石墨烯对聚四氟乙烯导热和摩擦磨损性能的影响

Effects of Graphene on Thermal Conductivity,Friction and Wear Properties of PTFE

针对聚四氟乙烯(PTFE)导热性能和耐磨损性能较差的问题,将石墨烯经过氧化氢预处理后,再用硅烷偶联剂KH550对其进行表面改性,然后采用冷压烧结法制备了PTFE/石墨烯复合材料,研究了不同用量下改性和未改性石墨烯对复合材料电性能、导热性能和摩擦磨损性能的影响。结果表明,随着石墨烯用量增加,复合材料的体积电阻率逐渐下降,但在石墨烯质量分数为0%~2%时,复合材料体积电阻率基本处于同一数量级,仍为绝缘材料;当石墨烯质量分数由0%增加至2%时,复合材料的导热系数明显提高,磨损量明显降低,而摩擦系数先升高后降低,但变化幅度较小。与未改性石墨烯相比,KH550改性石墨烯填充的复合材料具有更高的导热性能和摩擦磨损性能。

Aiming at the problem of polytetrafluoroethylene(PTFE)has lower thermal conductivity and wear resistance,using hydrogen peroxide to treat graphene and then modifying the surface of the pre-treated graphene by using KH550,PTFE/graphene composites were prepared by cold pressing sintering,the influences of modified and unmodified graphene under different contents on the electric,thermal conductivity,friction and wear properties of the composites were studied.The results show that,with the increase of the graphene content,the volume resistivity of the composite decreases,but when the mass fraction of graphene is0%-2%,the composites have the same order of volume resistivity and are still insulated material.When the mass fraction of graphene increases from0%to2%,the thermal conductivity of the composite increases and the wear loss decreases obviously,the friction coefficient first increases and then decreases,the change is little.Compared with the unmodified graphene,the KH550modified graphene filled composite has higher thermal conductivity,friction and wear properties.