Modification and Characterization of Hemp and Sisal Fibers

摘要

这项工作是探讨提高天然纤维与基体的相容性的聚合物溶液中浸渍的纤维表面处理技术的有效性.大麻和剑麻纤维通过比较乙酰化聚合物涂层处理，碱/乙酰化和硅烷化。不同的分析技术被用于检査的表面处理的影响，包括傅立叶变换红外光谱(FTIR)，扫描电子显微镜(SEM),X-射线光电子能谱(XPS)，X-射线衍射(XRD)，和热重分析(TGA)在氮气和空气。红外光谱表明，乙酰化结合碱化LED到最高的半纤维素和木质素去除所有处理过的纤维两种纤维在聚合物涂层，由于羰基的作用，LED峰值在1736厘米左右。处理后纤维的SEM照片显示出清洁表面，那是由于其经过了去除蜡状物质和木质素的过程处理。热稳定处理后纤维的基础上增加了TGA结果除碱化/乙酰化纤维。乙酰化纤维有最低的水分含量，从而表明，乙酰化是一个减少天然纤维的亲水性的有效技术。在比较中，其它处理方法对聚合物涂层并没相同效果。%This work is to investigate the effectiveness of the surface treatment technique of fiber impregnation in polymer solution in improving compatibility of natural fibers with matrix. Hemp and sisal fibers were treated through polymer coating in comparison to acetylation, alkalization/acetylation, and silanization. Different analytical techniques were employed to examine effect of surface treatment, including Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy ,(XPS), X-ray diffraction (XRD), and thermogravimetric analysis (TGA) in nitrogen and air. FTIR showed acetylation combined with alkalization led to the highest hemicellulose and lignin removal among all treated fibers for both fibers, while polymer coating led to an increase at peak around 1, 736 cm~(-1) due to the carbonyl group. SEM micrographs of treated fibers showed cleaner surfaces due to removal of waxy substances and lignin during treatments. Thermal stability of treated fibers increased based on TGA results except for the alkalized/acetylated fiber. Acetylated fibers had the lowest moisture content, thus demonstrating that acetylation is an effective technique to reduce the hydrophilic tendency of natural fibers. In comparison, polymer coating was not as effective as other treatment methods.