改性双马树脂/碳纤维复合材料体系耐湿热性能研究

Study on the hydrothermal properties of a modified bismaleimide resin/carbon fiber composite

对5428/T700复合材料的吸湿率、不同吸湿条件下的玻璃化转变温度及高温湿态力学性能进行了研究。结果表明,5428/T700体系具有较低的吸湿率,经70℃去离子水水煮72 h,吸湿率为0.5%,饱和吸湿率(水煮360 h)为0.8%。而且随着复合材料吸湿量的增加,其Tg下降缓慢;5428/T700复合材料在干态170℃下的弯曲性能和层间剪切性能保持率在70%以上,在湿态150℃下的弯曲性能和层间剪切性能保持率在50%以上;5428/T700复合材料在湿态150℃下的开孔压缩强度保持率在80%以上。

5428 resin was a high-toughness modified bismaleimide resin, which was developed in recent years. When it combined with the carbon fiber T700, the composite could meet the needs of high-properties and lowcost in the aeronautical field. Because the aeronautical materials were usually used in the hydrothermal condi- tions, it was necessary to conduct an investigation into the hydrothermal properties of the materials. In this paper, the hydrothermal properties of 5428/T700 composite was described, such as the moisture-absorption rate, the Tg under the condition of different moisture-absorption, and the mechanics performance under the hydrothermal conditions of 5428/T700 composite. The results meant that the 5428/T700 composite had low wetabsorption rate, that was 0.5% at infusing 72 h in deionized water at 70℃ and the saturated wet-absorption rate （infusing 360 h in deionized water at 70℃） was 0.8%, but the glass state temperature was slowly decreased with wet-absorption increased and the retention ratio of its mechanical properties such as flexural property and interlaminar shear strength in the condition at 170℃ and dry state was more than 70 % but its retention ratio in the condition at 150 ~ and wet state was also more than 50 % meantime the retention ratio of the openhole compression strength was more than 80%. Therefore, the 5428/T700 composite had good hydrothermalresistance ability.