Selection of dispersant and dispersion mechanism of PVP on copper powders.

The stability and dispersion of Copper (Cu) powders in an aqueous medium impacts their performances. Thus the Cu powder suspensions were prepared by adding different stabilizers—sodium dodecyl sulfate (SDS), sodium dodecylbenzene sulfonate (SDBS), polyvinyl pyrrolidone (PVP), and hexadecyl trimethyl ammonium bromide (CTAB); the best surfactant was selected and its stability and dispersion were studied. The study systematically examined the effect of the stability of suspensions via sedimentation analysis, including solid–liquid ratio, the concentration of stabilizer, and dispersion time. The particle size, the stability of suspensions, phase composition, and microstructure of Cu powders were characterized by laser particle size analyzer, zeta potential, X-ray diffraction (XRD), transmission electron microscope (TEM), and scanning electron microscope (SEM). The results indicate that the stability of the suspension is improved with the addition of PVP due to the steric hindrance of PVP, and the growth and agglomeration of particles are retarded by the formation of a thick hydration layer with the optimizing concentrations, dispersion time, and solid–liquid ratio 10 g/L, 30 min, and 1:25, respectively. [ABSTRACT FROM AUTHOR]