柠檬酸与蔗糖改性杉木的物理性能

Physical Properties of Chinese Fir Wood Modified with the Mixing Agent of Citric Acid and Sucrose

采用不同质量浓度的柠檬酸与蔗糖复配改性剂处理人工林杉木(Cunninghamia lanceolata(Lamb.)Hook),系统地评价了改性处理对杉木关键物理性能的影响。结果表明:随着改性剂质量浓度的增加,杉木密度增加、孔隙率降低的同时,木材表面明度下降、色差增加,木材颜色由未处理杉木的浅黄色向处理后的棕褐色转变。流失性能测试表明,经水浸泡清洗后单纯的蔗糖处理木材的流失率近96%,而柠檬酸和蔗糖复配改性处理杉木的流失率则降至21%,表明柠檬酸对蔗糖的交联固着效果良好。尺寸稳定性分析表明,蔗糖本身处理并不能改善木材的尺寸稳定性;与未处理木材相比,柠檬酸与蔗糖复配改性剂处理杉木的增容率可达6%、干缩率下降55%以上,尺寸稳定性实质性增强。综上所述,柠檬酸作为交联剂能够有效的将蔗糖固定在木材内,改善杉木尺寸稳定性等关键材性。复配改性剂具有环境友好性和来源可持续性。

Citric acid(CA)and sucrose(SC)were mixed and used to treat Chinese fir(Cunninghamia lanceolata(Lamb.)Hook)wood at various concentrations.The treating effects on physical properties of wood were evaluated systematically.The treated wood indicated an increase in density and a decrease in pore ratio with increasing the concentration of modifying agent.The lightness was decreased and color difference decrease for the treated wood compared to the untreated one.The surface color of the wood changed from light yellow to dark brown after the treatments.By leaching test,96%sucrose were washed away for wood treated with sucrose alone;however,wood treated with CA and SC exhibited a leaching ratio of 21%,suggesting a proper fixation of chemicals in wood.Treatment with CA/SC caused a cell wall bulking up to 6%and the shrinkage of wood in the drying process decreased more than 55%,suggesting a substantial improvement in dimensional stability.The results demonstrates that CA as a cross-linker can efficiently react with sucrose and wood,thereby fixing the agent and improve some of the crucial properties such as dimensional stability of wood.The modifying agent is eco-friendly and sustainable.