压缩致密化阻燃木材的燃烧特性和成炭行为研究*

为增强木材的阻燃性能，采用压缩致密化工艺制备致密化阻燃木材，并对其燃烧特性与成炭行为进行研究。结果表明:压缩致密化工艺能促进木材在燃烧过程中形成更多的芳香结构以增强炭层的致密性和隔热性，进而有效阻隔热量和氧气进入木材内部，使致密化木材表现出良好的阻燃性和自熄性。压缩致密化木材的阻燃和隔热性能与去木质化程度密切相关，并随去木质化程度的增加呈先提高后下降的趋势。经过24 h去木质素处理后的致密化木材的极限氧指数增加到39.5%并达到UL94 V-0级，总释放热和2 400 s背面平衡温度相比于未去木质素的致密化木材分别下降了25.8%和21.4%，表现出最佳的阻燃和隔热性能。

Study on combustion characteristics and char formation behavior of compressed densifying flame-retardant wood

In order to improve the flame retardancy of wood,the compressed densifying technology was applied to prepare the densifying flame-retardant wood,and its combustion characteristics and char formation behavior were studied.The results showed that the compressed densifying technology could promote the formation of more aromatic structures in the combustion process of wood to enhance the compactness and thermal insulation of char layer,thus effectively block the heat and oxygen into the wood interior,which made the densifying wood present good flame retardancy and self-extinguishing property.The flame retardancy and thermal insulation property of compressed densifying wood were closely related to the degree of delignification,and presented a trend of increasing first and then decreasing with the increase of the degree of delignification.The limiting oxygen index of the densifying wood after 24 h delignification increased to 39.5% and reached UL94 V-0 rating,and compared with the densifying wood without delignification,the total heat release and the backside equilibrium temperature at 2 400 s decreased by 25.8% and 21.4%,respectively,showing the best flame retardancy and thermal insulation property.