【作者】 肖书虎；

【导师】 甘复兴；

【作者基本信息】 武汉大学 ， 环境科学， 2005， 硕士

【摘要】 金属材料和它所处的环境介质之间发生化学或电化学作用,引起材料失效,称为金属腐蚀。金属腐蚀现象十分普遍,它给社会带来了巨大的经济损失,造成了许多灾难性的事故,耗竭了宝贵的资源与能源,严重地污染了环境,阻碍了高新技术的正常发展。寻求一种价廉、高效而又安全的腐蚀防护手段一直是腐蚀科学工作者的追求。自Deberry首次发现聚苯胺（polyaniline,简称PANI）的防腐性能后,聚苯胺作为一种优良的防腐材料逐渐引起重视,并且成为导电聚苯胺十分有前景的应用领域。目前,几乎所有的文献均是将聚苯胺直接电聚合、溶解涂覆或做成涂料涂覆在金属表面上进行腐蚀防护的。但这几种方法都具有严重的弱点,故应用受到了限制。 本文采用新的工艺制备了独立的聚苯胺压片电极,首次提出并实现了聚苯胺对铁基金属的伽伐尼阳极保护技术,讨论了其机理和可行性,得到如下结果:（1） 采用化学氧化法合成聚苯胺,分别考察了聚合介质中酸的种类、浓度、氧化剂与苯胺单体的摩尔比及反应时间、反应温度对聚合产物的影响,确定最佳的聚合条件为:0.5M苯胺单体+2M HClO₄,过硫酸铵与苯胺的摩尔比为1:1,反应温度为0℃左右,反应时间为6h。 （2） 采用简易的新工艺制备了独立的聚苯胺压片电极,具有一定的机械强度。通过动电位极化和恒电位极化实验证实了该电极具有良好的电化学性能,能提供较大的初始电流和稳态电流。 （3） 采用聚苯胺压片电极与1Cr13不锈钢相耦合的方法,分别改变PANI/1Cr13面积比、酸浓度、温度、酸种类等几个影响因素,研究了PANI对1Cr13不锈钢伽伐尼阳极保护效应。结果表明,PANI压片电极在诸多实验条件下都能对1Cr13不锈钢提供高效的伽伐尼阳极保护,其保护效率几乎达到100%。 （4） 除1Cr13不锈钢以外,PANI压片电极对其他铁基金属也能提供高效的伽伐尼阳极保护效应,如碳钢、304、316和321不锈钢等。聚苯胺伽伐尼阳极保护对可钝铁基金属均适用。 （5） 对聚苯胺伽伐尼阳极保护技术的可行性和安全性进行了讨论,分析表明该技更多还原

【Abstract】 Corrosion is the destructive result of chemical or electrochemical reaction between a metal or metal alloy and its environment, which is a common phenomenon. It occurs in all over the fields in national economy. Where metal or metal alloy is used, corrosion exists absolutely to some extent. It is aware that corrosion has consumed enormous economic cost, brought many disastrous accidents, exhausted the precious resource, contaminated the environment and even prevented the development of high-tech. It is always our aim to find a cheap, effective and secure measure to prevent corrosion. Since Deberry first found the anticorrosion character of polyaniline （short for PANI）, PANI has become an important material to prevent corrosion by the means of coating on the surface of metals as followed: depositing directly, dissolving and coating, coating as paint. But the application of all these methods is restricted because of their fatal shortcomings.In this work, we first suggest and study a new anodic protection method called Galvanic Anodic Protection to protect ferrous metals. The results are as follows:（1） PANI was chemically synthesized. The influencing factors, including the kind and concentration of the acid in the synthesized solution, the mol ratio of oxidant to aniline monomer, reaction temperature and reaction time to the synthesized PANI, were examined. The synthesized conditions were optimized as follows: the solution is 0.5M aniline and 2M HClO4, the mol ratio of （NH₄）2S2O8 to aniline is 1:1, the reaction temperature is about 0℃, and the reaction time is 6h.（2） The separate PANI powder electrode has been made by a new and easy method, and its mechanical intensity is very good. It was proved that the PANI powder electrode had good electrochemical properties and could provide initial current and steady current by potentiodynamic polarization and potentiostat polarization.（3） Coupling the PANI powder electrode with lCrl3, the Galvanic Anodic Protection of PANI to stainless steel was studied and the major influencing factors such as theratio of PANI to lCrl3, the concentration of the acid, the temperature and the kind of acid were investigated. The results show that the PANI powder electrode can protect lCrl3 from corrosion in many experimental conditions and the protection efficiency reaches almost 100%.（4） Many results indicate that PANI powder electrode can provide Galvanic Anodic Protection to other metals besides lCrl3, such as carbon steel, 304, 316, 321 and so on. Generally, the Galvanic Anodic Protection effect of PANI is available to any passive ferrous metals.（5） Finally, the feasibility and security of the Galvanic Anodic Protection of PANI as a new applicable technology were discussed. The technology is highly efficient, cheap, easily operating and safe and may be extensively applied to protecting ferrous metals in acid solutions.The main innovations and specialties of this work are as follows:（1） The PANI powder electrode was first successfully made, which had good electrochemical properties, stability and mechanical intensity, and can be used repeatedly.（2） The passivation behavior and mechanism of PANI to metals were measured and studied by coupling PANI with ferrous metals. The experimental method was intuitionistic and reliable.（3） The concept about Galvanic Anodic Protection of PANI was first proposed. The Galvanic Anodic Protection of PANI to ferrous metals and the feasibility of this technology were studied experimentally.更多还原