Chemical kinetics analysis on stress relaxation of chemically treated wood

摘要

In order to clarify rheological properties of wood primary constituents, stress relaxation of untreated, delignified and hemicelluose-removed woods was determined under different moisture content conditions. The experimental data were analyzed using a chemical kinetics approach that is based on a molecular level. The results indicated that both activation volume and activation energy for untreated wood decreased with increasing moisture content. But for delignified wood and hemicellulose-removed wood, they had a great change. Some suggestive explanations were given for the variations in activation energy and activation volume of chemically treated woods. The resultant finding was that the lower the activation energy, the smaller the interaction between wood primary components. The average relaxation rates obtained through the same experimental data changed in contrary direction comparing to activation energy. This proved the validity of the chemical kinetics approach in describing stress relaxation behavior of chemically treated woods under various moisture content conditions.