Using liquefied wood the production of polyurethane foam was optimised. Wood was liquefied on the basis of already known methods, then linear polyester was produced, and later used to make polyurethane foams. To produce liquefied wood poplar sawdust, dietilenglycol and sulphur(VI)acid were used. Anhydride of phtalic and adipic acid were used for etherification. Nine different foams were produced. It was found out that the density of all the foams was similar, and that all the foams absorbed water very well. The foams are suitable for use in florist shops.