Abstract:The chemical reaction characterization and rheological property of novel polyimide for 420℃ applica ̄
tion were analyzed. The influence of processing parameters on the properties of composites were also investigated.The
inner quality of composite was evaluated by ultrasonic C-scanꎬ microscopic analysis. Meanwhile the relationship be ̄
tween void contents and ultrasonic absorption ratio was discussed to determine the ultrasonic inspect parameter. Re ̄
sults showed that the resin and void contents could be effectively controlled by applying the pressure step by step. The
ultrasonic inspect could be carried out by probe of 5 MHz and gain of 15 dB to evaluate the quality of composite with
thickness of 2 to 3 mm. The polyimide composite prepared in this work exhibits excellent high ̄temperature mechanical
properties at 420℃ꎮ