| Nanomaterials, often referred as research forward field of materials science, have widely applied foreground because of their special physical and chemical properties. The dispersion capacity and stability of nanoparticles in water or oil-soluble media is one of the key technologies before nanomaterials could be applied, and is also a difficult problem to be urgently resolved. To resolve the above problems, the mechanism and dispersion behavior of dispersivity and dispersion stability of nanoparticles in nonaqueous medium were clarified, and the measures improving the above-mentioned performance were brought forward. The oil-soluble organic salts(including naphthenate, alkylsalicylate, saturated or unsaturated carboxylate), and five types of hyper-dispersion stabilizer( respectively possessing the anchoring groups end of oil-soluble polymeric chain, amino, carboxyl, amino-carboxyl, hydroxyl-carboxyl, isocyanato-)as well as hyper-dispersion stabilizer having post-reaction characteristic were successfully synthesized according to design performance. Sixty one kinds of nano-dispersion systems, including sulfide and soft metal of single-component, double-component, tri-component, tetra-component and five-component, were in-situ synthesized in oil-soluble medium, containing hyper-dispersion stabilizer self-made, by reacting oil-soluble organic salts with H2S, diamine hydrate, pyrogallic acid. Hyper-dispersion stabilizers possessing past-reaction characteristic have not only superior dispersive ability and stability characteristics, also product nanoparticles by its post-reaction with H2S or reducing agent. The remarkable characteristic of nanoparticle in-situ synthesizing in paraffin liquid, synthetic base oils and rapeseed oils is which can synchronously bring to success in a single system for the growth of particles, granularity control, agglomeration control, high degree dispersion and long lasting stability. To compare with existing methods, for example preparing nanoparticles in aqueous medium containing water-soluble organic compounds before dispersing nanoparticle in oil-soluble, in-situ synthesis method of nanoparticles can not only improve the dispersion and stability of nanoparticles in dispersion medium, predigest operating steps, but also remarkably reduce production costs. Furthermore, this method carriesthrough in room temperature and has no use for additional solvent, and the dispersion medium can be selected according to needs, for instance liquid paraffin, mineral base oil, synthetic base oil, petroleum ether, ethyl acetate, toluene. The nanoparticles content in oil-soluble dispersion medium can be ensured according to practical requirement, and max could exceed 10 percent.The accelerated test used for evaluating the dispersivity and dispersion stability of nanoparticles in oil-soluble medium was carried through common speed centrifuge and high speed centrifuge. The results showed that none of all dispersion systems come into being delamination through 72 h uncontinuity(2 h period, 4~5 period per day) common speed centrifuge test, and a few appear delamination through 34 h high speed centrifuge test, but most don't through 56 h . Those give the fact that dispersion systems possess very good dispersion stability not only in the common speed centrifugal field but also in high speed centrifuge field, and it could meet the need that the dispersion systems are long deposited in gravity field. The diameter, diameter distribution and conglomeration behavior of nanoparticles in dispersion medium was observed through freeze-etching replication transmission electron microscopy (ERTEM) technique and laser scattering methods. The results indicated that the nanoparticles scattering in medium, shape sphericity without agglomeration, the bareness diameter were 5~40 nanometer, the size of nanoparticles were uniformity. Their tribological properties of single or multi-component nano-dispersion systems as lubricating additives were evaluated with four-ball tribo-tester and ring block tribo-t...
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