聚碳酸酯/聚对苯二甲酸丁二醇酯交替层状复合材料的制备和冲击性能提升

Preparation of Polycarbonate/Polybutylene Terephthalate Alternating Multilayered Composites and Improvement of Impact Properties

如何调控酯交换反应程度是改善聚碳酸酯/聚对苯二甲酸丁二醇酯(PC/PBT)共混物冲击强度的关键。文中采用酯交换抑制剂焦磷酸二氢二钠(DPPH)和多层挤出加工技术制备了具有多层结构的PC/PBT-DPPH交替层状复合材料,对比分析了多层结构和酯交换抑制剂的加入对PC/PBT共混物力学性能的影响。结果表明,相较于传统PC/PBT-DPPH共混物,交替层状复合材料的缺口冲击强度从3.6kJ/m^(2)增加到19.3kJ/m^(2),同时拉伸强度保持在53.2MPa。与传统共混相比,多层挤出过程中,PC与PBT的酯交换反应主要发生在层界面处,DPPH的加入使层界面的酯交换反应得到很好的控制,层界面由“刚硬”转变为“柔软”,从而显著提高冲击性能。

How to control the degree of transesterification reaction is the key to improving the impact strength of polycarbonate(PC)/polybutylene terephthalate(PBT)blends.In this study,PC/PBT-DPPH alternating multilayered composites with multilayer structure were prepared by transesterification inhibitor disodium dihydrogen pyrophosphate(DPPH)and multilayer extrusion processing technology,and the effects of multilayer structure and transesterification inhibitor addition on the mechanical properties of PC/PBT blends were compared.The experimental results show that compared with the traditional PC/PBT-DPPH blends,the notched impact strength of the alternating multilayered composites increases from 3.6 kJ/m^(2) to 19.3 kJ/m^(2),while the tensile yield strength remains at 53.2 MPa.Compared with traditional blending,the transesterification reaction of PC and PBT in the multilayer extrusion process mainly occurs at the layer interface,and the addition of DPPH makes the transesterification reaction of the layer interface well controlled,so that the layer interface changes from"hard"to"soft",thereby significantly improving the impact performance.