Enhanced thermal conductivity and wear resistance of polytetrafluoroethylene composites through boron nitride and zinc oxide hybrid fillers

Abstract

ABSTRACTIn this study, the thermal conductivity and wear resistance of the polytetrafluoroethylene (PTFE)/boron nitride (BN), PTFE/zinc oxide (ZnO), PTFE/tetra‐needle‐shaped zinc oxide whiskers (T‐ZnO), and PTFE/hybrid filler composites were investigated. Moreover, hot‐press molding was used to prepare the composites, and scanning electron microscopy was used to observe the morphology of the fillers and the friction interface of the composites. The results show that continuous thermally conductive paths could be formed in the PTFE/hybrid fillers (T‐ZnO and BN) composites so that the thermal conductivity of the PTFE was improved through addition of the hybrid fillers. Meanwhile, the synergistic effects of the hybrid fillers were useful for reducing the wear rate of the composites. In addition, for the pure PTFE, abrasive and adhesive wear was found. Compared to the worn surface of the pure PTFE, the worn surface of the PTFE composites filled with ZnO, T‐ZnO, BN, and hybrid fillers presented much smoother surfaces, and slighter ploughing occurred. Therefore, the hybrid fillers improved not only the thermal conductivity but also the wear resistance of the PTFE composites. The data obtained in this study contributed to the construction of a technical foundation for the preparation of composites with a high thermal conductivity and wear resistance. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42302.