| Because of their attractive properties such as negligible vapor pressure, non-volatility, wideelectrochemical window and regulatable structure and so on, ionic liquids (ILs) have been extensivelyapplied to many areas as “green†substitutes for conventionally volatile organic solvents. However, somestudies suggested that toxicity of alkyl-imidazolium ILs is similar to some conventionally used organicsolvents, or even higher. Wide application would inevitably result in the loss of them, and resulting inpollutions of eco-environment. While the special properties of ILs made them difficult to be analyzed anddetected. Therefore, it is important to determine trace alkyl-imidazolium ILs in environmental samples.Molecular imprinting has become the topic research of many researchers for the construction of stablepolymeric networks in tailor-made fashion in recent years. Due to its outstanding advantages of goodaffinity, strong specific recognition ability, high selectivity, powerful anti-interference ability, betterstability and reusability, long life and among others, molecular imprinting technology has been wildly usedin many fields such as chromate-graphic separation, solid phase extraction, and chemical sensors and soon.In this paper, three novel surface molecular imprinted polymers(MIP) were prepared by using1-butyl-3-methylimidazolium chloride ILs (C4mimCl),1-ethyl-3-methylimidazolium chloride ILs(C2mimCl) and1-ethyl hydroxyl-3-methylimidazolium chloride ILs (C2OHmimCl) as the template,respectively. The as-prepared imprinting polymers were characterized by various techniques, its staticadsorption properties such as adsorption isotherm, adsorption kinetics and absorption selectivity, dynamicadsorption properties and adsorption properties in environmental water samples were studied in detail. Themain research results are listed as follows:1, The structural properties, toxicity and the present analytical methods were first discussed, then thestudies on the molecular imprinting technique, including the classification, preparation principle, methods,application in solid phase extract, were reviewed. Finally, the target, content and novelty stament have beenintroduced briefly. Here167references were cited.2, Three novel alkyl-imidazolium ILs surface molecular imprinted polymers were prepared. SEM micrographs, BET surface area analysis and (FT-Ir) spectra were selected to characterize the structuralinformation and chemical composition. Interaction between the template molecule and functional monomerwas studied through the changes of UV spectroscopy and1HNMR titration. Accordingly, the possiblemolecular recognition mechanism was also investigated3, The static adsorption performance of the three surface molecularly imprinted polymers was testedby the adsorption isotherms, kinetic curve and selective adsorption experiments. And the results suggestedthat the molecularly imprinted polymer had a significantly higher adsorption capacity for the templatecompared with the corresponding non-imprinted polymer. The experimental data of adsorption isothermfitted to the Langmuir and the Langmuir-Freundlich model very well, and the maximum adsorptioncapacity, the total number of binding sites and the mean association constant were calculated accordingly.The adsorption kinetic experiments suggested that three imprinted polymers achieved the adsorptionequilibrium within40min, and the adsorption process could be described by pseudo-second order kinetics.Results from the adsorption selectivity experiments showed that this three surface molecularly imprintedpolymers can separate and extract the template selectively from the complex matrixes and structuralanalogs.4, The solid phase extraction columns were prepared by using C4mimClMIP and C2mimClMIP as thesolid phase sorbents. Various parameters were optimized for the solid phase extraction columns, such asloading volumn, flow rate, eluent solvent and so on. Under the optimized column parameters, solid phaseextraction column coupled with HPLC was used for the evaluation of the separation and extractionproperties for alkyl-imidazolium ionic liquids. The results showed that the two solid phase extractioncolumns can separate and extract the template IL and its structural analogs from complex matrix, and whenthey were applied to the determination of the IL in environmental water samples, the recoveries was i over90%for the two ILs, and exhibited excellent practical properties.5, Summarized the main research results and conclusions of this thesis; point out the problems need tobe resolved in this topic and present molecular imprinted technique; and put forward my views andsuggestions for the future work of the this technique. |
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