A novel, environmentally friendly, biomass-based modification technique utilizing carboxymethylation-activated alkali lignin (CAAL) and glutaraldehyde (GA) is proposed to enhance the physical and mechanical properties of poplar and fir wood. Water-soluble CAAL was prepared by modifying alkali lignin (AL) with sodium chloroacetate following low-temperature activation under a NaOH/urea system. AL is a biomass-based material from industrial by-products. As such, it does not rely on fossil resources nor emit volatile compounds that might limit its range of application. The successful preparation of CAAL was demonstrated by Fourier transform infrared spectroscopy (FTIR), ¹H nuclear magnetic resonance spectroscopy (NMR), and ¹³C NMR, and the changes in structure were analyzed by 2D-heteronuclear singular quantum correlation (2D-HSQC), ³¹P NMR, and gel permeation chromatography (GPC). The following characteristics of the modified wood samples were investigated in detail: weight percent gain (WPG), bulking, anti-swelling efficiency (ASE), water absorption rate (WAR), leachability of the modifier, microstructure, and mechanical properties. Water immersion results demonstrated that the CAAL/GA hybrid modifier enhanced ASE to 41.3% and 31.5% for fir and poplar, respectively, at a concentration of 15 wt.%. Furthermore, the WAR of fir was reduced by nearly three times to 30.7%, compared to that of a control sample treated solely with GA. GA-treated samples showed high brittleness, whereas both poplar and fir showed enhanced modulus of rupture and elasticity following treatment with the CAAL/GA hybrid modifier.

提出了一种利用羧甲基化活化碱木质素 (CAAL) 和戊二醛 (GA) 的新型、环保、基于生物质的改性技术，以提高杨木和杉木的物理和机械性能。水溶性 CAAL 是通过在 NaOH/尿素体系下低温活化后用氯乙酸钠改性碱木质素 (AL) 制备的。AL 是一种来自工业副产品的生物质基材料。因此，它不依赖化石资源，也不排放可能限制其应用范围的挥发性化合物。^{通过傅里叶变换红外光谱（FTIR）、 1} H核磁共振光谱（NMR）和¹³证明了CAAL的成功制备。C NMR，并通过二维异核奇异量子关联 (2D-HSQC) 分析结构变化，³¹P NMR 和凝胶渗透色谱法 (GPC)。对改性木材样品的以下特性进行了详细研究：增重百分比 (WPG)、膨松度、抗膨胀效率 (ASE)、吸水率 (WAR)、改性剂的浸出性、微观结构和机械性能。水浸结果表明，CAAL/GA 杂化改性剂在 15 wt.% 的浓度下，将杉木和杨树的 ASE 分别提高到 41.3% 和 31.5%。此外，与仅用 GA 处理的对照样品相比，冷杉的 WAR 降低了近三倍，达到 30.7%。GA 处理的样品显示出高脆性，而杨树和冷杉在使用 CAAL/GA 混合改性剂处理后均显示出增强的断裂模量和弹性。