| Sumari: | This work was aimed al assessing the decay resistance of acetylated Scots pine (Pinus sylvestris) sapwood against white (Corio/us versico/or) and brown (Coniophora puteana) rol fungí and the effect of pyridine as catalyst. Samples were decayed over pure cultures on 4% malt agar for twelve weeks, following the general procedures of the European Standard EN113. Additionally, the dimensional stabilityof wood given by acetylation was compared in the catalysed and uncatalysed chemical modification systems. The chemical modification provided resistance to the biodegradation ofthe wood against brown and white rol fungí. A greater leve! of acetylation was required to inhibit the brown rol, in comparison with the required leve! to preven! the white rol. The decay patterns and the weight loss recorded indicated that, pyridine as a catalyst did not influence the decay resistance of acetylated wood, when results werecompared within the same fungus species. The dimensional stability provided by acetilización, and measured by the antiswelling efficiency (ASE}, was satisfactory in both reaction systems, although the uncatalysed system was significantly more efficient. lt was concluded that the weight percentage gain due to chemical modification is a good indicator of the degree of permanent partía! swelling of the wood blocks, as well as of the dimensional stability and the resistance to decay of the acetylated wood.
|
|---|
