Effect of polyvinylpyrrolidone on rheology of aqueous SiC suspensions dispersed with poly(aspartic acid)

Poly(aspartic acid) (PASP) as environmental friendly and biodegradable polymer has been considered to replace polyacrylic acid (PAA) for years. In this work, effect of polyvinylpyrrolidone (PVP) on the rheological properties on aqueous SiC suspensions dispersed with PASP was investigated. PASP (0.3 wt%) and PVP (0.1 wt%) co-stabilized suspensions at different pH and solid loadings can achieve better dispersion at lower dosages of dispersants than those with only PASP (0.7 wt%). The complex of anionic PASP molecules and nonionic PVP molecules through intermolecular hydrogen bonding provided enhanced steric hindrance, and resulted in improved stability.

Graphical abstractPoly(aspartic acid) (PASP) can well disperse aqueous SiC suspensions. Small addition (0.1 wt%) of PVP had a significant influence on the rheological behavior of SiC suspensions dispersed with PASP. The association of PVP molecules with the PASP molecules provided enhanced steric hindrance for the SiC suspensions.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlight► PASP can replace PAA in dispersing aqueous SiC suspensions. ► Small addition of PVP improved the rheology of SiC suspensions with PASP distinctly. ► The mixture of PASP and PVP provided enhanced steric hindrance for the SiC suspensions.