含短切碳纤维耐高温树脂基吸波复合材料的制备与研究

Preparation and Research of High Temperature Resistant Resin-based Wave-absorbing Composites Containing Chopped Carbon Fibers

制备了短切碳纤维(Csf)为吸波剂、聚酰亚胺树脂(PI)为基体、连续石英纤维(QF)为增强体的耐高温树脂基吸波复合材料,设计了多层Csf/QF/PI吸波材料并研究4~18 GHz频段范围内的常温与高温吸波性能,探讨了材料吸波性能随温度变化的原因,研究了短切碳纤维吸波剂对于QF/PI复合材料玻璃化转变温度(Tg)的影响。所制备的QF/PI复合材料DMA-Tg为319℃,经Csf改性后达340℃。在4~18GHz频段内,随着温度的升高(23℃~300℃),材料的反射率吸收峰强度先增大后减小,100℃~200℃时强度最大。

In this thesis,we fabricated the high-temperature resistant wave-absorbing composites by short carbon fiber(Csf)as absorber,polyimide(PI)as resin matrix and continuous quartz fiber(QF)as reinforcement.At the frequency range of 4~18 GHz,we studied microwave absorption properties of multi-layer absorber from normal to high temperatures.The causes for the variation of the absorbing properties with temperature are discussed.The effect of Csf absorbing agent on the Tg at high temperature of QF/PI composites was investigated.DMA-Tg of the composite material fabricated was 319°C which can be modified to 340°C with suitable addition of Csf.At 4~18 GHz band,the reflectance absorption peak intensity of the absorbing material increased and then decreased with increasing temperature(23°C~300°C),in which the peak intensity reached the maximum at 100°C~200°C.