Study the Effect of Some Surfactants on the Properties of Cement Pastes

Abstract

A comparative study is carried out between the effect of adding different percentages of each of the amphoteric surfactant coca amido propyl betaine (CAPB) , cationic surfactant alkyl dimethyl hydroxyl ethyl ammonium chloride ( HYPR), nonionic surfactant cocamide DEA(LM) and the anionic surfactant sodium dodecyl benzene sulphonate (SDBS) to some Portland cement pastes. The influence of the different surfactant concentrations and the mixing time on the air content of the pastes and accordingly on the bulk density, compressive strength and microstructure of the hardened cement specimens is discussed .The optimal levels of factors to achieve the desired goals are determined. The results showed the preference of using LM over SDBS when low dosage of entrained air up to 9% is required because LM enhances the compressive strength. Also, CAPB is preferred more than HYPR when more dosage of entrained air is required.