本文選題：磁性介孔二氧化硅 + 殼聚糖　； 參考：《安徽大學(xué)》2015年碩士論文

【摘要】：磁性介孔二氧化硅是一種新型的納米復(fù)合材料,具有較大的比表面積、規(guī)整的納米尺寸的孔結(jié)構(gòu)、生物相容性、生物可降解性,被廣泛應(yīng)用于靶向載藥、催化、固定化酶以及污水處理等方面。殼聚糖是自然界中第二大多糖甲殼素,脫乙酰之后的產(chǎn)物,具有廉價(jià)、生物相容性、生物可降解性、無毒和吸附性質(zhì)等優(yōu)點(diǎn),被廣泛應(yīng)用于污水處理、生物醫(yī)藥等領(lǐng)域。為了得到兼具二者優(yōu)點(diǎn)的復(fù)合材料,本文制備出了殼聚糖包覆的磁性介孔二氧化硅(Fe3O4/mSiO2/CS)復(fù)合材料；為了增強(qiáng)殼聚糖包覆的磁性介孔二氧化硅納米粒子的性能,在此體系中引入了聚甲基丙烯酸,主要的研究內(nèi)容和結(jié)論如下：(1)分別采用水熱法和化學(xué)共沉淀法制備了四氧化三鐵(Fe3O4)納米粒子,并以兩種方法得到的Fe304納米粒子為核,通過溶膠-凝膠法包覆二氧化硅,并通過離子交換的方法,用硝酸銨-乙醇混合溶液移除表面活性劑,得到介孔結(jié)構(gòu)的Fe3O4/mSiO2納米粒子。由于以水熱法制備的Fe304納米粒子為核得到的Fe3O4/mSiO2納米粒子團(tuán)聚現(xiàn)象比較嚴(yán)重,所以采用化學(xué)共沉淀法制備的Fe304納米粒子為核獲得Fe3O4/mSiO2納米粒子。分別用FTIR、TEM、XRD等表征方法對Fe3O4/mSiO2納米粒子進(jìn)行表征。結(jié)果顯示：Fe3O4/mSiO2納米粒子的尺寸為100nm,單分散性良好；比表面積和孔體積分別為665.48m2/g和1.00cm3/g,孔徑分布呈單峰,具有均勻的介孔結(jié)構(gòu)且尺寸為2.9nm。(2)以Fe3O4/mSiO2納米粒子為核,采用“兩步法”和“一步法”兩種方式得到Fe304/mSi02/CS納米粒子。兩步法：首先對Fe3O4/mSiO2納米粒子進(jìn)行羧基化改性,然后再利用羧基和殼聚糖上的氨基的作用把殼聚糖包覆在Fe3O4/mSiO2納米粒子上,所得到的Fe3O4/mSiO2/CS納米粒子中,殼聚糖的厚度為10nm；測試了Fe3O4/mSiO2/CS納米粒子對藥物釋放的pH響應(yīng)性,結(jié)果證明其具有pH響應(yīng)性。由于“兩步法”的操作繁瑣且實(shí)驗(yàn)過程中用到的甲苯、N,N-二甲基甲酰胺(DMF)和二甲基亞砜(DMSO)等有機(jī)溶劑比較難除去,因此,又采用“一步法”制備Fe3O4/mSiO2/CS納米粒子。一步法：通過Y-縮水甘油醚氧丙基三甲氧基硅烷(KH560)把殼聚糖直接包覆在Fe3O4/mSiO2納米粒子上,得到Fe3O4/mSiO2/CS納米粒子,并用于吸附水中的亞甲基藍(lán),通過表征可得Fe3O4/mSiO2/CS納米粒子的形貌為球形,殼聚糖殼層的厚度為5nm。Fe3O4/mSiO2/CS納米粒子對亞甲基藍(lán)具有良好的吸附效果,吸附量為43mg/g,吸附動(dòng)力學(xué)符合二階動(dòng)力學(xué)方程,吸附等溫線符合Freundlich等溫模型,吸附染料之后有很好的磁響應(yīng)性能,并且能夠快速分離。(3)為了進(jìn)一步提高對亞甲基藍(lán)的吸附能力,以Fe3O4/mSiO2納米粒子為核,采用原位聚合法把殼聚糖和聚甲基丙烯酸共同包覆在Fe3O4/mSiO2納米粒子上,得到Fe3O4/mSiO2/CS-PMAA納米粒子。通過TEM、RT-IR、TGA和Zeta電位等表征方法對其表征,結(jié)果表明CS和PMAA所占的比重為23%,包覆聚合物之后Zeta電位向更負(fù)的位置移動(dòng),磁飽和強(qiáng)度由21.9eum/g降到6.1um/g,但仍然具有超順磁性。研究了吸附時(shí)間和初始濃度對Fe3O4/mSiO4/CS-PMAA納米粒子吸附亞甲基藍(lán)的影響,結(jié)果顯示：Fe3O4/mSiO2/CS-PMAA納米粒子對亞甲基藍(lán)的吸附量達(dá)到101mg/g,吸附動(dòng)力學(xué)符合二階動(dòng)力學(xué)方程,吸附等溫線符合Freundlich等溫模型。
[Abstract]:Magnetic mesoporous silica is a new kind of nanocomposite. It has large specific surface area, regular nano size pore structure, biocompatibility and biodegradability. It is widely used in targeted drug loading, catalysis, immobilized enzyme and sewage treatment. Chitosan is second most sugar chitin in nature and deacetylation. The later products, with the advantages of cheap, biocompatibility, biodegradability, non-toxic and adsorption properties, are widely used in the fields of sewage treatment, biological medicine and other fields. In order to obtain the composite materials with two advantages, the chitosan coated magnetic mesoporous silica (Fe3O4/mSiO2/CS) composite was prepared in order to enhance the shell. The properties of magnetic mesoporous silica nanoparticles coated with chitosan have been introduced in this system. The main contents and conclusions are as follows: (1) Fe3O4 nanoparticles were prepared by hydrothermal method and chemical coprecipitation method respectively, and the Fe304 nanoparticles obtained by two methods were nucleated by sol-gel. The Fe3O4/mSiO2 nanoparticles of mesoporous structure were obtained by the method of ion exchange and the method of ion exchange. The mesoporous structure was obtained by removing the surface active agent in the mixture of ammonium nitrate and ethanol. The aggregation of Fe3O4/mSiO2 