In the thesis paper the possibility of using liquefied wood as a material for manufacturing adhesives was researched. Poplar wood was liquefied; the process based on already investigated liquefaction processes using glycerol as the reagent for the liquefaction and the sulfuric acid (VI) as a catalyst. The first part of the study included the optimization of the liquefaction, and the second part monitoring the hardening of liquid timber in combination with the adhesive additives. The hardening of adhesive mixtures was monitored by determining the rheological properties of the rheometer and by measuring the dielectric properties of the adhesive during curing in a press. The selected mixtures of liquefied wood (LW) and phenol-formaldehyde (PF) glue were used to glue test pieces at different times of compression followed by testing the shear strength and the assessment of the proportion of wood fracture. The results showed that for gluing wood PF glue with the addition of a small proportion of LW can be used and thus improve the shear strength of the adhesive joints as well as the resistance to moisture or water. If for gluing a higher proportion of LW as PF is used, the bonded blocks can be used only in dry conditions.
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