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

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