Improved performance of thermally modified wood via impregnation with carnauba wax/organoclay emulsion

Thermally modified wood (TMW) presents several disadvantages, such as poor mechanical properties and vulnerability to ultraviolet exposure, which limit the application of TMW in the construction industry. To address the aforementioned shortcomings, carnauba wax emulsions containing efficiently dispersed organoclay (0, 0.5, and 1.0 wt%) were prepared as modifiers for the post-treatment of thermally modified loblolly pine (Pinus taeda). Morphological observation confirmed that the carnauba wax/organoclay complex coating was formed in the tracheid lumen, and organoclay layers successfully penetrated into the wood cell wall. The efficiency of the carnauba wax/organoclay emulsion in improving the quality of TMW was evaluated. The results showed that carnauba wax/organoclay emulsion positively affected TMW, reducing its water uptake, increasing its bending and compressive strengths, maintaining its constant color and gloss under weathering, and decreasing metal corrosiveness. In most cases, the higher the organoclay loading, the better the performance of TWM. Thus, TMW impregnated with carnauba wax/organoclay emulsion shows potential as a potential construction material for outdoor applications.