微米级单分散二氧化硅微球的制备改性及其在液相色谱中的应用

发布时间：2018-04-07 17:09

本文选题：二氧化硅微球　切入点：单分散性　出处：《青岛大学》2015年硕士论文

【摘要】：单分散二氧化硅微球在抗反射涂层材料、生物医药、催化剂载体、光子晶体和色谱填料等方面有广泛的应用。微球的尺寸、单分散性和表面性能对其应用有重要的影响,学术界和工业界对于尺寸可控、形貌优良、单分散性好的二氧化硅微球的需求在持续的增加。由于微球的性能随着粒径尺寸分布的变化而变化,单分散微球的制备方法也逐渐引起人们的关注。制备单分散二氧化硅颗粒的方法很多,如液相法和气相法等,其中最经典的方法是溶胶-凝胶法(也称St?ber法),但是St?ber法通常用于合成亚微米级的单分散二氧化硅微球,而对于粒径较大二氧化硅微球的合成存在粒径难以控制、单分散性差等诸多问题。本文通过改进溶胶-凝胶法,即将正硅酸乙酯溶解在乙醇中,通过连续加料的方式滴加到含有氯化钾、水、氨水和乙醇的溶液中,成功制备了粒径1~2μm的单分散二氧化硅微球,研究了不同反应条件对所生成二氧化硅微球粒径大小和单分散性的影响。结果表明,随着氨水量的增大,反应温度的降低,滴加速度的加快,TEOS浓度变小,二氧化硅微球粒径减小,单分散性变好。将二氧化硅微球表面修饰后可以进一步提高性能,扩大其应用领域。一般的修饰方法分为物理修饰、化学修饰和物理化学同步修饰。本文中通过化学修饰的方法,将十八烷基三氯硅烷成功的修饰到了二氧化硅微球的表面,并成功的运用到了色谱分离富勒烯中,由于微球粒径小、单分散性好、柱效高,利用长度仅为5 cm的不锈钢短柱便取得了良好的富勒烯分离效果,优于柱长为15 cm,二氧化硅填料粒径为5μm的商业化C18色谱柱。
[Abstract]:Monodisperse silica microspheres are widely used in antireflective coating materials, biomedicine, catalyst carriers, photonic crystals and chromatographic fillers.The size, monodispersity and surface properties of microspheres have an important impact on their applications. The demand for silica microspheres with controllable size, good morphology and good monodispersity is increasing in academia and industry.As the properties of microspheres vary with the size distribution of particle size, the preparation of monodisperse microspheres has attracted more and more attention.There are many methods for preparing monodisperse silica particles, such as liquid phase method and gas phase method. The most classical method is sol-gel method (also called St?ber method), but St?ber method is usually used to synthesize monodisperse silica microspheres of submicron size.However, there are many problems in the synthesis of larger silica microspheres, such as difficult to control the particle size, poor monodispersity and so on.In this paper, by improving the sol-gel method, ethyl orthosilicate was dissolved in ethanol and dropped into the solution containing potassium chloride, water, ammonia and ethanol. The monodisperse silica microspheres with the diameter of 1 渭 m were successfully prepared.The effects of different reaction conditions on the size and monodispersity of silica microspheres were studied.The results show that with the increase of ammonia content, the reaction temperature decreases, the droplet acceleration accelerates, the concentration of TEOS decreases, the particle size of silica microspheres decreases, and the monodispersity becomes better.The surface modification of silica microspheres can further improve its performance and expand its application field.General modification methods can be divided into physical modification, chemical modification and physicochemical synchronous modification.In this paper, octadecyl trichlorosilane was successfully modified to the surface of silica microspheres by chemical modification, and successfully applied to chromatographic separation of fullerenes.A good separation effect of fullerene was obtained by using a stainless steel short column with a length of only 5 cm, which was superior to a commercial C 18 column with a column length of 15 cm and a silica filler size of 5 渭 m.
【学位授予单位】：青岛大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TQ127.2;O657.72

【相似文献】