Interaction of silylated superplasticizers with cementitious materials

Incorporation of silane groups into polycarboxylate superplasticizer (PCE) opens a new technical approach to improve properties of PCE, such as to enhance the adsorption of PCE on cement and hence the dispersing performance, to minimize the retardation effect, and potentially to increase mechanical strength of cement mortars. Silylated PCEs were synthesized using silane monomer via radical copolymerization. Dispersing effect, adsorption behaviors, and influences on mortar strength of these polymers were systematically investigated. Results show that increasing the incorporation of sliane groups in PCE promotes the adsorption of polymer on cement surface and hence leads to good fluidity retention capability. Furthermore, sulfate resistance ability of silylated PCE is superior due to stronger chemical adsorption of polymer on cement surface. The retardation effect of PCE is minimized by the introduction of silane groups. The addition of silylated PCE significantly increases 3days compressive strength without notably affecting the long-term strength. (c) 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 44161.