Rižikovs, J., *, Zandersons, J., Paže, A., Tardenaka, A. and Spince, B. 2014. Isolation of Suberinic Acids from Extracted Outer Birch Bark Depending on the Application Purposes. Baltic Forestry 20(1): 98-105.

The research applies to the woodworking industry and the utilisation of bark for obtaining of saturated higher fatty acids, containing reactive hydroxyl and epoxy groups, which are promising raw materials for the synthesis of high added value derivatives for cosmetics, emulsion production, the polymer industry, etc. Therefore, the application of the results of our investigation has synergy with material science. The aim of the investigation was to increase the utilization efficiency of birch bark and to inform the specialists of the forestry and wood industry about the wide scope of high added value products, which could be produced from this valuable raw material. The fractionation of suberinic acids by sedimentation in certain ranges of the alkaline-alcohol solution pH 4.7-6.0 made it possible to obtain suberinic acids with the content of 9,10-epoxy-18-hydroxy octadecanoic acids up to 58% oven dry suberinic acids fraction.

The mixture of suberinic acids obtained by alkaline-water depolymerisation acts as an excellent binding agent to produce medium and high density formaldehyde free particle boards with low thickness swelling and high bending strength. The biobased rigid polyurethane foams obtained from suberinic acids polyols also demonstrate good mechanical properties.

Key words: Birch bark, depolymerisation, suberinic acids, particle boards, polyurethane foams.