In the last few years, there is a noticeable increase in research of liquefied wood, used for fuel or as a raw material for polyurethane foam production. The possibilities of further usage of liquefied wood, as an adhesive for particleboards, were examined. In the laboratory conditions 3-layer particleboards with various portions of liquefied wood (10 %, 20 %, 30%, 40 %, 50 % and 75 %) were prepared. The wood was liquefied according the polyhydric method. We studied internal bond, surface soundness, thickness swelling and emission of free formaldehyde, determined by perforator procedure. It was found out that the internal bonds and surface soundness improved by addition of 10 % or 20 % liquefied wood. Concerning the thickness swelling, liquefied wood does not reduce the absorption of water, on the contrary, it does increase it. Emission of free formaldehyde highly reduces: the lowest level is gained by adding 20 % of liquefied wood.
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