nanoparticles obtained by the Fe304 nanoparticles prepared by hydrothermal method was more serious, so the chemical coprecipitation method was used to prepare the nanoparticles. The Fe304 nanoparticles are nucleed to obtain Fe3O4/mSiO2 nanoparticles. The Fe3O4/mSiO2 nanoparticles are characterized by FTIR, TEM and XRD respectively. The results show that the size of Fe3O4/mSiO2 nanoparticles is 100nm, and the monodisperse property is good; the specific surface area and pore volume are 665.48m2 /g and 1.00cm3/g, the pore size distribution is single peak and uniform. The mesoporous structure and the size of 2.9nm. (2) were nucleated with Fe3O4/mSiO2 nanoparticles. The "two step" and "one step" method were used to obtain the Fe304/mSi02/CS nanoparticles. The two step method: the carboxylation of the Fe3O4/mSiO2 nanoparticles was first modified, and then the chitosan was coated on the Fe3O4 with the action of the carboxyl group and the amino group on the chitosan. On the /mSiO2 nanoparticles, the thickness of the chitosan was 10nm in the obtained Fe3O4/mSiO2/CS nanoparticles, and the pH responsiveness of the Fe3O4/mSiO2/CS nanoparticles to the drug release was tested. The results showed that the chitosan was pH responsive. The "two step" operation was complicated and the toluene, N, N- two methylformamide (DMF) and two methyl methamides used in the experimental process. DMSO and other organic solvents are difficult to remove. Therefore, Fe3O4/mSiO2/CS nanoparticles are prepared by one step method. One step method: using Y- glycidyl methoxypropyl trimethoxy silane (KH560) to encapsulate chitosan directly on Fe3O4/mSiO2 nanoparticles and get Fe3O4 /mSiO2/CS nanoparticles and used to adsorb methylene blue in water. The morphology of Fe3O4/mSiO2/CS nanoparticles is spherical. The thickness of the chitosan shell is 5nm.Fe3O4/mSiO2/CS nanoparticles with a good adsorption effect on methylene blue. The adsorption capacity is 43mg/g. The adsorption kinetics accords with the two order kinetic equation. The adsorption isotherm is consistent with the Freundlich isothermal model. After the adsorption, the dye is good. (3) in order to further improve the adsorption capacity of methylene blue, Fe3O4/mSiO2 nanoparticles are used as core. In situ polymerization, chitosan and polymethacrylic acid are coated on Fe3O4/mSiO2 nanoparticles, and Fe3O4/ mSiO2/CS-PMAA nanoparticles are obtained by TEM, RT-IR, TGA and Zeta potential. The results show that the proportion of CS and PMAA is 23%. After coated polymers, the Zeta potential moves to a more negative position, the magnetic saturation intensity is reduced from 21.9eum/g to 6.1um/g, but it still has superparamagnetic. The effect of adsorption time and initial concentration on the adsorption of methylene blue with Fe3O4/mSiO4/ CS-PMAA nanoparticles is studied. The results showed that the adsorption capacity of Fe3O4/mSiO2/CS-PMAA nanoparticles to methylene blue reached 101mg/g, and the adsorption kinetics accorded with the two order kinetic equation, and the adsorption isotherm accorded with the Freundlich isothermal model.

【學(xué)位授予單位】：安徽大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2015
【分類號】：TB383.1;TQ127.2

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本文編號：1808487