Variation of the viscoelastic properties of wood as a surface finishes substrate

Abstract

The variation of the viscoelastic properties of wood during exposure to sunlight-type radiation of thin specimens of Abies grandis as a model of the thin surface film of solid timber was followed by thermomechanical analysis (TMA) tests in compression and in tension. For all the types of tests carried out, the TMA traces obtained present only a single inflexion point, which has been assigned to lignin softening. Sunlight radiation was found to have a degrading effect on lignin while the cellulose to hemicelluloses interactions do not appear to be worsened during exposure to the same. The softening temperature variation as a function of sunlight radiation exposure appears to be a parameter which can be used both to observe wood degradation as well as to control the effectiveness and durability of wood stabilization treatments.