The thermal modification of wood is a modern procedure which improves the dimensional stability of wood and its resistance. In such a way protected wooden- window is better in quality and more competitive in market. In the thesis the influence of the thermal modification on the quality of bonding window profile from spruce wood was investigated. Spruce wood and three different types of adhesives were used (PVAc, PU, EPI) to bond thermal modified and non-modified wood (technical dry).The shear strength adhesive bond and percentage of wood failure were determined according to the EN 392. To find out the influence of water on adhesive bonds, part of specimens were soaked in water for 24 h at room temperature. It was found out, that after thermal modification the properties of spruce wood was changed, which has direct or indirect influence on adhesive curing and quality of adhesive bonds. The test results of the shear strength showed that the thermally modified wood can be bonded with (PU and EPI) adhesives. To assure the quality of adhesive bonds in thermally modified wood, the method of bonding needs to be adapted. The both types of adhesives cure chemically and for the reaction they need higher moistur content as the modified wood has. Therefore, the surfaces of wood have to be additionally wetted during the bonding, and the time of pressing has to be increased. The quality of PVAc adhesivebond of thermally modified wood was lower, which was particularly evident at testing specimens.
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