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Relationships between microstructure and mechanical properties in SPS‐Zn/PEG blends are investigated. Ion/dipole interactions induce the miscibility of both blend components for PEG content up to 10 wt.‐% as evidenced by DSC and TEM observations. Elemental mapping by EFTEM was used to investigate the ionic cluster microstructure and the phase structure in the blends. PEG chains do not hinder the formation of ionic multiplets but modify the microstructure of the clusters. Moreover, a PEG‐rich layer is observed in the vicinity of the aggregates surface. As a consequence, no cluster glass transition is observed in DMA experiments for these blend systems and besides, the absence of ionic plateau is assigned to the decrease in the ionic clusters' stability.magnified image

Addition of commercially available 2‐isocyanatoethyl methacrylate to a water solution of potassium bisulfite unexpectedly yields an anionically charged hydrogel. Structural analysis shows the presence of sulfonato‐blocked isocyanates (with no detectable residual isocyanates), a full polymerization of the vinyl groups, and the appearance of urea functional groups. A mechanism is proposed to explain the gel formation, based on a combination of bisulfite‐initiated free‐radical polymerization, crosslinking by urea bridge formation, and addition of bisulfite ions to isocyanate groups. Some basic physical properties (TGA, swelling) of the gel are presented.magnified image