A simple method for determination of kinetics of radial, tangential and surface swelling of wood

The aim of this paper is to introduce an objective method for monitoring the swelling rates and the final values of swelling of hard and soft woods in the polar media. As can be concluded from the presented kinetic plots of sound and biodegraded beech wood and of mature and juvenile spruce wood, the method provides a possibility of recording the dimensional alterations of wood specimens from the first instant of their contact with polar media. The method provides the possibility of monitoring the swelling kinetics of wood within temperatures ranging between 20 and 60 oC. The data obtained by the presented method may be used for the assessment of wood behaviour in the environment with changing humidity and temperature, or in a direct contact with polar media

Selected properties of beech wood degraded by brown-rot fungus Coniophora puteana

U radu se objašnjavaju određene promjene fizikalnih i mehaničkih svojstava netenzijske, zdrave bukovine nastale kratkotrajnim i srednjetrajnim djelovanjem gljive Coniophora puteana, uzročnice smeđe truleži. Gljiva je tijekom svog razvoja i napredovanja prouzročila postupni gubitak mase i znatno smanjila gustoću bukovine. Biorazgradnjom se izrazito povećao sadržaj polarnih ekstraktiva, nestalo je celuloze i relativno se povećao sadržaj lignina u drvu. Navedene promjene bukovine očitovale su se izrazito povećanom interakcijom vode i drva, odnosno utjecale su na njegovu peremeabilnost i veličinu površinskog bubrenja. Boja drva postala je sme|a, a sjaj je nakon 60 dana izlaganja gljivi smanjen. VIS i FTIR spektralne kemijske analize potvrdile su znatne kemijske promjene bukovine.This paper reveals the alteration of selected physical and chemical properties of non-tension beech wood exposed to short- and medium-term degradation by the brown-rot fungus Coniophora puteana. The fungus caused a gradual mass loss and a significant decrease in wood density by the decay progression. Biodegradation increased the contents of polar extractives in wood markedly, it caused a substantial removal of cellulose and it relatively increased the contents of lignin in wood. The above mentioned alterations of beech wood were reflected in an expressively increased rate of wood/water interactions, influenced its permeability and the rate of surface swelling. Wood colour turned to brown, and its lightness was reduced after 60-day degradation. The chemical analyses, VIS and FTIR spectra confirmed significant chemical changes of beech wood

A simple method for determination of kinetics of radial, tangential and surface swelling of wood

The aim of this paper is to introduce an objective method for monitoring the swelling rates and the final values of swelling of hard and soft woods in the polar media. As can be concluded from the presented kinetic plots of sound and biodegraded beech wood and of mature and juvenile spruce wood, the method provides a possibility of recording the dimensional alterations of wood specimens from the first instant of their contact with polar media. The method provides the possibility of monitoring the swelling kinetics of wood within temperatures ranging between 20 and 60 oC. The data obtained by the presented method may be used for the assessment of wood behaviour in the environment with changing humidity and temperature, or in a direct contact with polar media