Micro-nano coupled capsules with "solid-liquid synergy and two-stage response" for high-temperature resistant self-lubricating polymer composites

Micro-nano coupled self-lubricating capsules with a double-layer core-shell structure (PI@OIL-F/HMCS) were developed to enhance the tribological performance of PPEK composites. The capsules exhibit excellent thermal stability, reducing the friction coefficient and wear rate by 88.14 % and 94.79 % at room temperature. At 300 °C, the composite maintains a low friction coefficient (0.05) and a wear rate of 9.6 × 10⁻¹ ⁶ m³ /(N·m). A solid-liquid synergy and two-stage response mechanism ensures continuous lubrication and film integrity under high temperature and load. This work offers a new strategy for designing heat-resistant self-lubricating materials and advances the development of high-performance polymer composites.