Effect of β‐cyclodextrin pendant on the dispersion robustness of polycarboxylate superplasticizer toward kaolin

Abstract

Two types of polycarboxylate superplasticizers (PCEs) with β‐cyclodextrin (β‐CD) as pendant groups were synthesized by different methods to employ monovinyl β‐CD monomer (MA‐β‐CD), and their dispersion robustness toward clay was evaluated by the dosage to achieve the specific spread value of the cement paste in the presence of 3 wt% kaolin. The interaction mechanism was investigated by X‐ray diffraction analysis and adsorption measurement, and it was proposed that the sorption of PCEs on the surfaces of kaolin particles was weakened by β‐CD pendants due to their pronounced steric hindrance effect. The results demonstrated that PCE with higher contents of β‐CD pendants, which was synthesized via partially replacing poly(ethylene oxide) monomer by MA‐β‐CD, was more tolerant toward kaolin. POLYM. COMPOS., 39:755–761, 2018. © 2016 Society of Plastics Engineers