石英纤维/聚酰亚胺复合材料的制备与性能

采用DSC、TG、FTIR和流变仪对KH-370聚酰亚胺树脂的化学反应特性和流变性能进行了表征。以QWB200石英纤维为增强体，采用热压成型工艺制备了QWB200/KH-370复合材料。研究了加压温度、压力大小、固化温度等不同工艺参数对QWB200/KH-370复合材料力学性能的影响，在此基础上确定了复合材料的成型工艺制度。考察了QWB200/KH-370复合材料400℃高温下的力学强度及宽频范围内的介电性能。结果表明，制备QWB200/KH-370复合材料的最佳工艺参数为:加压温度290~310℃，压力范围3.0~4.0 MPa，固化温度380℃。所得QWB200/KH-370复合材料具有良好的力学性能，400℃下力学强度保持率高于58%，表现出良好的耐热性能；而且在1~18 GHz的宽频范围内具有稳定的介电常数和介电损耗。 

Preparation and performance of quartz fiber/polyimide composites

The chemical reaction characterization and rheological property of KH-370 polyimide resin were characterized by DSC, TG, FTIR and rheometer. The QWB200/KH-370 composite was prepared by hot pressing technology with QWB200 quartz fiber as reinforcement.The effects of different process parameters (pressing temperature, pressure, curing temperature) on the mechanical properties of QWB200/KH-370 composites were studied. On this basis, the molding process system of the composites was determined.The mechanical strength of the composite at 400℃ and the dielectric properties at broad frequency were also investigated. According to the results, the best process parameters for the preparation of QWB200/KH-370 composites are: pressing temperature of 290-310℃, pressure range of 3.0-4.0 MPa, curing temperature of 380℃. The prepared QWB200/KH-370 composites exhibit excellent mechanical properties at room temperature, and the retention rates of mechanical strength at 400℃ is above 58%, showing good heat resistance. The QWB200/KH-370 composites show stable dielectric constant and dielectric loss at broad frequency from 1 GHz to 18 GHz.