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For practical applications of poled electrooptic polymers, highly efficient and thermally stable nonlinear optical (NLO) chromophores are required. We describe here a concise synthesis and characterization of a series of donor−acceptor chromophores incorporating a bithiophene moiety in the conjugated bridge. They display a suitable thermal stability and significantly enhanced molecular nonlinearity as compared to their monothiophene analogues and are among the most efficient yet stable NLO chromophores prepared so far.

Natural polymers, such as alginate and gelatin, can be used to produce scaffolds for tissue engineering applications; but, their mechanical and biochemical performance should be improved. A possible solution to obtain this result, is the generation of multi-component scaffolds, by blending two or more polymers. One way to realize it, is the formation of an interpenetrating polymer network (IPN). In this work, the interpenetration of alginate and gelatin hydrogels has been successfully obtained and preserved by supercritical CO 2 (SC-CO 2 ) drying performed at 200 bar and 35˝C, using different blend compositions: from alginate/gelatin = 20:80 v/v to alginate/gelatin = 80:20 v/v. The process allowed modulation of morphology and mechanical properties of these blends. The overall result was made possible by the supercritical drying process that, working at zero surface tension, allows preserving the hydrogels nanostructure in the corresponding aerogels.

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The synthesis of 4'-hydroxyphenyl(4-hydroxy-3-allyl)azobenzene is reported. The molecule is mesogenic and it can be used for preparing nematic main-chain segmented polymers. The nematic phase is the result of the effect of the side allyl group which, while it destabilizes the crystalline phase, does not affect the occurring of the nematic order. In the crystalline state, a large hexagonal unit cell containing five to six chains is observed for polymers with longer flexible spacer in the chain. Chloroform solutions and thin films of polymers absorb in the UV-visible range, at approximately 332 and 439 nm, corresponding to the p - p* and n - p* electronic transitions of azoaromatic chromophores, respectively. Under appropriate UV irradiation we have obtained the photoisomerizations trans-cis and cis-trans, which are fully reversible in the case of solutions. In the solid state a photostationary state is reached

A series of zinc complexes with tridentate pyridinoylhydrazone ligands bearing two different end groups and coordinated pyridine molecules were synthesized and characterized. Crystal structures with mono‐, di‐, and polymeric arrangements were obtained, depending on the position of the pyridinoyl nitrogen atom. Direct involvement of the pyridinoyl moiety in the coordination to the metal was observed when the nitrogen was in the ortho or meta position. The meta derivatives led to 1D polymers with the same coordination environment, regardless of the bulkiness of the end group. In this case, unprecedented solid‐state photoluminescence quantum yields were recorded. In the ortho ligands, the further bidentate N,N site involving the pyridinoyl nitrogen atom was able to coordinate a further zinc acetate unit. Molecular and periodic calculations were performed within density functional theory (DFT) to rationalize the photophysical behavior. Excellent agreement between the theoretical and experimental absorptions was observed. The HOMOs and LUMOs of the complexes were investigated both in the solid state and in solution.