碱蚀改善毛竹条孔隙及染液渗透性研究  

Improvement of porosity and dye permeability of moso bamboo splints by alkali etching

作　　者：庞晓娜 杨祥 李贤军[1] 曹敏 杨喜[1] PANG Xiaona;YANG Xiang;LI Xianjun;CAO Min;YANG Xi(Central South University of Forestry and Technology,Changsha 410004,China)

机构地区：[1]中南林业科技大学,长沙410004

出　　处：《林业工程学报》2021年第6期44-50,共7页Journal of Forestry Engineering

基　　金：国家自然科学基金(31901375)。

摘　　要：竹材的液体渗透性对竹资源增值高效利用和竹材功能多样性发展具有重要促进意义。采用混碱溶液对毛竹条进行改性处理,通过单因素试验法研究碱蚀时间和干燥方式对竹材染液渗透效果的影响,运用傅里叶红外光谱仪、扫描电镜和压汞仪表征了碱蚀作用下毛竹条的化学组分、微观形貌和孔隙结构等的变化,初步阐明了碱蚀改善毛竹条孔隙及液体渗透性的机理。结果表明,碱蚀时间对毛竹条质量损失率和染液渗透效果等有显著影响。其中碱蚀2和3 h时竹材质量损失较为明显,即孔隙率增加较为明显。在碱蚀2 h条件下,竹条形态较完整,染液渗透效果较好且质量损失率相对碱蚀3 h更小。碱蚀处理可以使竹条内部大部分木质素和半纤维素溶解析出,破坏细胞间弱相胞间层,使部分纤维和薄壁细胞间产生裂缝,150μm左右及以上的大尺寸微米级孔隙明显增多,进而增加染液渗透通道,缩短渗透路径并增强渗透效率,实现毛竹条的全尺寸均匀渗透。Bamboo has drawbacks of poor liquid permeability,single texture color and easy mildew,which can be addressed by utilizing modification agents.To promote the efficient utilization and develop the functional diversity of bamboo,this paper proposed a novel treatment technique of alkali corrosion to modify the chemical composition,microstructure,pore structure and liquid permeability of Phyllostachys pubescens.The moso bamboo splints were modified by mixed alkaline solution in this study.The effects of alkali etching time and drying method on the penetration of bamboo dyeing liquor were studied using a single factor experiment.The changes of chemical composition,micro morphology and pore structure of moso bamboo splints under alkali etching were characterized by the Fourier transform infrared spectroscopy,scanning electron microscope and mercury intrusion instrument.The mechanism of the alkali etching on improving the porosity and liquid permeability of bamboo splints was preliminarily investigated.Compared with drying methods,the time of alkali etching had more significant effect on the mass loss rate and the permeation effect of dye.The results showed that the mass loss rate of bamboo splints was more significant at 2 and 3 h during the alkali etching,that was,the porosity increased more significantly.When the alkali etching time was 2 h,the shape of bamboo splint was almost unchanged,the dye penetration effect was increased,and the mass loss rate was smaller than that under 3 h alkali etching.At this time,the mass gain rate of freeze-dried bamboo splints was significantly higher than that of dried bamboo splints,and the mass gain rate gradually decreased with the extension of dyeing time.The alkali treatment could reduce the intensity of the infrared characteristic absorption peaks of lignin and hemicellulose in bamboo splints,which made most of the lignin and hemicellulose being dissolved and destroyed the weak phase intercellular layer,created some cracks between fibers and parenchyma cells,increased the interna

关 键 词：碱蚀 毛竹条 弱相结构 孔隙 液体渗透性 

分 类 号：S781.9[农业科学—木材科学与技术]