| In this thesis, the preparation, performance determination and application of microporous starch, crosslinked microporous starch and crosslinked microporous starch microspheres was carried out. The microporous starch was obtained by enzymatic hydrolysis with native corn starch, and the crosslinked microporous starch was prepared by crosslinking with the microporous starch, and the crosslinked microporous starch microspheres was synthesized in final by two-steps crosslinking with the microporous starch via the method of inverse emulsion polymerization. After that, the adsorption properties of products were mearsured. The factors which can affect the adsorption rate of products were investigated in systematically. According to the results, the reaction conditions were optimized. Besides, the hydrolysis rate was studied in the microporous starch synthesizing process. After the products of crosslinked microporous starch prepared, the crosslinking degree and freeze-thaw stability of them were investigated. Finally, the adsorption properties of crosslinked microporous starch microspheres were studied with nicotine. The main results were summarized as follows:1. The microporous starch was obtained by enzymatic hydrolysis reaction. During the process, the main reaction conditions which are expected to affect adsorption rate of the products were investigated systematically, including mα-amylase/mglucoamylase, menzyme/mstarch, Vsolution/mstarch, pH, temperature and time of enzymatic reaction. According to the results, the optimal reaction conditions were obtained. Moreover, the hydrolysis rates in each reaction conditions were studied to realize the relationship between the hydrolysis rates and adsorption rates. FTIR was used to compare the structural differences between the native corn starch and microporous starch. SEM images displayed the morphology changes after the treatment with enzyme. The results of XRD showed the changes in crystallinity. DSC determined that the variation of gelatinization temperature.2. The crosslinked microporous starch was prepared by crosslinking with the microporous starch, which obtained by last step. The effect of each reaction condition on adsorption rate of the products is studied systematically, which included NaOH/mstarch, reaction temperature and time of alkalization, VECH/mstarch, h, pH, reaction temperature and time of crosslinking. The optimal reaction conditions were obtained. FTIR spectra showed the characteristic peaks of the crosslinked microporous starch. And SEM photos revealed its surface morphology.3. The performance of crosslinked microporous starch prepared by last step was investigated. The relationships among each reaction condition, crosslinking degree of the products, and freeze-thaw stability were studied, In order to study that the changes in crystallinity, the native corn starch and crosslinked microporous starch were examined by XRD. DSC traces showed the alteration in gelatinization temperature.4. The crosslinked microporous starch microspheres was synthesized by two-steps crosslinking with the microporous starch via the method of inverse emulsion polymerization. The influence of reaction conditions to adsorption rate of the products, such as the different emulsifier (span 60, span 80, tween 60, tween 80), Vcyclohexane/Vsolution, mspan 60/mtween 80?,memulsifie/Vcyclohexane, mstarch/Vsolution, mNNMBA/mstarch, mCAN/mstarch, temperature and time of the crosslinking reaction with NNMBA, h, temperature and time of the crosslinking reaction with ECH, were investigated. The optimal reaction conditions about this method were obtained. Besides, the samples were characterized by FTIR, SEM, XRD and DSC.5. The experiments for absorbing nicotine of crosslinked microporous starch microspheres were conducted. According to the results, the adsorption kinetics and thermodynamics in this process were investigated. polymerization; adsorption rate; hydrolysis rate; settlement volume; adsorption nicotine; adsorption kinetics; adsorption thermodynamics...
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