Superplasticizers cause dispersion into smaller agglomerates of cement particles which predominate in the cement paste of the concrete mixture. Due to the dispersion effect, there is a fluidity increase in the cement mixture. In the past time the dispersion effect was ascribed only to the development of the same electrostatic (negative) charge on the cement particles (25). The attractive forces existing among cement panicles and causing agglomeration would be neutralized by the adsorption of anionic polymers negatively charged, such as SNF or SMF, for the presence of SO ‘ groups on the surface of cement particles. The dispersion of cement particles would be related with the elecmcal repulsion produced by the adsorption of negatively charged groups (Fig. 3) and determined through zeta potential measurements.
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