【作者】 李宙雷；

【导师】 王华平；

【作者基本信息】 东华大学 ， 材料物理与化学， 2005， 硕士

【摘要】 聚丙烯腈（PAN）用于生产所使用的传统溶剂都存在着或多或少的缺点,如:腐蚀性强、易挥发、污染环境等等。随着绿色化学概念的提出,人们越来越多的开始关注对环境的保护,离子液体作为绿色溶剂之一是当今绿色化学研究的热点。离子液体（Ionic liquids）是指完全由离子组成的液体,是低温下呈液态的盐,也称为低温熔融盐,它一般由有机阳离子和无机阴离子所组成。 本文采用两步法合成了咪唑类离子液体,通过红外光谱、核磁共振及元素分析等方法分析了所合成的离子液体1-丁基-3-甲基咪唑氯化盐（[BMIM]Cl）和1-丁基-3-甲基四氟硼酸盐（[BMIM]BF₄）的结构,结果表明,所合成的离子液体的结构与理论结构具有很好的一致性。 在此基础上,研究了水以及丙酮对离子液体折光指数的影响,并根据溶液折光指数与水及丙酮摩尔分数的关系,讨论了两者与离子液体之间在不同区域相互作用的机理,发现在富盐区（摩尔分数小于50%）,由于离子液体与水及丙酮之间形成氢键,使得溶液折光指数变化不大;在富水（丙酮）区（摩尔分数大于50%）,由于多余的水及丙酮的存在,使溶液的折光指数显著减小。 着重研究了聚丙烯腈在[BMIM]BF₄和DMF中特性粘度的变化。结果更多还原

【Abstract】 Nowadays the traditional solvents of PAN for the industry have more or less disadvantages, such as high corrosion, volatilization and environment pollution. With the appearance of the conception of green chemistry, more and more attention has been paid to environment protection. Ionic liquids have been researched warmly as one kind of green solvents. Ionic liquids are organic salts that are liquids at room temperature, which contain organic cations and inorganic anions.In this paper, two-step method is used to synthesize ionic liquids. Infrared spectrum analysis （FTIR）, nuclear magnetic resonance spectroscopy （NMR） and qualitative elementary analysis are employed to analyze the structure of l-butyl-3-methylimidazolium chloride （[BMIM]C1） and l-butyl-3-methylimidazolium tetrafluoroborate （[BMIM]BF4） which are synthesized in our lab. The results are identical with theoretical structures.And then, the influence of water and acetone on the refraction indexof ionic liquid was studied. Discussion on the interaction fundamental of water/acetone and [BMIM]BF4 is performed, according to the relation of molar fraction of water/acetone and solution refraction index. It is shown that in the salt-rich region （molar fraction less than half）, the solution refraction index changes smoothly for the hydrogen bonds between water/acetone and [BMIM]BF4; in the water/acetone-rich region （molar fraction more than half）, the solution refraction index decreases remarkably for the free water/acetone.The variety of intrinsic viscosities of PAN in [BMIM]BF4 and DMF were studied. The result revealed that the curve of reduced viscosities （η_sp/C） vs. concentration was not linear but upward as the concentration below definite concentration. At the same time the results revealed that the intrinsic viscosity of PAN/DMF was higher than that of PAN/[BMIM]BF₄. The intrinsic viscosity of PAN/[BMIM]BF₄ was more sensitive to temperature. But the intrinsic viscosities of both solutions decreased with the increase of temperature.Meanwhile the molecular weights of the PAN samples were obtained by GPC and the Mark-Houwink constants of PAN in [BMIM]BF₄ were determined. The Mark-Houwink equation is: [η]= 5.87 X 10^-4 M_η⁰.6268 . The molecular weights of PAN were measured at different conditions. The results showed that only using DMF with NaNO₃ as eluant and using a PAN sample with known molecular weight and wide molecular weightdistribution as a standard sample, the final molecular weight was reliable. Finally the Z-average size and distribution of PAN in [BMIM]BF₄ and DMF were studied by the laser size detector and AFM. The results of the laser size detector showed that the size of PAN in [BMIM]BF₄ decreased with the decrease of concentration, while the size distribution increased accordingly. The size of PAN in DMF changed slightly which decreased first and then increased with the concentration. At the same time, the results obtained by the method of AFM were identical with the results which were obtained by the method of laser size detector.更多还原