【作者】 孙桂香；

【导师】 倪沛红；

【作者基本信息】 苏州大学 ， 应用化学， 2009， 硕士

【摘要】 本论文研究内容包含三个部分:第一部分,合成一系列阳离子型两亲性无规聚合物,测定共聚体系的竞聚率,研究共聚物水溶液的性质和在水相及乙醇-水混合溶剂中的自组装行为;第二部分,合成一系列具有pH和温度响应性的含氟两亲性无规共聚物,研究共聚物水溶液的性质和不同pH条件下在水溶液中的自组装行为;第三部分,研究pH响应性阳离子型微凝胶的制备及性质研究。第一部分:阳离子型两亲性无规共聚物的合成、表征、竞聚率测定及自组装研究以偶氮类引发剂AIBN（偶氮二异丁腈）为引发剂,正十二硫醇为链转移剂,无水乙醇为溶剂,采用普通自由基溶液共聚的方法对亲水性单体甲基丙烯酰氧乙基三甲基氯化铵（MADQUAT）和疏水性单体甲基丙烯酸十八烷酯（SMA）进行溶液共聚,并利用FT-IR,¹H NMR和MALDI-TOF MS对产物的结构和组成进行表征,结果表明此两亲性阳离子型共聚物已成功合成。采用核磁共振测定共聚物的组成,用F-R方法计算出r_MADQUAT=0.83,r_SMA=0.25。利用表面张力法和接触角法测定共聚物在水溶液中的表面活性,结果表明,该阳离子型两亲性共聚物具有良好的表面活性。共聚物在水溶液中的临界聚集浓度（cac）通过表面张力法、荧光探针法、电导率法的测定而获得。将此两亲性阳离子型无规共聚物置于于水或乙醇/水的混合溶剂中进行自组装,利用透射电镜（TEM）和动态激光光散射对共聚物的自组装行为进行研究,实验结果显示该无规共聚物在水相或乙醇/水混合溶液中都能形成良好的自组装。第二部分:具有pH和温度响应性的两亲性含氟无规共聚物的合成和自组装研究通过常规自由基溶液共聚的方法,合成了一系列具有pH/温度响应性的两亲性含氟无规共聚物（PDMAEMA-co-PDFMA）。亲水性单体为甲基丙烯酸-2-（二甲氨基）乙酯（DMAEMA）,疏水性单体为甲基丙烯酸十二氟酯（DFMA）。通过核磁共振(¹H NMR、¹⁹F NMR)、红外光谱（FT-IR）、凝胶渗透色谱（GPC）等对含氟共聚物的结构、分子量及分子量分布进行表征。共聚物的热性质通过热重分析（TGA）进行研究,结果表明此共聚物具有良好的热稳定性。对含氟共聚物的水溶液进行表面张力和接触角测试,结果表明,此两亲性含氟无规共聚物具有很高的表面活性,能显著降低水的表面张力。共聚物的pH/温度响应性通过表面张力测定、电导率测定、稳态荧光法、浊点测定进行研究,结果显示此含氟共聚物具有明显的pH/温度响应。共聚物在水溶液中的临界聚集浓度（cac）随着疏水性单体（DFMA）片段的增加而变小。通过透射电镜（TEM）、¹H NMR谱图对共聚物在不同pH水溶液中自组装行为进行表征。结果显示,共聚物PDMAEMA-co-PDFMA在水溶液中可以自组装成各种形态的聚集体。第三部分:pH响应性阳离子型微凝胶的制各及性质研究以甲基丙烯酸-（N,N-二甲氨基）乙酯（DMAEMA）和丙烯酸乙酯（EA）为共聚单体,二甲基丙烯酸乙二醇酯（EGDMA）为交联剂,采用半连续乳液聚合法,制备了具有pH响应性的阳离子型微凝胶,并研究不同聚合条件对所合成的微凝胶性质的影响。通过透射电子显微镜（TEM）、激光粒度分析仪和流变仪对微凝胶进行一系列表征。研究了介质pH值对微凝胶的形态、平均粒径、zeta电位、溶液浊度（透光率）的影响,以及不同浓度氯化钠溶液对微凝胶分散体系稳定性的影响。结果表明,该阳离子型微凝胶体系具有良好的pH响应性,在pH 7左右发生相转变。此外,研究表明不同浓度氯化钠溶液对微凝胶的稳定性有一定影响,临界絮凝浓度约为1.3 mol·L^-1。更多还原

