Study on the Thermo-Oxidative Aging Mechanisms and Performance Evolution of Polyether Ether Ketone Materials

This paper investigates the thermo-oxidative aging behavior of three grades of polyether ether ketone (PEEK)—Victrex 450G, Zhongyan 550G, and Poke KVH200B—through systematic experimentation. The evolution of electrical insulation, mechanical, and thermal properties under prolonged aging was characterized and analyzed. Results indicate that aging induces molecular chain scission, reduction in molecular weight, formation of polar oxidative groups, and localized crosslinking, collectively leading to degradation in volume resistivity, dielectric performance, compressive strength, modulus, and thermal stability. Among the materials studied, KVH200B exhibits enhanced thermal aging resistance, with more stable glass transition and melting behavior. The correlation between microstructural changes and macroscopic property deterioration is elucidated, offering a theoretical basis and experimental data for lifetime prediction and performance optimization. These findings provide engineering insights into the application and reliability design of PEEK materials, particularly in high-demand environments such as nuclear power systems.