Liquefaction of wood, synthesis and characterization of liquefied wood polyester derivatives



Liquefaction of Central-European softwoods meal was performed using a mixture of diethylene glycol and glycerol and a minor addition of p-toluenesulfonic acid as a catalyst. The liquefied wood was used as a replacement of a certain amount of the polyhydroxy alcohol in the polyester synthesis, enabled by the large number of hydroxyl groups that were available in the liquefied wood. Three different polyesters were synthesized by using adipic acid and phthalic acid anhydride as reagents. The products were characterized using FTIR, GPC/SEC, and viscosity measurements. The polyesters have hydroxyl values that were reduced due to esterification, from 1043 mg KOH/g of the liquefied wood to 400–800 mg KOH/g. Polyhydroxyl alcohols (22–23%) in the polyester formulations were replaced by wood derivatives. Such saturated polyesters are suitable for further use in polyurethane foam production. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010