Due to its unique supramolecular structure, cellulose is widely used as a template agent, ensuring an easy structuring of anatase TiO2 particles with subsequent release after the organics burning. This work is devoted to the synthesis of microcrystalline cellulose-TiO2 (MCC-TiO2) composite photocatalyst by preserving the intermediate organic-inorganic structures. A series of the MCC-TiO2 materials were prepared via solvothermal sol-gel method in n-decane and caproic acid solvents and characterized by X-ray diffraction, transmission electron microscopy, IR spectroscopy, 1 Н NMR and TG/DSC methods. The photocatalytic activity of the prepared materials was evaluated by the decomposition of formic acid in aqueous solutions. The composites failed to be formed in n-decane, while in caproic acid, acting as solvent and reagent, anatase TiO2 nanoparticles were formed onto the crystalline domains of cellulose, tightly fixed due to covalent Ti-O-C bonds. The materials formed in caproic acid showed a higher photocatalytic activity, explained by a complementarity of the organic and inorganic components. The specific activity (normalized on TiO2 mass) of best synthetized composite materials was almost twice higher than that of Aeroxide P25 TiO 2 reference photocatalyst.

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Features and characteristics of wood as a natural smart material allow us to use it to create new smart biocomposite materials, intelligent systems and environments. The shape-memory effect of oak (Quercus robur L.) and birch (Betula pendula Roth) veneers was investigated. Thermomechanical spectrometry was used to study these two species, which makes it possible to establish the relationship between the deformation transformations and the nature of intermolecular interactions and the interchain organization of wood polymers. The quantitative and molecular relaxation characteristics of the topological structure were obtained for the characterization of the shape-memory effect for the permanent, temporary and after recovery shapes of birch and oak wood samples. The results showed a relationship between the quantities of shape-memory effect and changes in the molecular-topological structure. A reversible transformation of a topological structure was experimentally confirmed for birch and oak woods, with the formation of a temporary deformation and the recovery of the original permanent shapes.

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