We prepared surface coatings based on liquefied wood. Black poplar wood with diethylene glycol and glycerol as reagents and sulphuric acid (VI) as a catalyst were used for liquefaction. Three types of liquefied wood were prepared, to which melamine-urea-formaldehyde resins (Meldur H97, Meldur IV and Meldur MS4) were added. Various coating formulations were prepared. From these, one formulation for each type of liquefied wood was selected for further testing. The selected coatings were cured in a drying chamber at 135 °C for 1 hour. The hardness and flexibility of the coatings, the coating adhesion to the surface, the resistance of the coating to cold liquids and the resistance to dry and wet heat were determined. The results were compared with the properties of a commercial waterborne, two- component coating. We concluded that the hardness of the coating is decreasing slowly from the time of consolidation. The test results of the resistance of the coating to cold liquids showed that the new coatings have reduced resistance to water, coffee and alcohol, while their resistance to oil and acetone is comparable to the resistance of the commercial coating. Furthermore, the infrared (FT-IR) spectra analysis of liquid and cured films of the coatings was performed, which showed the occurrence of new absorption bands on the spectra.
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