几种改性剂对多孔聚酰亚胺含油性能和摩擦性能的影响

Effects of several modifiers on oil-bearing and tribological properties of porous polyimides

为探索多孔聚酰亚胺(PI)材料含油性能及摩擦性能的增强改进方法,采用介孔碳、石墨烯和稀土为改性剂制备多孔PI材料。研究了不同改性剂对材料的含油性能、摩擦性能和力学性能的影响。实验结果表明,介孔碳可大幅提升多孔PI的含油率,相比纯PI,介孔碳含量2wt%时的含油率提高了55.6%,但材料的摩擦系数有增大的趋势,力学性能也明显下降;少量的石墨烯可以提高多孔PI的含油性能和摩擦性能,但随着石墨烯含量的增加,多孔PI的含油摩擦系数快速增加,且冲击强度大幅降低;稀土极大改善了多孔PI的含油摩擦性能,随着稀土含量从0wt%增至5wt%,摩擦系数从0.05下降到0.026,超过5wt%后出现拐点,但所有试样含油摩擦系数均低于纯PI,且含油率呈上升趋势。相比介孔碳和石墨烯,稀土改性多孔PI的力学性能没有出现大幅降低的情况,对多孔PI综合性能的增强效果最优。

In order to explore the enhancement and improvement of porous polyimide(PI)material’s oil content and tribological properties,PI materials were prepared by using mesoporous carbon,graphene and rare earth as modifiers,respectively.The effects of different modifiers on the oil content property,tribological property and mechanical property of the materials were studied.The experimental results show that mesoporous carbon can greatly increase the oil content of porous PI.Compared with pure PI,the oil content of 2wt%mesoporous carbon increases by 55.6%,but the friction coefficient tends to increase,the mechanical property decreases obviously;a small amount of graphene can improve the oil content and frictional properties of porous PI,but with the increase of graphene content,the oil content friction coefficient of porous PI increases rapidly,and the impact strength decreases significantly;rare earth has greatly improved the oil content friction properties of porous PI.As the rare earth content increases from 0wt%to 5wt%,the friction coefficient decreases from 0.05 to 0.026.There is an inflection point after 5wt%.However,the oil friction coefficients of all samples are lower than the pure PI,and the oil content rate goes up.The mechanical property of rare earth modified porous PI doesn’t decrease significantly compared with mesoporous carbon and graphene,which shows the best enhancement effect on the comperhensive per-formance of porous PI.