Fluidity and Mechanical Properties of Cement Mortars Containing Poly (ethylene-co-vinyl acetate) Emulsions

Abstract

Polymer cement mortar composed of poly (ethylene-co-vinyl acetate) (EVA) emulsion containing various kinds of stabilizer was investigated. Emulsion containing anionic emulsifier showed poor miscibility with cement. Addition of nonionic emulsifier to the emulsion improved the miscibility. Emulsion containing poly (vinyl alcohol) s (PVAs) as protective colloids and emulsion containing both hydroxyethylcellulose and nonionic emulsifier revealed good miscibilities. Apparent viscosity for polymer cement mortar composed of both kinds of emulsion or poly (styrene-co-butadiene) latex as a reference were measured at various shear rates. The polymer cement mortar composed of the emulsion containing PVA showed lower viscosities at low shear rates and higher viscosities at high shear rates compared with the other polymer cement mortars as well as a plain mortar. Casson plots of the data obtained above gave almost straight lines. Compressive, flexural and adhesive strength of the polymer cement mortars were measured. Unit weights of the wet mortars affeted the strengths to a great extent. Neither the kind of stabilizer nor the type of the polymer used showed difference in the strengths of the mortars.