纳米管、石墨烯在PET中起成核剂作用,其质量分数的增加对PET的结晶温度、结晶速率及结晶度具有促进作用;由Kissinger方程计算得到的纯PET和掺杂碳纳米管、石墨烯的PET复合材料的结晶活化能分别为-95.23、-160.27和-176.79 kJ/mol,结晶活化能的绝对值增加促进大分子分子链运动而使结晶过程放热加快;碳纳米管、石墨烯对PET的结晶速率、成核具有促进作用,其中石墨烯的二维片状导热结构对PET的结晶更有利。

The thermal conductive structure in polyethylene terephthalate will affect the processability of fiber materials and textiles,and various properties of the fiber.Polyethylene terephthalate(PET)composite containing carbon nanotubes(CNTs)and graphene(GR)was prepared by fusion mixing,and the non-isothermal crystallization kinetics of PET was studied by differential scanning calorimetry.The results show that doped carbon nanotubes and graphene act as nucleators in PET,and the increase in their mass fraction promotes the crystallization temperature,crystallization rate and crystallinity.The crystalline activation energies of pure PET,PETs doped with carbon nanotubes and graphene were-95.23、-160.27 and-176.79 kJ/mol,respectively,calculated using Kissinger method.The increase of the absolute value of crystallization activation energy promotes the movement of macromolecule chain and accelerates the exothermic process of crystallization.The results show that CNTs and GR promote the crystallization rate and nucleation of PET,and the 2-D sheet thermal conductivity of graphene favors PET crystallization.