Synthesis and Performance of Polyglyceryl Fatty Acid Ester Dispersants for Copper Powders in Lubricant

To disperse nano Cu powders in non-aqueous media,a series of polyglyceryl fatty acid ester(PGFE) were 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 sedimentation and rheology studies show that the most stable suspension is observed when the dispersant polymerization degree (n) is 6 and the mass ratio of stearic acid is 65%.When the concentration of the dispersant is 1.5% of solvent weight,there is a tiny effect on rheological property of non-aqueous media.To analyze the adsorption mechanism between nano copper surface and polymer,TG and FT-IR spectra are measured.And the coordination of the functional groups of -COOR and -OH to the surface of Cu made polymer adsorb to the surface of Cu,and affect performance of dispersant directly.