The compatibility of polycarboxylate-type superplasticizers with cement

Abstract

Four polycarboxylate-type (PC) superplasticizers of different functional groups were used; their dispersing and retaining behaviors were analyzed through ZETA potential measurement, mini-slump test of cement paste and performance test of concrete. The experimental results show that the dispersing and flow-retaining ability of PC was determined by two factors of anionic groups and nonionic groups: the density of anionic groups −COO⁻ or−SO₃ ⁼ acted on the electronic repulsive force, and the length and proportion of nonionic graft groups of PEO in PC chemical structure affected the steric effect. The compatibility between PC superplasticizers and cement mainly dependent on the type of PEO groups; furthermore, adding mineral powders is good to the compatibility for high performance concretes (HPCs).

Keywords

PC superplasticizers / cement / compatibility

References

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