用分子连接性方法研究曼尼希碱缓蚀剂的构效关系

A Study on Relation Between Molecular Structure and Performance of Some Mannich's Base Corrosion Inhibitors by Using Molecular Connectivily

介绍了分子连接性方法的基本概念、分子连接性指数的表达式和计算。计算了有缓蚀性能文献数据的4种曼尼希碱(DEAP,PDPP,PAMCH和PAP)的分子连接性指数。对于这4种曼尼希碱,缓蚀性能(20号钢试片70℃和90℃时在加入0.1%提纯曼尼希碱化合物的20%盐酸溶液中的腐蚀速率)与分子连接性指数的0阶项之间无线性关系,引入对于苯环和取代基的修正项后,获得了70℃和90℃下腐蚀速率与分子连接性指数之间的拟合非线性方程,相关系数R2分别为0.975和0.980。利用这2个方程对CHAP的缓蚀性能进行了预测,预测值与文献实验值的相对误差分别为0.6%和3.7%。认为分子连接性方法可用来研究缓蚀剂的构效关系。图2表2参9。

The fundamental concept, the expressions, and the calculation of molecular connectivity (MC) are presented. Some MC indexes are calculated for 5 Mannich's bases, namely: DEAP, PDPP, PAMCH, CHAP, and PAP, for which the corrosion inhibitory capacity can be found in literature where else. It is shown that there exists no linear relationship between the corrosion rate data at 70℃ and 90℃ (of carbon steel in 20% hydrochloric acid with 0.1% one of the purified Mannich's bases added) and the zeroth term of MC index function of these compounds. By introducing a correction term for benzene ring and replacing group, two non-linear equations are established by fitting the corrosion rate value to the MC index data at 70℃ and 90℃, respectively, with correlation coefficient >0.98. By using these equations the corrosion inhibition by CHAP is predicted with the errors relative to the published experimental corrosion rate data of 0.6% and 3.7%, respectively. The molecular connectivity is considered to be an effective tool for understanding the structure/performance relationship of corrosion inhibitors.