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Depolymerized polyethylene terephthalate and liquefied wood polyesters can be used as a polyol for the production of polyurethane/polyisocyanurate foams. In this research, liquefied wood was synthesized by using a combination of diethylene glycol and glycerol and due to the possibility of using glycerol that is a by‐product in biodiesel production, our goal was to use as much glycerol in the liquefaction reagent as possible. We determined the properties of the polyols, properties of produced foams, and explained their correlation. Greater amount of glycerol in the liquefaction reagent resulted in higher OH number, molecular weight, functionality, and viscosity of the polyol, as well as in longer cream time and tack free time in foam preparation. Glass transition temperature, density, and water absorption of the foam increased with increasing amount of glycerol in liquefied wood. Compressive stress increased up to 30% of the glycerol in the reagent and then reduced, while thermal conductivity was not affected. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41522.

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The main purpose of the current research was to determine the chemical structure of typical lignocellulosic residues generated in wood processing industries, fruit and vine growing activities, and the maintenance of green areas. Four characteristic groups of samples, e.g. wood sawdust, bark, tree prunings and the lignified residues of fruits were analysed for the content of ash, lipophilic and hydrophilic extractives, cellulose, hemicellulose and lignin. Gravimetric methods were used for the analyses, and the purity of individual isolated fractions was monitored by FTIR spectroscopy. The highest quantity of ash and low molecular weight extractive compounds was determined in bark and tree prunings, while concentrations of cellulose and total carbohydrates were highest in sawdust samples. Lignified fruit residues and bark proved to be rich sources of lignin. Because of their diverse chemical composition, all of the examined materials are potential feedstocks for the production of platform chemicals and other specific products within biorefinery processes.