人工林杨木增强-染色复合改性材的性能

Properties of Strengthening-Dyeing-Combined Modified Plantation Poplar Wood

【目的】探讨人工林杨木增强-染色复合改性方法及改性材性能,为人工林杨木资源的高效开发利用提供技术支持。【方法】将相同质量分数的酸性大红G水溶液、酸性湖蓝A水溶液、酸性大红G和酸性湖蓝A与水溶性树脂型增强改性剂MUF复配得到的增强-染色复合改性剂,分别对人工林杨木进行真空加压浸渍处理,得到D_G、D_A、MUF-D_G和MUF-D_A4种染色改性材,测试其强度、颜色、耐水色牢度等性能。【结果】1)D_A和D_G染色材的质量增加率分别为-1.69%和-0.65%,密度分别为0.352和0.365 g·cm-3;MUF-D_A和MUF-D_G增强-染色复合改性材的质量增加率分别为42.64%和54.27%,密度分别为0.445和0.510 g·cm^(-3)。与D_A染色材相比,MUF-D_A增强-染色复合改性材的密度、抗弯弹性模量、抗弯强度和抗压强度分别提高26.42%,6.76%,17.63%和54.32%;与D_G染色材相比,MUF-D_G增强-染色复合改性材的密度、抗弯弹性模量、抗弯强度和抗压强度分别提高39.73%,8.58%,18.82%和57.18%。2)D_A染色材和MUF-D_A增强-染色复合改性材染色前后的明度指数差(ΔL*)、红绿指数差(Δa*)和黄蓝指数差(Δb*)均为负值,MUF-D_A增强-染色复合改性材的Δa*值更小、ΔL*和Δb*值均更大,蓝色调更明显;D_G染色材和MUF-D_G增强-染色复合改性材染色前后的Δa*为正值、ΔL*和Δb*为负值,MUF-D_G增强-染色复合改性材的Δa*、ΔL*和Δb*值均更大,红色调更明显;MUF-D_A和MUF-D_G增强-染色复合改性材的色饱和度差(ΔC*)均显著大于相应的D_A和D_G染色材。3)D_A和D_G染色材水浸前后的总色差ΔE*分别为12.92和8.30 NBS,MUF-D_A和MUF-D_G增强-染色复合改性材水浸前后的总色差ΔE*分别为5.94和6.93 NBS,增强-染色复合改性材水浸前后颜色溶蚀程度较小。4)D_A和D_G染色材与未处理材的红外光谱图形态基本一致,MUF-D_A和MUF-D_G增强-染色复合改性材与MUF增强改性材的红外光谱图形态基本一致,没有新的吸收峰产生,吸收峰强度也无明显变化。【结论】1)染料的加入对树脂的增强改性作用影响较小,经增强-染色复合改性处理后人工林杨木的力学性能明显提高;2)与纯染色材相比,增强-染色复合改性材的颜色更鲜明饱满,染色效果更好,且酸性大红G与树脂复配染色效果优于酸性湖蓝A;3)与纯染色材相比,增强-染色复合改性材耐水色牢度较好,其中酸性湖蓝A与树脂复配改性材的耐水色牢度提高明显;4)傅里叶红外光谱(FTIR)分析表明,染料与MUF复配染色过程中没有新的基团生成,随树脂固化沉积于木材内部的染料与MUF和木材之间没有产生新的化学结合。

【Objective】In order to provide the technical support for the efficient exploitation and utilization of plantation poplar wood resources,this study investigated the method of strengthening-dyeing-combined modification of plantation poplar wood and the properties of the modified wood.【Method】The acid red G aqueous solution,the acid blue A aqueous solution,and the acid red G and the acid blue A blended individually with water soluble strengthening modifier（i.e.MUF resin）,all of the same dye mass fraction,were used to modify the plantation poplar wood through the vacuumpressure impregnation treatment,and the DA,DG,MUF-DAand MUF-DGdyed wood were obtained respectively.The physical and mechanical properties,color and colorfastness to water of all the dyed wood were measured.【Result】Results showed that：1） The weight percent gain of the DA,DG,MUF-DAand MUF-DGdyed wood were-1.69%,-0.65%,42.64% and 54.27%,and their density were 0.352,0.365,0.445 and 0.510 g·cm^-3,respectively.Compared with those of the DAdyed wood,the density,modulus of elasticity（MOE）,modulus of rupture（MOR）,and compressive strength of the MUF-DAmodified wood increased by 26.42%,6.76%,17.63%,and 54.32% respectively.As compared with those of the DGdyed wood,the density,MOE,MOR,and compressive strength of the MUF-DGmodified wood increased by 39.73%,8.58%,18.82%,and 57.18% respectively.2） The light index difference（ΔL^＊）,greenred index difference（Δa^＊） and yellow-blue index difference（Δb^＊） of the DAand MUF-DAwere all negative,and the MUF-DA＇s Δa^＊was lower,its ΔL^＊and Δb^＊were higher,so its blue tone was more obvious.As for the DGand MUF-DG,the ΔL^＊and Δb^＊were negative and the Δa^＊was positive,and the ΔL^＊,Δa^＊and Δb^＊of the MUF-DGwere all higher,so its red tone was more obvious.The color saturation difference（ΔC^＊） of the MUF-DAand MUF-DGwere much higher than those of the DAand DG.3） The total color difference（ΔE^＊） of the DAand DGafter water erosion test were 12.92 and 8.30 NBS,while those of the MUF-DAand MUF-DGdecreased to 5.94 and 6.93 NBS respectively.4） The IR spectra of the DAand DGdyed wood were similar to that of the untreated wood,and the spectra of the MUF-DAand MUF-DG modified wood were similar to that of the MUF strengthened wood,no new absorption peak was observed and the peak intensity was almost unchanged.【Conclusion】1） The acid dyes had minor effects on the reinforcement function of MUF resin,and their combined modification could significantly improve the density,MOR,MOE,and the compressive strength of plantation poplar wood.2） Compared with the simple dyed wood,the color of strengthening-dyeing combined wood was more vivid and showed better dyeing effect,especially the effect of MUF-DGwas the best.3） The colorfastness to water of the strengthening-dyeing combined wood was better than that of the simple dyed wood,especially the effect of MUF-DAwas the best.4） FTIR analysis showed that no new chemical group generated during the strengthening-dyeing combined modification process,and there was no new chemical bonding produced between the wood components and dye which deposited with MUF resin and fixed in wood.