Production of Spherical Electrolytic Copper Powder from the Solution Containing Polyethyleneimine

It was investigated whether the spherical electrolytic copper powder could be electrolyzed by adding polyethyleneimine (PEI) in the electrolytic solution. In order to identify the optimum electrolysis conditions for the electrodeposition of spherical copper powder, we investigated the effect of molecular weight of PEI, the amount of PEI added, the current density, and the cathode material on the morphology of electrolytic copper powder. The electrodeposited copper powder was analyzed with a scanning electron microscope, a laser diffraction scattering particle size distribution measuring device, and an X-ray diffractometer. It was found that the spherical copper powder can be obtained by electrolysis at 3000 A·m−2 scraping copper powder every 10 to 60 s in solution containing 0.126 mol·dm−3 Cu2+, 0.5 mol·dm−3 free H2SO4 and 1.0 g·dm−3 PEI with average molecular weight 10000.