The synthesis and study of metal powder stabilizer properties in lubrication compositions

Introduction. Modern manufacturing technologies of powder materials allow obtaining particles sized 0.1-0.5 |xm. Powders with such dispersion have a very high surface energy and, consequently, unique properties. Powders with a given size can be used as an additive to motor oil to form the surface film with high tribological properties. However, the widespread use of ultra-nanoscale powder materials as additives to motor oil limits sedimentation and aggregation of the particles. As a result, the dimensions of the metal crystals increase to dozens of microns and their particles are then retained by oil filters of engines that leads to efficiency decrease and even to clogging oil-conducting channels and to setting the friction surfaces of the parts. The most technically competent solution for increasing sedimentation resistance of the lubricant composition is the use of chemical stabilizers forming the thinnest film at the surface of metal particles, which not only hinders particle aggregation, but also keeps them suspended for a long time. Materials and Methods. As stabilizers of dispersed metal powders in lubricant compositions, organic compounds of various classes are used. The analysis of several stabilizers of disperse metal powders is given in the paper and new compositions are proposed: apinezon MN, polyethylene glycol sebacate and commodity stabilizer apiezon L. The methods of stabilizers synthesis and examination of their activity are described. Results. The stabilization activity of the developed preparations was compared to the basic version: oleic acid. Addition of the ester of ethylene glycol sebacate had no stabilizing effect on the lubricant composition. The synthesized MN and Mg reagent apeizon L show stabilizing properties with respect to metallic powders of the lubricant composition, comparable with the properties of oleic acid. Discussion and Conclusion. Since apiezon greases are a mixture of hydrocarbons, their corrosivity is much lower than that of oleic acid, they can be recommended for practical use.