Study On Preparation, Structure And Performance Of Novel NanoG/BMI Antifriction Composites

Because of their excellent characteristics, the novel resin-matrix antifriction composites have gotten much wider application as diversified antifriction accessories instead of the metal material or substitutes in the mechanical engineering. At present, conventional antifriction composites that are prepared with graphite tiny powder or cooperated with M0S2 for solid lubricants and resistant heat- resin have promising antifriction performance, only when the lubricant's content is as high as 20%wt or even higher. However, this high percentage of lubricant results in the decline in the mechanical performance of antifriction composites. This paper firstly puts forward the preparation method of novel antifriction nano-composites with graphite nano-sheets (NanoG) as lubricant, heat-resistant bismaleimide (BMI )for composite's matrix. The experimental results showed that the antifriction nano-composites with the loading of 3%-5% NaonG weight have the same antifriction performance as the regular antifriction composites with the loading of 20% graphite powder weight, but their mechanical performances much exceed that of the antifriction composite with graphite powder, and also exceed that of BMI polymer in many aspects.In the paper, the novel mode of "stirring and ultrasonic treatment" and "stirring, ultrasonic and wearable particulate treatment" intensified powdering was put forwards, and graphite nanosheets was modified with hexadecane trimethyl ammonium bromide and stearic acid to improve the NanoG's dispersion in the antifriction composite and reduce the NanoG's agglomeration. The optimal experimental conditions of NanoG's preparation and modification were obtained. However, the experimental results showed that although NanoG's modification effects were not satisfying, but the antifriction nano-composites with modified NanoG still have better antifriction performance than that of composites with unmodified NanoG.In addition, NanoG's layer structure and its structure in the antifriction composites, abrasion and friction mechanism and kinetic of NanoG/BMI curing reactions were investigated by means of modern analytic means, and its heat-resistant and mechanical performances were also studied. Based on the above studies, the results arrived at the following conclusions: the bigger the granularity of NaonG was, the better the lubrication...