High‐Temperature Tribological Reinforcement and Dynamic Interfacial Behavior of PEEK Composites Enhanced by APTES ‐Functionalized Graphene Oxide: A Molecular Dynamics Investigation

ABSTRACT To address the challenges associated with the inherently high coefficient of friction (COF) of polyether ether ketone (PEEK) and the significant degradation of its mechanical and tribological properties under extreme high‐temperature conditions, this study employs molecular dynamics (MD) simulations to investigate the enhancement of high‐temperature performance in PEEK composites through the incorporation of (3‐Aminopropyl) triethoxysilane functionalized graphene oxide (APTES‐GO). The thermal, mechanical, and tribological response mechanisms are systematically investigated over a wide temperature range from 298 to 423 K. Results show that APTES‐GO significantly enhances the thermal stability and stiffness of the matrix through interfacial reinforcement, increasing the glass transition temperature by approximately 39.74 K. Notably, at 423 K, the Young's modulus of the composite remains at 3.07 GPa, representing an improvement of over 50% compared to pure PEEK. Friction simulations reveal that under high‐temperature sliding conditions at 423 K, the COF of APTES‐GO/PEEK decreases to 0.2331, significantly outperforming both pure PEEK (0.2778) and unmodified GO/PEEK (0.2529). Microscopic mechanism analysis confirms that APTES not only improves interfacial compatibility but also promotes the formation of a dense, dynamic hydrogen‐bonding network at the interface. During the process of friction, this network dynamically promoted molecular anchoring of PEEK chains, thereby effectively suppressing thermally induced plastic flow and interfacial slippage. Collectively, these results reveal the interfacial microscopic mechanisms by which functionalized fillers enhance frictional stability at elevated temperatures—offering fundamental theoretical insights for designing high‐performance polymer‐based sealing materials capable of withstanding extreme environments.