Creating water-repellent effects on wood by treatment with silanes

摘要: Three types of silanes were tested for their ability to impart hydrophobicity solid wood samples: a tetraalkoxy silane bearing four hydrolysable alkoxy groups; two alkyl-trialkoxy silanes; and multifunctional oligomeric systems. The first applied as monomeric solutions pre-condensed sols. water uptake treated was considerably reduced, especially after treatment with waterborne systems, while gaseous not changed. Initial repellence most pronounced when fluoro-alkyl functional system used; however, longer submersion time (24 h), the reduction in strongly diminished. Wetting-drying cycles led samples sols alkoxysilanes, aqueous revealed enhanced water-repellent effects these tests. This explained by continued condensation unreacted silanol groups during wetting-drying cycles. X-Ray mapping silicon (SEM-EDX) showed that due HS 2909 is caused plugging main penetration pathways such pits, ray cells tracheids.