剑麻纤维素微晶的制备与表征

通过对剑麻纤维进行预处理、碱处理、酸解等步骤制备剑麻纤维素微晶,采用红外光谱(FT-IR)、X射线衍射(XRD)、偏光显微镜(POM)、扫描电镜(SEM)、差示扫描量热(DSC)和热重分析(TGA)等方法对产物进行了表征。红外谱图分析表明,所制备的剑麻纤维素微晶的主要成分为纤维素;而XRD、POM和SEM结果表明,剑麻纤维素微晶以纤维素Ⅰ的形式存在,长度尺寸在50μm~150μm之间,直径10μm左右;DSC和TGA热分析结果表明,剑麻纤维素微晶在323.7℃处有一尖锐的结晶熔融吸热峰,其初始热分解温度达到337℃,比普通剑麻纤维的初始热分解温度提高60℃,并且其在700℃时的最后残留物仅为0.05%。

Extraction and Characterization of Cellulose Microcrystal from Sisal Fibers

Cellulose microcrystal was extracted from sisal fibers by means of chemical procedures such as alkaline extraction and acid hydrolysis.The final cellulose microcrystal was characterized by Fourier transform infrared spectra(FT-IR),X-ray diffraction(XRD),polarized optical microscopy,scanning electron microscope(SEM),differential scanning calorimetry(DSC) and thermogravimetric analysis(TGA).The results prove that the obtained cellulose microcrystal with diameter of 10μm and length of 50μm~150μm is present in the form of cellulose I.A sharp endothermic peak at 323.7 ℃ could be seen in DSC thermograms.The result of TGA shows that it has a sharp mass loss starting at 337 ℃ higher than sisal fibers starting at 277 ℃,and is almost completely pyrolyzed at 700 ℃ with a residual mass of 0.05%.