The study on the synthesis and action mechanism of starch succinate half ester as water-reducing agent with super retarding performance

In this paper, starch succinate half ester (SSHE) was synthesized by a simple method and used as water-reducing agent. The effects of both dosage of SSHE and storing time on the fluidity of cement paste and ζ-potential of cement particles were studied in comparison with that of carboxymethyl starch (CMS) whose dispersion ability mainly depends on steric hindrance effect. The results indicate that SSHE is a novel kind of water-reducing agent with super retarding performance. The main dispersion capacity of SSHE comes from steric hindrance repulsion rather than electrostatic repulsive force and the super retarding performance results from the introduction of reactive succinate half ester groups in acid form.