蒸汽热处理红锥木材颜色变化及其材性预测  

Color Change and Timber Property Prediction of Castanopsis hystrix Wood After Steam Heat Treatment

作　　者：李腊梅 谢桂军[1] 李兴伟[1] 曹永建[1] 李怡欣[1] 李万菊 LI Lamei;XIE Guijun;LI Xingwei;CAO Yongjian;LI Yixin;LI Wanju(Guangdong Academy of Forestry,Guangdong Provincial Key Laboratory of Silviculture,Protection and Utilization,Guangzhou 510520,China)

机构地区：[1]广东省林业科学研究院、广东省森林培育与保护利用重点实验室,广州510520

出　　处：《森林工程》2023年第5期92-104,共13页Forest Engineering

基　　金：广东省林业科技创新项目(2018KJCX006)。

摘　　要：木材热处理技术作为一种环境友好的木材物理改性方法,能够有效改善木材材色、提高木材尺寸稳定性和生物耐久性,被广泛应用于木材的功能性改良。以红锥(Castanopsis hystrix)木材为研究对象,采用水蒸气为加热介质,在温度150~210℃条件下进行1.5~4.5 h的热处理,研究不同热处理条件下红锥木材的颜色变化,并探讨颜色与其尺寸稳定性、力学性能和生物耐久性间的相关性。结果表明,热处理红锥木材的明度指数(L^(*))降低,红绿指数(a^(*))和黄蓝指数(b^(*))缓慢升高,明度差(ΔL^(*))、总色差(ΔE^(*))逐渐增大,热处理后红锥木材的颜色由原色逐步过渡到深色;干缩率和湿胀率最大降幅分别为55.7%和69.7%,尺寸稳定性明显改善;抗弯强度和弹性模量分别降低3.1%~30.2%和3.7%~20.7%,防白蚁性能和耐腐等级未能得到改善;在试验的温度和时间范围内,热处理红锥木材颜色变化与白蚁蚁蛀后的木材失重率、蚁蛀后白蚁存活率、褐腐菌和白腐菌侵害后的木材失重率存在二阶抛物线关系,与其尺寸稳定性和抗弯性能之间不存在明确相关性。因此,通过颜色变化来预测和评估热处理后红锥木材的抗生物耐久性是可行的。As an environmentally friendly physical modification of wood,wood heat treatment technology can effectively improve wood color,dimensional stability and biological durability of wood,so it is widely used in the functional improvement of wood.In this study,Castanopsis hystrix wood was used as the research object,water vapor was used as the heating medium and the wood was heat treated for 1.5-4.5 h under the temperature of 150-210℃.The color changes of Castanopsis hystrix wood under different hear treatment conditions were studied,and the correlation between color and dimensional stability,mechanical properties and biological durability was also discussed.The results showed that the lightness index L^(*)decreased,the red green index a^(*)and the yellow blue index b^(*)increased slowly,and the lightness differenceΔL^(*)and the total color differenceΔE^(*)increased gradually,indicating that the color of heat treated Castanopsis hystrix wood gradually changed from primary color to dark color.The maximum reduction of dry shrinkage rate and wet expansion rate was 55.7%and 69.7%,respectively,indicating the dimensional stability was obviously improved.The flexural strength and elastic modulus were decreased by 3.1%-30.2%and 3.7%-20.7%,respectively.The termite resistance and rot resistance grade were not improved.In the temperature and time range involved in this experiment,there was a second-order parabolic relationship between the color change of heat-treated wood and the weight loss rate of termite-eaten wood,the survival rate of termite,and the weight loss rate of brown rot wood and white rot wood.However,the correlation between the color change of heat-treated Castanopsis hystrix wood and dimensional stability and bending resistance was unclear.Therefore,it is feasible to predict and evaluate the anti-biological durability of heat treated Castanopsis hystrix wood by color change.

关 键 词：蒸汽热处理 CIE L^(*)a^(*)b^(*)(国际通用的色彩表示标准) 红锥木材 理化性能 力学性能 

分 类 号：S781.2[农业科学—木材科学与技术] S781.3[农业科学—林学] S781.6