Dimensional stability of wood modified by citric acid using different catalysts Stabilnost dimenzija drva modificiranoga limunskom kiselinom uz razli~ite katalizatore

ABSTRACT • Small wooden samples of fir (Abies alba Mill.) and beech (Fagus sylvatica L.) were chemically mo-dified by citric acid (CA) as non-formaldehyde cross-linking system reagent and cured by convection heating atthree different temperature regimes. Two different CA solutions were used, one with NaH 2 PO 2 and the other withNaH 2 PO 4 as a catalyst.The dimensional stability of the modified wood was determined by the anti-swelling efficiency (ASE) using the wa-ter soak/oven dry method. Almost equally large improvement of dimensional stability of wood was attained usingNaH 2 PO 4 as when NaH 2 PO 2 was applied as a catalyst. Keywords: dimensional stability of wood, beech wood, fir wood, chemical modification, citric acid, NaH 2 PO 2 ,NaH 2 PO 4 SA@ETAK • Mali drveni blokovi jelovine i bukovine kemijski su modificirani neformaldehidnim sustavom zaumre`avanje – limunskom kiselinom (CA), u trima razli~itim temperaturnim re`imima. Upotrijebljene su dvije oto-pine limunske kiseline. U jednoj je katalizator bio NaH