The Preparation Of Carbon Nanomaterials/Polymer Composites And Fluorescent Polymeric Nanoprobes Based On Mussel Biomimetic Chemistry

Research on carbon nanocomposites is quite important to the development of science and evolution of society. In recent years, carbon nanomaterials/polymer composites have inspired growing interesting in chemical and materials industry as their outstanding mechanical, electrical and thermal performance. Although great achievements have been made, most of present methods for fabrication of carbon nanomaterials based nanocomposites still have some drawbacks. For example, covalent methods relied on the functional groups what carbon nanomaterials just lacked. On the other hand, covalent methods will destroy the structure of carbon nanomaterials. Non-covalent methods have another trouble from the weak strength of carbon nanomaterials and polymers. Therefore, it is imperative for the development of high-efficient carbon nanomaterials/polymer composites to explore new materials and create new methods. Mussel inspired chemistry, a green strategy, has been developed in recent years. And mussel inspired chemistry can be applied to modify the surface of almost any type of materials. To date, only very limited studies have used mussel inspired chemistry for the preparation of carbon nanomaterials/polymer composites.The main contents of this thesis were divided into three parts, which correspond to the preparation of carbon nanotube/polymer composites (chapter two), graphene oxide (GO)/poly(N-isopropylacrylamide) composites and GO/polyacrylic acid based on mussel inspired chemistry (chapter three) and preparation of fluorescent polymer based on mussel inspired chemistry (chapter four). Details are as fellow:(1) The second chapter is the preparation of carbon nanotube composites based on mussel inspired chemistry. As the structural perporties of carbon nanotube, it was coated by the film of polydopamine combing the self-polymerization of dopamine under alkaline environment. Then, the reversible addition-fragmentation chain transfer polymerization (RAFT) agents was improted onto the surface of carbon nanotube, and acts the chain transfer agent for the next reaction. Finally, carbon nanotube/polyethylene glycol methyl ether methacrylate composites were got by RAFT polymerization, and possessed outstanding dispersion and stability.(2) The third chapter is the preparation of GO composites through combination of mussel inspired chemistry and Michael addition reaction. Firstly, GO was produced from graphite powder via Hummers methods. Later, GO was then modified with polydopamine through self polymerization of dopamine. While poly(N-isopropylacrylamide) and polyacrylic acid were prepared by RAFT polymerization. To obtain the GO based composites, GO-polydopamine reacted with poly(N-isopropylacrylamide) and polyacrylic acid, respectively. On the basis, the dispersion and stability of the composites were studied. The results showed GO/poly(N-isopropylacrylamide) composites and GO/polyacrylic acid not only owned excellent dispersion and stability but also temperature sensitivity and pH sensitivity, respectively.(3) Chapter four was the preparation of fluorescent polymer based on mussel inspired chemistry. First, polymers pendented with dopamine were prepared via combination of RAFT polymerization and multicomponent reaction. Then, the polymers reacted with polyethyleneimine, and get the fluorescent polymer nanoparticles. This is a novel strategy for fabrication of fluorescent polymers from nonfluorescence dopamine and polyamino compounds through self polymerization, which can be occurred in aqueous solution, under air atmosphere, at room temperature and without any metal catalysts. Our results demonstrated that these fluorescent polymers showed strong fluorescence, high water dispersibility, good biocompatibility and high photostability, making them promising for biomedical applications.