Electrosteric Control of the Aggregation and Yielding Behavior of Concentrated Portlandite Suspensions.

Portlandite (calcium hydroxide: CH: Ca(OH)) suspensions aggregate spontaneously and form percolated fractal aggregate networks when dispersed in water. Consequently, the viscosity and yield stress of portlandite suspensions diverge at low particle loadings, adversely affecting their processability. Even though polycarboxylate ether (PCE)-based comb polyelectrolytes are routinely used to alter the particle dispersion state, water demand, and rheology of similar suspensions (e.

Temperature-Induced Aggregation in Portlandite Suspensions.

Temperature is well known to affect the aggregation behavior of colloidal suspensions. This paper elucidates the temperature dependence of the rheology of portlandite (calcium hydroxide: Ca(OH)) suspensions that feature a high ionic strength and a pH close to the particle's isoelectric point. In contrast to the viscosity of the suspending medium (saturated solution of Ca(OH) in water), the viscosity of Ca(OH) suspensions is found to increase with elevating temperature.