含碳纳米管、石墨烯的PTFE基复合材料摩擦磨损性能

Friction and wear properties of PTFE composites containing CNT and graphene

对碳纳米管和石墨烯进行了表面羧基、氨基接枝改性,并制备了碳纳米管/聚四氟乙烯和石墨烯/聚四氟乙烯复合材料。利用表面官能团的供电性和聚四氟乙烯表面氟的强电负性的诱导效应,改善了纳米增强体在基体中的分散性,并实现了纳米增强体/基体界面的强化。复合材料摩擦磨损性能研究结果显示,两类碳系纳米增强体中,均为经过氨基化接枝改性者对复合材料摩擦磨损性能的改善效果最优,而未经改性的增强体最差。两种复合材料均为增强体含量为1%(质量分数)时磨损率最低。碳纳米管在PTFE基体中可有效承载,避免基体在载荷剪切下形成的微观撕裂,使得复合材料的磨损率明显降低,最大降幅为69.6%;石墨烯除具有承载功能外,还可以有效地形成转移膜,降低复合材料摩擦系数,复合材料磨损率的降幅更高达73.9%。

Modified the surface of CNT and graphene by grafting carboxyl group and amino group,and prepared CNT/PTFE composites and graphene/PTFE composites.Improved the dispersion of nano-reinforcements in PTFE matrix and enhanced the interface bonding via inductive effect between surface functional groups in nano-reinforcements and fluorine atom in PTFE surface.The friction and wear research results shows that grafting a-mino group in nano-reinforcements’surface improved composites’friction and wear properties best,and un-modified reinforcements presented worst properties.Composites of 1wt% reinforcements content showed the lest wear rate both CNT/PTFE composites and graphene/PTFE composites.CNT in PTFE matrix can effec-tively bear loads,avoid microscopic tearing resulted by shear force,so the wear rate of composites can reduce significantly,the largest decline was 69.6%,apart from bearing load,graphene can also form a lubricating film, reducing the friction coefficient and the wear rate of the composite,of which the wear rate felled as much as 73.9%.