Development of mechanical and thermal properties of PEEK composites by incorporating inorganic particles modified phosphates

Abstract This work aims to improve heat resistance and mechanical properties of PEEK composites by filling the modified phosphates with inorganic particles (Si3N4, AlN, Al2O3 and Cu2O) as reinforcements. The modified phosphate/PEEK composites were successfully prepared by pre-mixing and compression molding. The crystalline structures and compositions of modified phosphates and composites are characterized. Furthermore, the thermal and mechanical properties of composites were evaluated by thermal aging resistance at 350 °C for 24 h. The results show that all the four kinds of phosphate reinforcements can enhance the thermal aging resistance of phosphate/PEEK composites to varied extent. For the modified phosphate by Al2O3, its addition increases the 30% weight loss temperature (T30) by 55 °C. Moreover, the compressive strength exhibits a 105.6% enhancement, reaching 321.4 MPa from 156.3 MPa of the PEEK matrix. This work provides a valuable route to improve the thermal and mechanical properties of PEEK composites, which would have promise applications in heat-resistant and high-strength structural materials.