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This thesis proposed a new type of positively charged membrane preparation method and explore various film deposition conditions on membrane performance, dimensional infrared analysis of the the membrane liquid absorbent process. Charged membrane because of its unique electrostatic adsorption and repulsion makes large aperture membrane adsorption separation smaller particle size of the material as possible. Further, since the introduction of charged groups in the membrane, the hydrophilicity of the film has been strengthened, and thus the increase in the amount of membrane permeable, the stain resistance also significantly enhanced. Also due to electrostatic interactions between the film and the solution, the osmotic pressure of the solution is reduced, and therefore suitable for low pressure operation. So, has the neutral film does not have the advantage of and uses charged membrane permeable, anti-pollution, as well as select through such. However, due to the commercial interests of the trend, the current study focused on the negative charge of the Dutch charge positive charge are few, but the the film positively charged protein separation, cathodic electrophoretic paint recycling, and the removal of the bacterial neomycin has of charged membranes incomparable and alternative role. The positively charged membrane preparation requires the use of highly toxic carcinogen chloromethyl ether, preparation difficulty and cost, so far at home and abroad did not the similar commodities film appears, researchers rarely. Our group previously used of trimethylamine in situ amination phase conversion prepared positively charged membrane, this paper is used a novel of amination agent - triethanolamine to prepare a positively charged membrane, we used amination agent triethanolamine containing three alcoholic hydroxyl groups, can significantly change the hydrophilicity and stain resistance of the film, In addition, in the preparation process of the film, using N-methyl pyrrolidone / water as the solvent / non-solvent system, chlorobenzene / cleaner than the previous Yi obtained. This thesis discussed in detail the parameters of the film formation, such as the polymer concentration, the proportion of the polymer with triethanolamine, the different types of amination reagent, the temperature of the coagulation bath, the evaporation time and the relative humidity and other factors impact on membrane performance and its structure. In addition, we use two-dimensional infrared detailed analysis of the casting solution in the evaporation process of water absorption. This thesis includes five chapters the first chapter is an introduction, a brief introduction to the history of the development, application and classification of the separation membrane. After the introduction of the common characterization methods of the charged membrane several preparation methods and the charged membrane and the positively charged film Research summarized immersion precipitation phase inversion process film (including film-forming process and membrane performance influencing factors) as well as the nature of the polyphenylene ether and the aspects of the application in the membrane preparation, respectively, were introduced. Finally, the research significance and main contents of this paper. Chapter II triethanolamine as aminating agent, brominated polyphenylene ether, benzyl with triethanolamine react directly in the casting solution, to give a cast film material containing strong basic group and placed in the water after coating gel, to obtain a positively charged asymmetric membrane. Different proportions of brominated polyphenylene ether with triethanolamine, of amination reagents and gel bath temperature impact on membrane performance and morphology. The third chapter examines the different evaporation time and relative humidity on the positively charged membrane performance including pure water flux, retention, pore size distribution and morphology. The results show that the evaporation time, and the relative humidity of the influence of the film with a general rule the contrary, this is because the evaporation process there are two mutually restricting factors: the evaporation of the solvent NMP and the membrane casting solution of the water-absorbing, NMP and cast film was evaporated The process of one-dimensional infrared results prove the the film liquid absorbent behavior. The pore size distribution and electron microscopy confirmed the membrane flux and rejection of the law. Furthermore, in order to make a comparison with the dry-wet phase inversion method, the evaporation time was extended to 12 hours (similar to the vapor deposition phase conversion primer method) to obtain a symmetrical structure film. Can be seen from the electron micrograph, like small ball of the spherical core and pinhole-shaped apertures on the surface of the film. Chapter IV is a detailed analysis of two-dimensional infrared method the absorbent process of casting solution. By N-methyl pyrrolidone, the NMP / BPPO solution, the two-dimensional infrared contrast analyzed OH stretching vibration region in the 3800-3100 cm -1 split into four peaks (3635,3533, 3392, and 3297 cm -1 ) were clearly attributable to infer the sequence of the formation of hydrogen bonds in the the membrane fluid absorption process, while according to change the order of the 2D asynchronous spectrum readout peak. The fifth chapter is a summary of the full text. In this paper, the triethanol amine as the amination agent in situ amination Preparation of a positively charged membrane, and explored different triethanolamine and the ratio of brominated polyphenylene ether, a different amine types, different evaporation time and the relative humidity on the membrane performance Finally, by means of two-dimensional infrared analysis and morphology of the membrane liquid absorbent.
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