Study on Dispersion Properties of an Amphoteric Polycarboxylate Superplasticizer on Cement Pastes

摘要

A novel amphoteric polycarboxylate superplasticizer (APCs) was prepared by solution copolymerization from acrylic acid (AA), allyl polyethylene glycol (APEG), diallyldimethyl ammonium chloride (DMDAAC). Effects of DMDAAC dosage and monomers ratio on performance of APCs were investigated by tested of zeta potential of cement particles and adsorption on cement. Results indicated that introducing of cationic monomer can increase the saturation adsorption amount and dispersibility of APCS. When the molar ratio of AA and APEG and DMDAAC is 5:1:0.5, the dispersibility of APcs has the best adsorptivity and disersibility. The synergistic effects of Zeta potential and steric repulsion of the cement particles surface is the main mechanism for dispersion.