High-Temperature Superlubricity Microcapsules

Small. 2025 Dec;21(49):e08109. doi: 10.1002/smll.202508109. Epub 2025 Oct 19.

Abstract

Superlubricity, characterized by an ultra-low coefficient of friction (COF) below 0.01, is crucial for reducing energy losses in mechanical systems but remains challenging at high temperatures. This study designed a high-temperature-resistant solid-liquid coupled microcapsule containing perfluoropolyether (PFPE) and molybdenum disulfide (MoS2) encapsulated in silica (SiO2) to develop a self-lubricating composite material for high-temperature applications. By embedding these microcapsules into a polytetrafluoroethylene (PTFE) matrix, macroscopic superlubricity (minimum COF = 0.005) is achieved in atmospheric environments up to 200-250 °C. The excellent tribological performance is attributed to the synergistic effects of the stress-responsive release of trace lubricants, the decreased COF of the PTFE matrix at high temperatures, the low viscosity of PFPE oil reducing internal friction, and the formation of a boundary lubrication film by MoS2. This work provided a new strategy for enabling low-wear operation of polymer materials under extreme thermal conditions and holds significant implications for expanding the application boundaries of superlubricity technology.

Keywords: high temperature; microcapsule; superlubricity.