Dimensional stability of wood modified by citric acid using different catalysts
Research subject and fields:
Small wooden samples of fir (Abies alba Mill.) and beech (Fagus sylvatica L.) were chemically modified by citric acid (CA) as non-formaldehyde cross-linking system reagent and cured by convection heating at three different temperature regimes. Two different CA solutions were used, one with NaH2PO2 and the other with NaH2PO4 as a catalyst. The dimensional stability of the modified wood was determined by the anti-swelling efficiency (ASE) using the water soak/oven dry method. Almost equally large improvement of dimensional stability of wood was attained using NaH2PO4 as when NaH2PO2 was applied as a catalyst.