纳米聚苯胺及其复合粒子的制备研究

【作者】 周国庆；

【导师】 叶明泉；

【作者基本信息】 南京理工大学 ， 材料学， 2007， 硕士

【摘要】 导电聚苯胺作为一种新型的功能高分子材料，越来越受到科学家们的关注。这不仅是因为它具有合成方法简单、掺杂机制独特、环境稳定性良好等优点，而且它还具有广阔的开发与应用前景。纳米材料的尺寸效应、量子效应、表面效应等赋予其特殊的物理性能和化学性能。因此将纳米技术引入聚苯胺的制备工艺中，可以使其集导电性和纳米颗粒功能于一体。针对导电气溶胶要求质量轻和导电性良好的特性，选用密度小、价格便宜空心微珠为核，以导电性良好、性能稳定聚苯胺为壳，制得了聚苯胺包覆空心微珠复合粒子。本课题主要研究了三个方面的内容：1．微乳液聚合法制备纳米聚苯胺：研究乳化剂种类、聚合时间和引发剂滴加时间对聚苯胺粒子粒径和分散性的影响；研究乳化剂SDBS／An摩尔比、引发剂（NH₄）₂S₂O₈／An摩尔比和聚合体系的温度对聚苯胺粒子电导率和粒径的影响，得到了微乳液制备纳米聚苯胺的最佳工艺条件：SDBS／An摩尔比为1.5，（NH₄）₂S₂O₈／An摩尔比为1.25，聚合体系温度为10℃，体系的pH值为0.3，控制引发剂（NH₄）₂S₂O₈滴加时间为30min，反应聚合4h时，利用该工艺制备的聚苯胺纳米粒子的分散性最好，粒径大约在40nm左右，电导率数量级为10⁰S／cm。2．分散聚合法制备纳米聚苯胺：研究了分散剂的种类、分散剂PVP用量、引发剂浓度和分散介质对聚苯胺粒子的粒径和分散性的影响；以及盐酸浓度对聚苯胺电导率和产率的影响，得到了分散聚合制备纳米聚苯胺的最佳工艺条件：PVP浓度为8g／L，APS／An摩尔比为2，盐酸浓度为1.0mol／L，醇水比为5：5，制备的聚苯胺纳米粒子粒径约为60nm左右，且分散性较好，电导率数量级为10^-1S／cm。3．微乳液聚合法制备聚苯胺包覆空心微珠复合粒子：研究乳化剂种类、SDBS的用量和空心微珠的用量对复合粒子包覆效果的影响，得到了制备包覆均匀、致密复合粒子的最佳工艺条件：苯胺1g、SDBS乳化剂3.48g、空心微珠0.4g、引发剂过硫酸铵2.85g、20℃氮气保护下反应4h。更多还原

【Abstract】 Conductive polyaniline as a new material of functional polymer is given moreandmore attention by scientists because of its simple synthesis methods, particulardopingmechanism, excellent environmental stability, as well as wide application.Nanomaterial has the special physical and chemical properties. Introducingnanotechnology into the synthetical technology of polyaniline, it has conductivity andnanoparticle function togethere. Because conductive aerosol particles require light qualityand good conductivity, we choose small desity fly-ash hollow cenosphere as core and goodconductive polyaniline as shell, polyaniline/fly-ash hollow cenosphere composite particlewith core-shell structure were prepared. The main content of research include three aspectsas follow:Preparation of polyaniline nanoparticles with microemulsion polymerization method:the influences of the type of emulsifier, polymerization time and the time ofpolymerization initiator dropping on the particle size and particle size distribution ofpolyaniline nanoparticles were discussed. The effects of the molar ratio of sodiumdodecylbenzene sulfonate to aniline, the molar ratio of ammonium persulphate to anilineand the system of the reaction temperature on conductivity and the particle size ofnanoparticles were also studied. The optimum technology conditions for the preparation ofpolyaniline nanoparticles in microemulsion were obtained: the molar ratio of emulsifiersodium dodecylbenzene sulfonate Acid to aniline was 1.5:1. The molar ratio of initiatorammonium persulphate to aniline was 1.25:1. The reaction temperature and the pH value ofthe system was respectively 10℃and 0.3. The time of polymerization initiator droppingwas controlled at 30 min. The polymerization time continued for 4 hours. Particle sizedistribution of polyaniline nanoparticles of this preparation techniques was best andnarrowest. Particle size was about 40nm. The electrical conductivity is around 10⁰ S/cm.Preparation of polyanline nanoparticles with dispersion polymerization method: theinfluences of the type of dispersant, the concentration of polyvinylpyrrolidone, theconcentration of ammonium persulphate, dispersion media on the particle size and particlesize distribution of polyanline nanoparticles were discussed. The effects of theconcentration of the Hydrochloric Acid on conductivity and the yield of polyanlinenanoparticles were also studied. The optimum technology conditions for the preparation ofpolyaniline nanoparticles with dispersion polymerization were attained: The concentrationof polyvinylpyrrolidone was 8g/L. The molar ratio of ammonium persulphate to anilinewas 2:1. The concentration of the Hydrochloric Acid was 1mol/L. The volume ratio of ethanol and water of the dispersion media was 5:5. Particle size of polyanline nanoparticlesof the preparation techniques was about 60nm and particles had good dispersity. Theelectrical conductivity is around 10^-1S/cm.Preparation of nano-polyaniline/hollow cenosphere composite particle with core-shellstructure by microemulsion polymerization: the influences of the kind of emulsifier,sodium dodecylbenzene sulfonate content, hollow cenosphere content on compositeparticle coated effect were studied. The optimum technology conditions for the preparationof the even and compact coated polyaniline / hollow cenosphere composite particle inmicroemulsion were attained: aniline 1g, sodium dodecylbenzene sulfonate 3.48g, hollowcenosphere 0.4g, ammonium persulphate 2.85g, under the protection of nitrogen,temperature 20℃, reaction 4h.更多还原