Synthesis And Performance Of Dispersants For Nano-copper Powder In Lubricant

The nanometer particles are metastable materials that lie between macroscopical materials and atom or molecules with the characteristics of little size effect, quantum measurement effect, suface effect and macroscopical quantum tunnel effect, etc., thus demonstrating some special properties. When mixed with the lubricating oil, the nanometer particles can improve lubricating oil's abilities of extreme pressure, anti-wear and reduce frictional resistance, and the key is the nanometer particles in the lubricating oil are dispersed equably.This paper gave a review on the development of lubricating oil and its additives. Furthmore, the theory and practical methods for dispersion of nanometer particles in liquid phase were introduced and discussed.To disperse nano Cu powder in lubricating oil , a series of polyglyceryl fatty acid ester(PGFE ) was synthesized. The lypohydrophilic characters of polyglyceryl fatty acid esters were adjusted by changing the contents of fatty acid and the degree of polymerization N in the dispersant molecules. The studies on sedimentation and rheology show that the Cu particle suspension added with a dispersant of polymerization N of 6 and the mass ratio of stearic acid of 65% in the dispersant molecule is the most stable. When the concentration of the dispersant is 1.5% of solvent weight, the effect on rheological property of the lubricating oil is slighting. To analyze the adsorption mechanism between nano copper surface and the polymer dispersant, TG and FT-IR spectra were measured. And the results indicated that the coordination of the functional groups of -COOR and-OH to the surface of Cu makes polymer adsorb to the surface of Cu, and affect performance of dispersant directly.Another kind of dispersant alkylbenzotriazole was synthesized from halohydrocarbon and benzotriazole to improve nano Cu powder dispersing in the lubricating oil . The dispersant was analyzed by IR and NMR. The experiements for sedimentation and rheology show that the suspension became more stable when the...