화학공학소재연구정보센터
Journal of the American Ceramic Society, Vol.88, No.4, 833-838, 2005
Influence of sucrose addition on rheology of alumina slurries dispersed with a polyacrylate dispersant
The effect of sucrose addition on rheology of alumina slurries, dispersed with a polyacrylate dispersant (Darvan 821 A), was studied for different alumina loading. Smaller amount of sucrose addition (10 wt%) had a more significant influence on rheological behavior of the slurries than the incremental addition to 30 wt% sucrose. Addition of sucrose resulted in a decrease in the apparent yield stress, viscosity, thixotropy, and increase in non-Newtonian index as compared with the slurries containing just the polyacrylate, indicating weakening of the inter-particle network. Weakening of the inter-particle network arose from the enhanced steric hindrance because of the presence of sucrose molecules in association with the polyacrylate molecules adsorbed on alumina particle surfaces. This association is because of intermolecular hydrogen bond formation between free hydroxyl (-OH) groups of sucrose and carboxylate ions of polyacrylate molecules. Use of sucrose resulted in cast green bodies with higher strength.