【Abstract】 There are three parts included in this thesis research:（1） synthesis of a series of amphiphilic cationic random copolymers,measurement of reactivity ratios between the two monomers and research the self-assembly behavior in water and water-ethanol mixtures;（2） synthesis of a series of amphiphilic fluorinated random copolymers with pH/temperature response and research the self-assembly behavior in aqueous solution of various pH values;（3） synthesis of a series of pH-responsive cationic microgels and research the pH-responsive behavior.（1） Synthesis of Amphiphilic Cationic Copolymers and Their Self-Assembly Behavior in Water and Water-Ethanol MixturesIn this part,a series of amphiphilic cationic random copolymers,namely poly[2-（methacryloyloxy）ethyl trimethylammonium chloride-co-stearyl methacrylate] or poly（MADQUAT-co-SMA）,have been synthesized via conventional flee-radical copolymerization using 2,2’-azobisisobutyronitrile（AIBN） as initiator and n-dodecanethiol as chain transfer agent.The resultant products were then characterized by FT-IR,¹H NMR,MALDI-TOF MS measurements.The reactivity ratios(r_MADQUAT= 0.83,r_SMA=0.25) between the hydrophilic monomer MADQUAT and the hydrophobic monomer SMA were calculated by the Finemann and Ross method,which was based on the results of ¹H NMR analysis.The surface activity of the random copolymers was studied by the combination of surface tension and contact angle measurement.The critical aggregation concentrations（cac） of the copolymers in aqueous solution were determined by fluorescence probe method,electrical conductivity and surface tension measurement.Furthermore,using transmission electron microscopy（TEM）,we could observe the self-assembly morphology of these random copolymer.All the results show that amphiphilic cationic random copolymers have a good self-assembly behavior in water and water-ethanol mixtures,even if they are ill-defined copolymers.（2） Study on Novel Amphiphilic Fluorinated Random Copolymers with pH/Temperature Response and Their Self-Assembly Behavior A series of studies on amphiphilic fluorinated random copolymers with pH/temperature response were herein described,wherein the copolymers,poly[1H,1H, 7H-dodecafluoroheptyl methacrylate-co-2-（N,N-dimethylamino）ethyl methacrylate]or poly（DFMA-co-DMAEMA）,were synthesized via conventional free radical polymerization using 2,2’-azobisisobutyronitrile（AIBN） as initiator,and then characterized by FT-IR,¹H NMR,¹⁹F NMR,and gel permeation chromatography（GPC） technique.The thermal stability of the copolymers was examined by thermogravimetric analysis（TGA）.The aqueous solution behaviour of the copolymers was investigated by the combination of surface tension,electrical conductivity,fluorescence probe,cloud point and contact-angle measurement.The results indicate that the copolymers exhibit distinct pH/temperature-response properties and possess high surface activity.The critical aggregate concentration（cac） of the copolymers in aqueous solution decreases with the increase of hydrophobic DFMA segments.The self-assembly behaviour was studied by TEM analysis and ¹H NMR spectroscopy.A very interesting phenomenon was found that the aggregate morphologies changed as a function of the pH values of the aqueous solution.The mechanism of the self-assembly behavior was discussed.（3） Synthesis and Properties of pH-Responsive Cationic MicrogelsA series of pH-responsive cationic microgels have been synthesized via semi-continuous emulsion polymerization with 2-（N,N-dimethylamino）ethyl methacrylate（DMAEMA） and ethyl acrylate（EA） as comonomers,and ethylene glycol dimethacrylate as cross-linker.The effects of various conditions on the emulsion polymerization and the stability of microgels were studied in detail.The resultant microgels were characterized by transmission electron microscopy（TEM）,dynamic light scattering（DLS） and rheometry.The pH-responsive behavior of the microgels was investigated by the measurements of Z-average diameter,zeta potentials,and the solution transmittance of the microgels at different pH values.Furthermore,the influence of NaCl solution on the stability of the microgels in aqueous solution was also studied.All the results show that the cationic mircrogels possess well pH-responsive property,and the phase variation happens at pH 7.0.Furthermore,the addition of NaCl solution can influence the stability of the microgels and the critical flocculent concention is about 1.3 g L^-1.更多还原