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Herein, we synthesized a series of siloxane-based poly(ionic liquid)s (PILs) with imidazolium-type species in the main chain via the multicomponent Debus–Radziszewski reaction. We employed oligodimethylsiloxane diamine precursors to integrate flexible spacers in the polymer backbone and ultimately succeeded in obtaining main-chain PILs with low glass transition temperatures (Tgs) in the range of −40 to −18 °C. Such PILs were combined with conventional hydrophobic vinylimidazolium-based PILs for the fabrication of porous membranes via interpolyelectrolyte complexation with poly(acrylic acid), which leads to enhanced mechanical performance in the tensile testing measurements. This study will enrich the structure library of main-chain PILs and open up more opportunities for potential industrial applications of porous imidazolium-based membranes. published

Herewith, we report a straightforward, experimentally simple, and environmentally benign synthetic strategy toward cyclocondensation polymers. Using a fully aromatic polyimide as model system, we d...

Shape-anisotropic particles are of broad interest, e.g., for colloidal crystals or applications at interfaces such as particle-stabilized emulsions. Despite the wealth of accessible shapes of inorganic particles, anisotropic homopolymer particles are to date mostly limited to objects derived from spheres (e.g., ellipsoidal or disk-shaped particles). Here, we report the synthesis of shape-anisotropic, angular polyimide particles by thermal solid-state polycondensation (SSP) of monomer salts. We prepare monomer salt single crystals of relatively narrow size and shape distribution by growth inside hydrogels, and solve their crystal structure. Polyimide particles are obtained by simple heating and retain the shape of the initial salt crystals. Using high-temperature X-ray diffraction, thermal analyses and microscopy techniques, we investigate the mechanism of the transformation. The obtained polyimide particles are temperature-stable up to 640 °C and virtually insoluble in any solvent. This work sheds more li...

Vitrimers, strong organic glass formers, are covalent networks that are able to change their topology through thermoactivated bond exchange reactions. At high temperatures, vitrimers can flow and behave like viscoelastic liquids. At low temperatures, exchange reactions are very long and vitrimers behave like classical thermosets. The transition from the liquid to the solid is reversible and is, in fact, a glass transition. By changing the content and nature of the catalyst, we can tune the transesterification reaction rate and show that the vitrimer glass transition temperature and the broadness of the transition can be controlled at will in epoxy-based vitrimers. This opens new possibilities in practical applications of thermosets such as healing or convenient processability in a wide temperature range.