Functional silicones used as a potential tool for the development of non-biocidal wood treatments
F Lhumeau, C Delaite, F Marchal, F Pochon, M Kutnik
The increase of wood resistance against biological agents for outdoor use is conventionally performed by deep impregnation with preservatives. However, some of the traditional wood preservatives, used for decades for wood protection and regarded as the most effective, are currently subjected to severe restrictions because of their toxicity. In fact, new preservation technologies are constantly entering the wood protection market. Silicones are commercially used as hydrophobic agents in several industrial applications. In this study, small Scots pine (Pinus sylvestris) specimens were impregnated with silicone-based solutions and emulsions in order to increase wood hydrophobicity. Silicones used were previously functionalized with specific functions able to graft to the hydroxyl groups responsible for the wood hygroscopic nature. The silicones grafting on wood limit water uptake and their potential release to the environment. The results of the relative water uptake showed that several formulations significantly reduce the water content of wood by either filling wooden cavities or impeding water absorption. Silicones faintly functionalized present the better water uptake diminution while silicones with high functionalization level cannot reduce water uptake due to their hydrophilic character produced by the specific functions.