Department of Chemistry, Wuhan University, Wuhan 430072, China.
J Chromatogr A. 2010 Sep 17;1217(38):5922-9. doi: 10.1016/j.chroma.2010.07.026. Epub 2010 Jul 22.
Regenerated cellulose microspheres (RCM) with different diameters were prepared from cellulose solution using 7 wt% NaOH/12 wt% urea aqueous solvent pre-cooled to -12 degrees C by the sol-gel transition method via a "green" process. By varying the hydrophile-lipophile balance, the amount of the surfactants, the proportion of the water to the oil phase and the stirring speed, the mean diameter of the cellulose microsphere with nanoscale pore size could be controlled easily from 5 microm to 1mm. The structure and physicochemical properties of the microspheres were characterized by FT-IR spectroscopy, scanning electron microscopy, X-ray diffraction, mercury intrusion-porosimetry and particle size analyzer. The RCM microspheres exhibited spherical shape with the cellulose II structure. A preparative size-exclusion chromatography (SEC) column packed with the cellulose microspheres was used for the fractionation of a polyethylene oxide (PEO) in water, which indicated high efficiency for the fractionations and a large daily throughput of 4 g. Moreover, they had good adsorption capacity to dye particles through physical interaction. The cellulose microspheres would have potential applications in the fields of purification, separation and fractionation of polymers as chromatography packing and adsorbent both at laboratory and industrial scale.
采用溶胶-凝胶转变法，以 7wt%NaOH/12wt%尿素水溶液为溶剂，将纤维素溶液预冷却至-12°C，制备出不同粒径的再生纤维素微球（RCM）。通过改变亲水亲油平衡、表面活性剂用量、水油相比例和搅拌速度，可以轻松控制具有纳米级孔径的纤维素微球的平均粒径从 5 微米到 1 毫米。采用傅里叶变换红外光谱（FT-IR）、扫描电子显微镜（SEM）、X 射线衍射（XRD）、压汞孔隙率和粒径分析仪对微球的结构和理化性质进行了表征。RCM 微球呈球形，具有纤维素 II 结构。用纤维素微球填充的制备尺寸排阻色谱（SEC）柱用于在水中对聚环氧乙烷（PEO）进行分级，这表明该柱对分级具有高效性，每日的处理量高达 4g。此外，它们通过物理相互作用对染料颗粒具有良好的吸附能力。纤维素微球在实验室和工业规模的色谱填料和吸附剂方面，在聚合物的纯化、分离和分级等领域具有潜在的应用前景。
