Preparation of Two-Component Polyurethane Coatings from Bleached Liquefied Wood
Arnaud Maxime Cheumani-Yona,
Franc Budija,
David Hrastnik,
Andreja Kutnar,
Matjaž Pavlič,
Pavel Pori,
Črtomir Tavzes,
Marko Petrič
Affiliations
Arnaud Maxime Cheumani-Yona
Institute of Wood Science and Technology and Sustainable Development, Celovška cesta 268, 1000 Ljubljana, Slovenia; Department of Wood Science and Technology, Biotechnical Faculty, University of Ljubljana, Jamnikarjeva 101, 1000 Ljubljana, Slovenia; Slovenia
Franc Budija
Institute of Wood Science and Technology and Sustainable Development, Celovška cesta 268, 1000 Ljubljana, Slovenia; Slovenia
David Hrastnik
Department of Wood Science and Technology, Biotechnical Faculty, University of Ljubljana, Jamnikarjeva 101, 1000 Ljubljana, Slovenia; Slovenia
Andreja Kutnar
Institute of Wood Science and Technology and Sustainable Development, Celovška cesta 268, 1000 Ljubljana, Slovenia Andrej Marušič Institute, University of Primorska, Muzejski trg 2, 6000 Koper, Slovenia; Slovenia
Matjaž Pavlič
University of Ljubljana, Biotechnical Faculty, Jamnikarjeva 101, 1000 Ljubljana, Slovenia; Slovenia
Liquefied wood-based polyurethane wood coatings of an aesthetically acceptable light colour were prepared and characterised. Liquefied black poplar wood was obtained by solvolysis in a polyethylene glycol/glycerol mixture, and it was bleached with hydrogen peroxide. The bleaching treatment converted liquefied wood from a dark brown to a yellowish product. Polyurethane films were prepared by the curing of liquefied wood with polymeric diphenylmethane diisocyanate or trimethylolpropane toluene diisocyanate prepolymer (TMP/TDI) isocyanate-type hardeners. It was found that the selected properties of the films prepared from the bleached liquefied wood were, in general, equivalent to those prepared from unbleached liquefied wood. The mechanical properties of the films obtained with the TMP/TDI curing agent were acceptable for wood coating applications. The initial poor resistance of the films to water and ethanol was substantially improved by the addition of n-octyltriethoxysilane to the liquefied wood prior to the preparation of the polyurethane coatings; the hardness of the films also increased.
