高温热改性橡胶木的生物耐久性

以水蒸气作为保护气体,在170,185,200和215℃的条件下分别热处理橡胶木3h,对热改性橡胶木的生物耐久性进行研究.结果显示:高温热改性可提高橡胶木的耐腐性,其改善效果随着处理温度的升高而提高,当处理温度为185℃或更低温度时,改善效果不明显.215℃处理3h后,褐腐(密黏褶菌)质量损失率由51.6％降至21.6％,白腐(采绒革盖菌)质量损失率由27.6％降至6.8％.选用烟曲霉、哈茨木霉、产紫青霉和可可球二孢进行防霉试验,结果显示热改性橡胶木的防霉性能与对照相比没有明显的改善；经涂饰后,热改性试材的防霉性能优于未处理材.野外耐久性试验结果显示,高温热改性不能提高橡胶木的防白蚁性能.

Biological Durability of Heat-Treated Rubber Wood

In this study,the durability of rubber wood(Hevea brasiliensis) which was thermally treated at 170,185,200,and 215 ℃ for 3 h respectively was investigated.The results showed that the durability of heat-treated rubber wood was improved,and the improvement became more obvious with the increase of the treating temperature.When treated at 185 ℃ or lower temperature,the decay resistance of treated wood had no significant improvement.The lowest weight losses were 21.6% and 6.8% after attack by brown rot fungi(Gloeophyllum trabeum) and white rot fungi(Coriolus versicolor) respectively,which were reached by the specimens treated at 215 ℃.Their resistance to mold fungi was not improved,but the heat-treated wood performed better than untreated wood when both were painted.In field test,the heat-treated specimens exhibited no advantage in termite resistance compared to untreated.