Dynamics of absorption and evaporation of organic solvents in electrically conductive wood

Wood, a hygroscopic material, is sometimes exposed to organic solvents for decoration or protection. Compared with measuring moisture contents, it is still challenging to estimate the degree of the absorption and evaporation of organic solvents in wood. In this work, we investigated the dynamics of absorption and evaporation of various organic solvents in the wood by monitoring a change in an electric current. To realize this, we fabricated an electrically conductive wood by coating the walnut timber with multi-walled carbon nanotubes (MWCNT). Then, organic solvents such as ethanol, n-hexane, acetone, toluene, benzene, and isopropyl alcohol were dropped in the MWCNT-treated wood under controlled voltage conditions. The current was changed differently during the absorption and evaporation of the solvents in the woods. As a result, we found that polar and nonpolar solvents exhibited different degrees of absorption and evaporation in walnut wood. Acetone and n-hexane are polar and nonpolar organic solvents absorbed and evaporated rapidly in the conductive wood among organic solvents. In addition, we found that the absorption and evaporation dynamics obeyed different mathematical models. Our work paves the way to study the absorption and evaporation of organic solvents in the frame of electrically conductive wood.