Poly(vinyl pyrrolidone), a dispersant for non-aqueous processing of silicon carbide

In this paper, poly(vinyl pyrrolidone) (PVP) was selected as a dispersant for preparation of high concentrated silicon carbide (SiC) slurries in an ethanol (EtOH)/methyl ethylene ketone (MEK) solvent system. The interactions between (1) solvent and powders, (2) the solvent and dispersant, and (3) dispersant and powder were characterized in terms of adsorption and viscosity measurement. It was evidenced that the dispersion of SiC slurries was highly dependent on the solvent composition. Well-stabilized SiC slurries could be obtained using PVP as a dispersant in EtOH/MEK media with the content of EtOH in the 40-50 wt% range. The optimal dosage of PVP as a dispersant was at a PVP/SiC mass ratio of 17 mg/g. Results showed that PVP was an effective dispersant for SiC in EtOH/MEK media.