插线板用高抗冲阻燃耐热PET/PC合金的制备

Preparation of Flame Retardant PET/PC Alloy with High Impact and Heat Resistant for Plugboard

采用双螺杆挤出机熔融共混挤出制备了聚对苯二甲酸乙二酯/聚碳酸酯(PET/PC)合金。研究了PET和PC黏度对合金力学性能、耐热性能、阻燃性能的影响。结果表明,PC树脂的黏度不会影响PET的结晶行为,且PC树脂的黏度越大,合金的力学性能和耐热性能越好。中黏PET的结晶度高有利于提高合金的耐热性能,但是会降低合金的韧性。选用高黏PET和高黏PC的组合可以得到高韧性、高耐热的合金。酯交换抑制剂的加入可以抑制PET和PC之间的酯交换反应,使得合金的球压痕直径减小。但是过多的酯交换抑制剂会降低材料的韧性,当酯交换抑制剂添加量超过0.6份后,合金的悬臂梁缺口冲击强度降低至23kJ/m^2以下。加入少量的扩链剂可以提高合金的力学性能。在增容剂、阻燃剂等加工助剂一定的情况下,基体树脂选用高黏PET和高黏PC,并加入0.4份酯交换抑制剂、0.2份扩链剂,此时合金的综合性能最好,缺口冲击强度达到62kJ/m^2,球压痕直径为1.9mm,满足插线板的国家标准要求。

The polyethylene terephthalate/polycarbonate (PET/PC) alloy was prepared by melt blending,extruded by twin screw extruder. The effects of the viscosity of PET and PC on the mechanical properties,heat resistance and ame retardancy of the PET/PC alloy were studied. The results show that the viscosity of PC resin does not affect the crystal behavior of PET,and increased viscosity of PC can improve the mechanical properties and heat resistance of the the PET/PC alloy. High crystallinity of moderately bonded PET is bene cial to improve the heat resistance of the the PET/PC alloy,but reduces the toughness of the the PET/PC alloy. Choosing high viscosity PET and PC can get the PET/PC alloy with high toughness and heat resistance. The ad- dition of transesteri cation inhibitors can inhibit the transesteri cation reaction between PET and PC,reduce the ball indentation diameter of the PET/PC alloy. But too many transesteri cation inhibitors can signi cantly reduce the toughness of the alloy,when the dosage of transesteri cation inhibitor reaches 0.6 phr,the notched Izod impact strength of the alloy decreases to below 23 kJ/ m^2. The mechanical properties of the alloy can be improved by adding a small amount of chain extender. Under certain conditions of compatibilizer and ame retardant,chosing high viscous PET and high viscous PC as matrix resin,adding 0.4 phr of ester exchange inhibitor and 0.2 phr of chain extender,the comprehensive performance of the alloy is the best. The impact strength is 62 kJ/m^2, the ball indentation diameter is 1.9 mm. The alloy meets the national standard requirements of plugboard.