High-temperature resistance and wave-transmitting quartz-fibre/polyimide composite

Here, composite based on quartz fibre-reinforced fluoro-polyimide was fabricated using a hot press process, which was reported having well thermal and dielectric properties. The polyimide exhibited extremely high glass transition temperature (Tg) up to 471°C, and 5% weight loss temperature (T5) about 560°C both in nitrogen and air. Also, optimisation of processing parameters of composite was investigated. Moreover, the quartz fibre/polyimide composite possessed excellent high-temperature mechanical properties due to the high Tg. Importantly, the composite exhibited excellent dielectric performance. Especially, the dielectric constant values had remained basically unchanged of 3.43–3.46 at 400°C in the frequency range of 7–18 GHz, indicative of a remarkable wave-transmitting property. Besides, the transmission efficiency of the composite was up to 83% in the frequency range of 7 –18 GHz. This study can serve as a basis for rapid evaluation of the high heat resistance and waving-transmitting property polyimide composite in various application environments.