STUDY OF THE WOOD MODIFICATION PROCESS WITH POLYCARBOXYLIC ACIDS AND MICROWAVE TRATMENT

摘要

Wood specimens of fir (Abies alba Mill) and beech (Fagus sylvatica L.) are chemically modified by polycarboxylic adds (PCA) and analysed by Fourier transform infrared (FT-IR) spectroscopy that is used to evaluate the differences between, convection and microwave curing. A new non-formaldehyde crosslinking system is composed of two most prominent PCAs, e.g. 1,2,3,4-butanetetracarboxylic acid (BTCA) and citric acid (CA). These reagents require a phosphono-based catalyst, thus a sodium hypophosphite (SHP) catalyst is used in the study. The effects of the PCAs treatment are compared with the previously introduced 1,3-dimethylol 4,5-dihydroxy-ethylene urea (DMDHEU) treatment. Further intensification of the processes of wood modification and an increase in the quality of wood-based materials is achieved by microwave treatment. Dimensional stability of the modified wood is determined by anti-swelling efficiency (ASE), using the water soak/oven dry method. The results revealed the improvement of ASE of thewood modified by PCAs, as compared by the DMDHEU treatment.