Synthesis And Properties Of Metal Ion Imprinted Polymers

Molecularly imprinted polymer (MIP) is a recently developed functional polymer having molecular recognition ability and it can be used widely in affinity chromatography, solid-phase extraction, sensors, biomimetic enzyme and antibody. Compared with biomolecules, MIPs have the advantages of high stability over a wide range of conditions (high temperature, high pressure, organic solvents, strong acidic or basic solutions, etc.) and low cost. The main purposes of this dissertation are synthesis MIPs having high affinity and selectivity, study on the nature of the molecular recognition of MIP and the application of MIP on solid-phase extraction and separation, and the dissertation was composed of four chapters, as follows:1. Exordium described the basic theory of MIP, the method of preparation of MIP and development of application.2. Mercury is one of the most toxic heavy metal elements, Therefore, the development of highly selective adsorbents for mercury ion is of great interest. In this chapter, a type of new Hg(II) ion-imprinted sorbent was prepared, for the first time, by a hierarchically double-imprinting method with both mercury ions and surfactant micelles (cetyltrimethylammonium bromide) as templates, N-[3-(trimethoxysilyl)propyl]ethylenediamine as functional monomer, and tetraethoxysilane as cross-linking agent. The characteristic of these sorbents was evaluated by infrared spectra, and the thermal stability by simultaneous thermal analysis apparatus. The influences of molar ratio of functional monomer to cross-linking agent and the acidity of the solution on their adsorption capacities were also studied by the static-adsorption method. In addition, their adsorption kinetics, selective adsorption abilities and reutilization were also investigated. 3. A new Hg(II)-imprinted thiol-functionalized silica gel sorbent, prepared by combining a surface molecular imprinting technique with a sol-gel process, for selective separation and preconcentration of Hg(II). The characteristic of these sorbents was evaluated by infrared (IR) spectra, and the thermal stability by simultaneous thermal analysis apparatus. The effect of the solution acidity on their adsorption capacities was also studied by the static-adsorption method. In addition, the adsorption kinetics, adsorption selectivity and reutilization were also investigated. Finally, the new sorbents were successfully applied to the separation and determination of the trace Hg(II) in real water samples and those spiked with standards.4. A new Cu(II)-imprinted thiol-functionalized silica gel sorbent, prepared by combining a surface molecular imprinting technique with a sol-gel process, for selective separation and preconcentration of Cu(II). The complex was formed between Cu(II) and MPS, and then cohydrolyz-ed and co-condensed with the activated silica gel. Thus, the activated silica gel surface was grafted with the complex of Cu(II) and MPS rather than just free MPS. After the remnant MPS and Cu(II) were removed by ethanol and HC1, respectively, the imprinted functionalized silica gel sorbent containing tailor-made cavities for Cu(II) was formed.