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A novel monovinyl β-cyclodextrin monomer (MA-β-CD; MA = methacrylate) was employed to synthesize polycarboxylate superplasticizers modified with β-CD as pendant groups, and their dispersing performance was tested in the absence and presence of montmorillonite. Adsorption measurement and X-ray diffraciton analysis indicated that their interactions with Ca-montmorillonite originated from electrostatic attractions between carboxylate groups and the positive charge of Camontmorillonite particle. Compared with conventional polycarboxylate superplasticizers (PCEs) only with poly(ethylene oxide) (PEO) chains, polycarboxylate superplasticizers with β-CD as pendants displayed enhanced robustness toward clay. This was attributed to the steric hindrance instigated from β-CD groups with the structure of a hollow truncated cone by hindering the sorption of polycarboxylate polymers on the surfaces of Ca-montmorillonite.

Phosphorescent conjugated polymers consisting of alternating p-phenylene-ethynylene and 'para-' or 'meta-type' Pt(II)-salphen luminophore units have been synthesized. Side-arms bearing different substituents (n-alkoxy and acetylated-sugar) have afforded contrasting emission properties that are attributed to the polymer conformation, extent of π-stacking interactions and differences in chemical structure. Intriguing selectivity in luminescent sensing of metal ions has been observed.

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Two types of polycarboxylate superplasticizers (PCEs) with b-cyclodextrin (b-CD) as pendant groups were synthesized by different methods to employ monovinyl b-CD monomer (MA-b-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 b-CD pendants due to their pronounced steric hindrance effect. The results demonstrated that PCE with higher contents of b-CD pendants, which was synthesized via partially replacing poly(ethylene oxide) monomer by MA-b-CD, was more tolerant toward kaolin. POLYM. COMPOS.,

The synthesis of soluble, conjugated poly­(Zn-salphen)-alt-(p-phenyleneethynylene)­s with a coilable structure and bearing acetylated sugar substituents is described, and their photophysical properties and conformational behavior have been investigated. Their CD spectra confirm that these systems are chiral, and signify ordered (helical) coiling of the polymer backbone arising from chirality transfer from the β-d-glucopyranosyl groups. The consequences of varying side-chain substituents as well as the extent of inter- and intrachain [π-stacking and Zn···O­(salphen)] interactions have been studied, and comparisons with the corresponding linear-rod and Pt-based congeners have been made. Analysis of the effects of different solvents on these systems by UV–vis absorption, emission, and CD spectroscopy indicates that low-polarity solvents give a tighter, more compressed helical structure with increased CD intensities, while coordinating solvents can perturb the folded conformation to afford a more extended coiled structure with decreased Cotton effects. These observations, together with variable-temperature CD experiments, point to the flexibility and dynamic nature of the helical conformation.

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