微乳液中单分散银纳米颗粒的制备及抗磨性能

采用水/液体石蜡/Span 80-Tween 80/正丁醇微乳液体系, 制备了具有良好单分散性的Ag纳米颗粒. 通过X射线粉末衍射仪、透射电子显微镜、傅立叶变换红外光谱仪和热分析仪表征了Ag纳米颗粒的结构、形貌、粒径大小及分布、表面键合性质和热性能. 结果表明, 所制备的Ag纳米颗粒具有立方晶型结构, m(Span 80)∶m(Tween 80)=7∶3时, 粒径分布呈单分散性, 平均粒径约为6 nm. 在四球长时抗磨损试验机上考察了分散于液体石蜡中Ag纳米颗粒的抗磨性能. 实验结果表明, Ag纳米颗粒具有良好的抗磨性, 且能显著提高基础油的承载能力.

Preparation and Antiwear Property of Monodisperse Silver Nanoparticles in Microemulsion

Monodisperse Ag nanoparticles were prepared in quaternary W/O microemulsions containing Span 80-Tween 80, liquid paraffin and 1-butanol. It was found that mass ration of Span 80 and Tween 80 had an obvious effect on the morphology and size distribution of the Ag nanoparticles. Morphologies, structure and thermal properties of the silver nanoparticles were characterized by means of X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared (FT-IR), thermogravimetry (TG) and differential thermal analysis (DTA). The results show that the Ag nanoparticles have cube crystal structure; exhibit uniform size distribution and have an average size of 6 nm at the mass ratio of Span 80∶Tween 80=7∶3; and are coated with long chain fatty acid through carboxyl. H2O and 1-butanol in microemulsions were removed through vacuum distillation, and Ag nanoparticles were dispersed stably in liquid paraffin. The tribological properties of liquid paraffin containing Ag nanoparticles were evaluated on a four-ball test machine. Results showed that the Ag nanoparticles in liquid paraffin exhibited good antiwear property and could improve load carrying capacity of base oil remarkably.