节点文献

聚苯胺及其衍生物薄膜的制备和湿敏性研究

Preparation of Polyaniline and Relative Derivatives and Their Humidity Sensing Properites

【作者】 周铁莉

【导师】 赵纯;

【作者基本信息】 吉林大学 , 微电子学与固体电子学, 2009, 博士

【摘要】 本论文主要以苯胺、苯胺衍生物和氧化物为基材,制备聚合物、共聚物及复合物功能材料,使用扫描电镜、红外光谱、紫外光谱及热重等分析手段对产品进行了表征,并进一步对其湿度敏感性质进行了研究。分别以盐酸、磷酸、酒石酸和硫酸作为掺杂剂,在幻灯片基底上合成具有一维结构的聚邻苯二胺微/纳米材料。不同酸掺杂条件,磷酸掺杂的聚邻苯二胺具有响应快、恢复性好和稳定性高的湿敏性能研究。磷酸掺杂的邻苯二胺/苯胺共聚物,反应物添加比率的不同对热稳定性、形貌及湿敏性有一定的影响。樟脑磺酸掺杂的邻苯二胺/苯胺共聚物的有较好的湿敏稳定性和重复特性。反应物添加比率的不同、反应时间的不同及掺杂盐酸浓度的不同,对间苯二胺/苯胺共聚物生成的纳米粒子形状具有一定的影响。当邻甲苯胺/苯胺比率为1:1时,邻甲苯胺/苯胺共聚物有较好的湿敏性质。这是因为水分子的进入增加了共聚物和极化的水分子之间的相互作用引起电子的电荷沿着聚合物骨架离域。在聚邻甲苯胺/TiO2复合物的制备过程中,TiO2的加入增加了聚邻甲基苯胺的比表面积并增大了复合物内部孔隙度,提高了薄膜的湿敏性能,,更加有利于在湿敏传感器中的应用。在共聚物的合成与制备中,我们使用原位氧化聚合法在电极表面制备出均匀的聚合物膜,克服了传统的旋涂制膜法中的不足,为制备微型电子器件开辟了道路。为了研究聚苯胺的导电机理,在现场外加电压下,利用红外和拉曼光谱对聚苯胺进行研究,结果显示,应用外电压使光谱的强度和峰位有所改变。电压在0-75 V能产生大的平均跳跃能,可以使电荷在导电区域间的跳跃;在75-175 V,是焦耳热的影响而使聚苯胺的电导率降低。

【Abstract】 With the development of the modern industry and the increasing of people’s living, the measurement and control accuracy of humidity put forward the higher demands. Therefore, it is increasing becoming importance to exploiture the high-performance, long-life humidity sensors. Compared with inorganic materials, macromolecule humidity materials own to easy preparation and processing. Furthermore, different physical and chemical properties material can be gaind through the molecular structure modified. It is received more attention due to abundance source of materials, wide range of relative humidity, small hysteretic of humidity and fast response.As the most investigated conducting polymers, polyaniline (PANI) and its derivtives have attacted considerable attention due to their special doping mechanism, high environmental stability, ease of processability and low cost, and the application in many fields.PANI has been obtained by chemical and electrochemical methods. However, it has many poor properites, for example, low molecular weight, poor solubility in common organic solvents and poor processing which limits their application. Two groups of the polymer have prepared and shown the special properties to enhance the electrical, chemical and physical properties such as copolymer, composite, dual-layerand mixture.Based on the above background, in order to improve the processability and stability of PANI, we chose aniline, aniline derivatives and oxides as the precursor to prepare the functional materials of polymer, copolymer and composite by using a simple method. Study the humidity sensing characteristics of these materials. We prepared the polymer films, copolymer films and polymer/inorganic composites by insitu polymerization on the slide on the gold-plated sensor electrodes.1. We prepared poly(o-phenylenediamine) based on self-assembled belt, board, block and strip nanostuctures by using a chemical oxidative polymerization of o-phenylenediamine (oPD) doped with hydrochloric acid, phosphatic acid, tartrate acid and sulfuric acid dopant on the lantern slide substrate. Study the humidity sensing characteristics of the materials doped with different acid. We found PoPD doped with phosphatic acid have the fast humidity and response reproducibility.2. We synthesis the oPD/An copolymer with the same method doped with phosphatic acid. Study the effect of the thermal stability, morphology and humidity sensing characteristics with the changing of the oPD/An molar ratios. We found that the copolymer has good thermal stability, conductivity and repose-recovery with the oPD/An molar ratios of 80:20. At the same time, we found that the copolymer has the fast sensitivity and reponse-recovery doped with D-camphor-10-sulfonic acid (CSA) dopant.3. We prepared m-phenylenediamine(mPD)/An copolymer by in-situ polymerization. By changing the molar ratios of reactants, reaction time, and concentration of hydrochloric acid, the morphology of nanoparitcles can be changed. We make a further humidity study on the copolymer.4. We synthesis the o-toluidine/An copolymer doped with hydrochloric acid. We found that the copolymer has good repose-recovery with the o-toluidine /An molar ratios of 1:1. This attribute to the interaction of copolymer and water molecules which may cause the electron charge delocalization along the polymer backbone.5. We prepare poly(o-toludine)/TiO2 composite doped with hydrochloric acid. We found that the increasing surface area as increased with the content of TiO2. This composite maybe used in the applications of sensors. The method of in-situ oxidative polymerization overcomes the shortcoming of the membrane by using traditional spin-coaitng.6. We study the mechanism of the PANI by using the FT-IR and Raman spectra with external voltage. Application of external voltage reduced the intensity in FTIR spectra and resulted in the shift of band situation.We concluded that external voltage could produce large average hopping energy, which allowed the charge transfer by hopping between the conducting domains during 0–75 V. The deprotonation of PANI was caused by Joule heating effect, resulting in the decreasing conductivity from 75 to 175V.

【关键词】 苯胺苯胺衍生物共聚物湿敏性
【Key words】 polyanilinepolyaniline derivativecopolymerhumidity
  • 【网络出版投稿人】 吉林大学
  • 【网络出版年期】2009年 08期
节点文献中: 

本文链接的文献网络图示:

本文的引文网络