Due to increasing concerns for the environment, the industry and research institutions are looking for new ways to protect wood. One of the most promising methods of improving the properties of wood is chemical modification using silanes. For the purposes of this diploma thesis, hydrophobing of spruce wood was carried out by applying a 1 % hexane solution of a silane from the series of alkyl-trichlorosilanes. The silane solution was applied to the wood either by brushing or immersing it in the solution for various times. The chemical modification of spruce wood with the silane increased the water contact angles on samples by up to 140°. At the same time, the capillary-driven uptake of liquid water into the samples was reduced. We also determined that impregnation with silane has almost no effect on the wood%s equilibrium moisture content (EMC). The difference between the EMC of silane-impregnated wood and untreated wood had a value of only 0.9 %. The anti-swelling efficiency (ASE) was determined in two different ways. The first approach involved immersing samples in water under normal atmospheric pressure and the second involved impregnating the samples with water by applying a combination of exposure to a vacuum and increased pressure. In both cases, similar results were obtained. ASE was higher the longer the silane treatment time lasted. ASE values of up to 17.5 % were achieved.
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