Effect of typical clay upon the dispersion performance of polycarboxylate superplasticizer

Abstract

The effect of three typical commercial clays (Na-MMT, Illite and Kaolin) upon the dispersion of polycarboxylate (PCE) was investigated by mini slump test and viscosity analysis. PCE adsorption on clays or cement was determined by method of total organic carbon. Mini slump test results showed adding more than 2% Na-MMT or adding 4% kaolin will significantly affect the fluidity of cement pastes, but Illite affect the fluidity of cement pastes slightly. The viscosity test shown in order to achieve the same plastic viscosity(0.15% PCE dosage), PCE is employed at a dosage of 0.45%, 0.24% and 0.2% bwoc respectively as the case of adding 2% Na-MMT, kaolin and Illite. The total organic carbon shown that the order of PCE sorbed amounts is Na-MMT, Kaolin, cement and Illite.