Design of Novel POB/h-BN Co-Filled PTFE Composites with Enhanced Thermal–Mechanical Properties

Polytetrafluoroethylene (PTFE) is provided with excellent self-lubricating properties and corrosion resistance. However, the lower thermal resistance greatly limits its high-temperature applications. In present work, two types of fillers rigid organic polymers submicron-sized inorganic hexagonal boron nitride (h-BN) were added to PTFE matrix. The microstructure thermal–mechanical PTFE-based composites different filler or ratios comparatively investigated. results suggested that polyphenyl ester (POB)/h-BN co-filled exhibited compared polyimide (PI)/h-BN/PTFE materials at high temperature. optimal POB h-BN 25 wt.% 5 wt.%, respectively. Vicat softening temperature POB/5 PI/PTFE composite increased by 41.3% pure PTFE, which was due cross-linked reticulation structure regularly distributed pores higher crystallization degree. storage modulus from 51.99 MPa 685.76 260 °C reached 187.82 320 °C. uniform distribution anisotropic orientation flakes showed an obvious pinning effect, further improved stability POB/h-BN/PTFE composites.