The influence of cement composition on superplasticizers’ efficiency
نویسندگان
چکیده
Fundamental interactions between polymeric superplasticizers and cement are studied. Cements with different alite-, belite-, C3Aand C4AF-contents are used. The use of commercially available superplasticizers like melamine formaldehyde sulfite(MFS) and β-naphthalene sulfonic acid formaldehyde-(NSF) resins is investigated. These superplasticizers (industrial products) are characterized by means of their molecular weights and polymeric radii, as well as by estimating the anionic charge density in water and in the cement filtrate of four CEM I cements. Application data of the eight cement-superplasticizer-combinations (heat flow calorimetry and mini-slump tests) are obtained and the surface chemistry of the superplasticizers with cement (zeta potentials and superplasticizer adsorption on cement) is studied.
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