热处理木材提取物微胶囊防腐剂对杨木耐腐性影响研究

Effect of Heat-treated Wood Extract Microcapsule Preservative on the Decay Resistance of Poplar

在不同pH值的反应条件下,通过正硅酸四乙酯的水解缩合得到二氧化硅;运用溶胶凝胶法制备几种热处理木材提取物/二氧化硅微胶囊,并采用真空-加压浸渍改性杨木。通过流失试验和耐腐试验,研究微胶囊对改性杨木耐腐性的影响;通过酶活性试验探究了微胶囊的抑菌机理。结果表明:热处理木材提取物/二氧化硅微胶囊木材防腐剂可以提高木材的抗流失性和耐腐性;微胶囊抑菌成分主要通过影响白腐菌中木质素酶(锰过氧化物酶、漆酶)、纤维素酶(外切纤维素酶、β-葡萄糖苷酶)、半纤维素酶活性达到阻碍白腐菌生长的目的;微胶囊仅对褐腐菌中纤维素酶(内切纤维素酶)活性有抑制作用。

Under the reaction conditions of different pH values,silica was obtained by hydrolysis and condensation of tetraethyl orthosilicate.Several heat-treated poplar extracts/silica microcapsules were prepared by sol-gel method.The prepared microcapsule emulsion was impregnated into wood by vacuum-pressure impregnation.The effect of microcapsules on the decay resistance of modified poplar was verified by the leaching resistance test and the decay resistance test.The antifungal mechanism of microcapsules was explored by enzyme activity test.The results showed that heat-treated poplar wood extract/silica microcapsule wood preservative could improve the leaching resistance and the decay resistance of wood.Microcapsules inhibited the growth of white rot bacteria by affecting lignin(manganese peroxidase,laccase),cellulase(exocellulase,β-glucosidase) and hemicellulase activities in white rot bacteria.Microcapsules only inhibited the activity of cellulase(endonuclease cellulase) in brown rot bacteria.