苯胺类化合物的电子转移性质及抗爆机理研究

【作者】 靳明；

【导师】 郁章玉；

【作者基本信息】 曲阜师范大学 ， 物理化学， 2004， 硕士

【摘要】 自发展非铅抗爆剂以来，人们一直在积极寻找高效清洁的抗爆剂，明确抗爆机理对抗爆剂的研制开发显然有着重要的实践意义。前人对抗爆机理的研究多集中于金属抗爆剂，由于金属抗爆剂的使用业已受到限制，非金属抗爆剂的使用将会逐渐增多，非金属抗爆剂抗爆机理的研究在抗爆剂的发展中将起重要作用。但由于非金属抗爆剂电子转移机理复杂或在一般条件下不发生电子转移反应，从而使其抗爆机理的研究进展缓慢。本文用电化学技术研究具有抗爆性的非金属化合物的电子转移性质及过氧化物的影响，旨在探讨研究变价抗爆剂的抗爆机理的电化学方法。 许多苯胺类化合物，如苯胺、N-甲基苯胺、二苯胺是性能良好的非金属抗爆制，也是抗爆剂常用的调合组分，且具有电子转移性质，适于电化学研究。本文采用循环伏安法、现场紫外-可见光谱法、交流阻抗法，以抗爆剂中的常用辅助组分1，2-二氯乙烷作溶剂，研究了苯胺类化合物的电子转移性质。研究结果表明：苯胺类化合物的电化学氧化反应属自由基反应，在低浓度、非质子溶剂的条件下，苯胺类化合物正离子自由基的偶合方式主要为“尾-尾”式，其中N-甲基苯胺和N，N-二甲基苯胺的偶合方式呈现多样化。 抗爆剂的抗爆震作用是抑制或消除汽油在发动机内燃烧时产生的过氧化物。本文在分析苯胺类化合物电化学性质的基础上，通过研究苯胺类化合物与过氧化氢的作用，为芳香胺抗爆机理的研究提供了重要依据，并由此探讨抗爆剂的抗爆性与电化学性质的关系。研究结果表明：苯胺类化合物均能与过氧化氢发生作用，其中对甲苯胺和N，N-二甲基苯胺与过氧化氢的作用不明显，而N-甲基苯胺与过氧化氢反应较显著。而实际上采用胺类化合物作抗爆剂时，一般使用N-甲基苯胺、苯胺、邻甲苯胺及间甲苯胺，尚未见到使用对甲苯胺和N，N-二甲基苯胺的报道。这一实际应用情况与各苯胺类化合物所表现出的电化学性质是相符的，表明利用电化学性质探讨抗爆机理是可行的，也对抗爆剂的寻求具有指导意义。同时本文工作对苯胺类化合物的电聚合性能的研究与发展具有促进作用。更多还原

【Abstract】 More efficient and non-polluting antiknock have been seeking since developing nonleaded gasoline. It is obviously that clarifying the mechanisms of antiknock has important effects on developing new antiknock. So far, the mechanism of the metal antiknock has been paid more attention. However, the studies of the mechanisms of non-metal antiknock will play an important part in exploring new antiknock in the future, with non-metal antiknock being employed increasingly and metal antiknock restricted. But the study of the mechanisms of non-metal antiknock has developed slowly due to the complex of the electron-transfer mechanisms or no electron-transfer properties under common condition. The electron-transfer properties of non-metal antiknock and the effects of peroxide have been investigated with electrochemical technique, aiming at exploying electrochemical method of studying the mechanism of antiknock which has variable quantivalency.Many aromatic amine, such as aniline and N-methylaniline and diphenylamine, whose antidetonating quality are excellent, are not only often employed as concocting ingredient of antiknock but also suitable to research with electrochemical methods. We investigated the electron-transfer properties of aromatic amine in 1,2-dichloroethane which is a common auxiliary ingredient of antiknock by cyclic voltammetry and situ UV spectra and ac impedance spectroscopy. The research results indicate that the electrochemical oxidation reactions of aromatic amine belong to the free radical reaction. Under the conditions of low concentration and non-protonic solvent, the cation free radical produce substituted benzidines by tail-tail couplings. However, the couplings of N-methylaniline and N,N-dimethylaniline appear diversifying.The role of antiknock is to eliminate peroxide produced by the combustion of gasoline in engine. We have presented some important evidences to the antiknocking mechanisms of aromatic amine through investigating the reactionsof aromatic amine and peroxide on the premise of analyzing the electrochemical properties of aromatic amine. As a result, the relationship of antidetonating quality and electrochemical properties has been discussed. The research results indicate that p-toluidine and N,N-dimethylaniline has no significant counts. However, the reaction of N-methylaniline and peroxide is the most striking. As a matter of fact, N-methylaniline and aniline and toluidine is generally employed. We have not found any reports that o-toluidine and N,N-dimethylaniline can be used as antiknock. The electrochemical properties of aromatic amine are in line with its’ antidetonating quality and actual application. The study results further indicate that it is feasible that studying the mechanisms of antiknock by making use of the electrochemical properties, which has guiding purpose in seeking new antiknock. Moreover, our work can promote the development of the electrochemical polymerization of aromatic amine.更多还原