【摘要】 采用热模压工艺制备玻璃纤维(GF)改性热塑性聚酰亚胺(TPI)复合材料,使用3种不同的温度对复合材料进行退火热处理,考察了各材料体系热处理前后在高温环境中短时间及稳定的高温弯曲性能.探讨了材料在高温中的失效机理,发现热处理能消除材料在加工成型过程中产生的应力,使材料避免进入高温环境中短时间强度下降的情况,明显提高了材料的稳定高温弯曲性能,并大幅降低了材料的线膨胀系数.更多还原

【Abstract】 Glass fiber reinforced thermoplastic polyimide composites(TPI-GF) were prepared by thermo-molding process with three different temperatures chosen for the treatment of composites.Then the bending strength and modulus at elevated temperatures were measured before and after the treatment.The mechanism of damage was analyzed at elevated temperatures.It was found that heat treatment could alleviate the thermo-stress generated in the molding process,and heat treatment could avoid decreasing strength of composites in short time,modify the high temperature bending strength of TPI-GF composite,and reduce the coefficient of thermal expansion.更多还原