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Liquefied wood is a potential alternative to the synthetic adhesives which are used for the bonding of wood. Despite the ability of liquefied wood to self-crosslink, bonds formed during the bonding of wood with liquefied wood do not achieve sufficient shear strength and have poor resistance to water. For this reason the process of the curing of liquefied wood, the influence of various parameters on the shear strength of bonds, and the structure of bonds formed during the bonding were analyzed. It was found that the chemical curing of liquefied wood started after water and solvent had been removed from it. When bonding wood, the curing liquefied wood takes place faster because, in addition to evaporation, the transition of both vaporous components from the liquefied wood to the lamellas also occurs. During the bonding of 5 mm thick beech lamellas with liquefied wood having a negative pH, at optimal bonding conditions (180 °C, 12 min), a specific type of bond was formed. It consisted of a central part of carbonized wood cells of the bonded lamellas and the cured liquefied wood, and a narrow layer of partly delignified wood cells at the border between the central part and bonded lamella.

Due to the increasing global production of wood based panels (particleboards, fiberboards, and plywood) problems with raw material and difficult treatment of recovered wood based panels after life cycle occur. Inorganic pollutants represent the main problem of raw material while treatment of recovered wood-based composites is aggravated due to the presence of synthetic adhesives. Latter and the release of methane during anaerobic decomposition are reasons for using alternative methods instead of sending these composites to landfills. The most promising methods of recovered wood-based panels treatment are: hydrothermal recycling, re-manufacturing of panels, combustion and pyrolysis, composting, re-use and some other less used methods for processing of new recycled products.

Wood liquefaction is the process of wood solvolysis in which basic wood components are degraded to monomers and oligomers in the presence of a suitable solvent and catalyst. These later on react with each other or with the solvent, and insoluble product is produced. The paper describes the mechanisms and kinetics of wood liquefaction and liquefaction of its basic components (cellulose and lignin).

Liquefied wood is a potential alternative to the synthetic adhesives which are used for the bonding of wood. Despite the ability of liquefied wood to self-crosslink, bonds formed during the bonding of wood with liquefied wood do not achieve sufficient shear strength and have poor resistance to water. For this reason the process of the curing of liquefied wood, the influence of various parameters on the shear strength of bonds, and the structure of bonds formed during the bonding were analyzed. It was found that the chemical curing of liquefied wood started after water and solvent had been removed from it. When bonding wood, the curing of liquefied wood takes place faster because, in addition to evaporation, the transition of both vaporous components from the liquefied wood to the lamellas also occurs. During the bonding of 5 mm thick beech lamellas with liquefied wood having a negative pH, at optimal bonding conditions (180 °C, 12 min), a specific type of bond was formed. It consisted of a central part of carbonized wood cells of the bonded lamellas and the cured liquefied wood, and a narrow layer of partly delignified wood cells at the border between the central part and bonded lamella.