The Changes in the Acoustic Properties of Western Red Cedar due to Methanol Extraction

The changes in acoustic properties of the heartwood portion of Western red cedar (Thuja plicata) due to methanol extraction were investigated. Longitudinal strips were cut from heartwood and adjacent sapwood parts of 4 different Western red cedar trees, and the Young's modulus per specific gravity (E/γ) and values of loss tangent (tan δ) were measured by the free-free flexural vibration method before and after methanol extraction. Tha angular distribution of microfibrils in the cell walls of both heartwood and sapwood portions for each tree were measured using an X-ray diffractometer (...)