Preparation, Characterization And Application Of Functionalized Oxidized Graphene Hydroxyethyl Methacrylate

As a new carbon materials, compared to the conventional carbon materials, the chemical and physical properties of graphene have unparalleled. It is the most ideal materials with two-dimensional structure, with only one carbon atom thick, its unique structure determines numerous outstanding performance, such as large specific surface area, excellent electrical conductivity, thermal conductivity, anomalous quantum Holzer effect, excellent mechanical, optical performance make it show a broad application prospect in the separation materials, electronic devices, energy storage materials, sensors, biomedicine fields. Graphene oxide can be regarded as graphene derivatives, which is distinct from the graphene, with a large number of reactive oxygen groups can be modified using a variety of chemical reaction by these active oxygen groups. After being modified, the graphene oxide not only can be improved the dispersibility in the solution, but also can be prepared composite materials with special properties.The surface molecular imprinting technique is different from the traditional molecular imprinting technique, which can avoid many shortcomings of traditional imprinted polymers, such as:nonuniformity of particle size, deep embedding of the template molecule, difficulties of elution, the easily destruction of imprinted sites with grinding and the inherent defects of low adsorption amount. Its binding sites are exposed on the surface of the matrix, the template molecules can be recombined more easily, which significantly improves the mass transfer rate. At present, small molecular imprinting technology is increasingly mature, but it is particularly difficult for the imprinting of biological macromolecules, such as protein, due to the larger molecular size, the complex3D structure and fragile stability which make the imprinting protein still very difficult. To some extent, these problems can be solved in the process of preparation of proteins molecularly imprinted polymers using surface imprinting method.This thesis mainly consists of four parts:1. Review:In this chapter, the physical and chemical properties, preparation method and applications of graphene and graphene oxide were briefly elaborated. The basic principle, the preparation method and the application of molecular imprinting technique in various fields made a simple introduction. 2. Preparation and characterization of functional graphene oxide:Graphene oxide was prepared by Hummers method, its surface can be modified by2-Hydroxyethyl methacrylate, this work not only prepared the functional graphene oxide with lamella number less but also improved the dispersibility in the solution which preventing the reunion into pieces again. The morphology of functional graphite oxide was tested by SEM and TEM, the functional material through modification showed the single layered compared with graphene oxide which was layered reunion. The infrared detection proved that2-Hydroxyethyl methacrylate was successfully bonded to the surface of graphene oxide.3. Functional graphene oxide adsorbs dopamine:the results of adsorption showed that when using graphene oxide and functional graphene oxide as the matrix at the same conditions, the adsorption capacity of dopamine using functional graphene oxide was obviously higher than the former. Based on the adsorption isothermand the Scatchard equation the maximum adsorption capacity can reach58.5mg/g. After recycling5times, functionalized graphene oxide showed well stability.4. Preparation and characterization of lysozyme molecular imprinting polymer:in this work, lysozyme surface molecularly imprinted microspheres were prepared using hydroxyethyl methacrylate modified PGMA/EDMA microspheres as the carrier, lysozyme as template molecule, acrylamide as functional monomers. The surface morphology of microspheres was observed by SEM, infrared detection of changes of functional groups on the surface of the microspheres in different synthesized stages. Chromatography experiment verified that the polymer has specially selectivity to lysozyme. In addition, the experiment investigated the influence of the pH of the mobile phase to the retention behavior of lysozyme on polymer.