High-temperature resistance quartz-fabric/phthalonitrile composite with excellent waving-transmitting performance

This study reports the fabrication of quartz fabric reinforced phthalonitrile composite possessing good thermal and wave-transmitting properties. Phthalonitrile-terminated oligomer PN-SF curing behavior was investigated using differential scanning calorimetry (DSC) and dynamic rheological analysis (DRA), revealing a good processability pre-curing temperature of only 175°C. The thermoset exhibited the 5% loss temperature about 462°C, and after the temperature rising to 400°C and 400°C/2 h aging, the weight loss was only 10%, indicating that the resulting thermoset possessed outstanding thermal property. Moreover, the resulting thermosets possessed extremely high glass transition temperature (Tg) about 420°C. Besides, the quartz fabric/phthalonitrile composite possessed extremely excellent mechaical properties. Importantly, the transmission efficiencies can reach 87% at a certain frequency at the incident angle of 0°∼35°, indicating its well waving-transmitting performance. Meanwhile, the composite exhibited stable and relatively low dielectric constant and dielectric loss at the range of 12∼18 GHz. This study can serve as a basis for rapid evaluation of the high heat resistance and waving-transmitting phthalonitrile resin-based composite in various application environments.