氧化430不锈钢膦酸自组装液的溶剂含水量对自组装膜耐点蚀性能的影响

Effect of Water Content in Solvent of Tetradecylphosphonic Acid Self-Assembled Solutions on Pitting Resistance of Self-Assembled Monolayers of Oxidized 430 Stainless Steel

为了弄清膦酸自组装液的溶剂含水量对自组装膜性能的影响,分别以无水乙醇及其与不同含量去离子水的混合液为溶剂配制了十四烷基膦酸自组装液,通过浸泡法在氧化430不锈钢表面制备自组装膜。利用接触角测试、极化曲线、电化学交流阻抗及扫描电镜(SEM)研究了不同溶剂条件下十四烷基膦酸自组装膜的耐点蚀性能。结果表明:随自组装时间延长,膦酸自组装膜覆盖度增大,接触角增加,自组装6 h时得到的自组装膜最致密,接触角最大;溶剂中水有利于形成更致密的自组装膜,随着溶剂含水量增加,膜的耐点蚀能力增强。

Absolute ethyl alcohol and the mixtures of absolute ethyl alcohol with different amounts of distilled water were separately used as solvents to formulate 1-tetradecylphosphonic acid(denoted as TDPA) self- assembled solutions.Resultant TDPA self-assembled solutions were then adopted to prepare TDPA self-assembled monolayers on oxidized 430 stainless steel surface by immersion method.The pitting resistance of TDPA self-assembled monolayers on the oxidized 430 stainless steel was evaluated in relation to contact angle measurement,polarization curve measurement,electrochemical impedance spectrum measurement,and scanning electron microscopic observation.Results showed that the coverage and contact angle of TDPA self-assembled monolayers tended to rise with extending self-assembled duration,and the self-assembled monolayer obtained after 6 h of self-assembly possessed the highest compactness and contact angle.Besides,water in the solvent of TDPA self-assembled solutions was beneficial to forming dense self assembled monolayers,and the pitting resistance of TDPA selfassembled monolayers increased with increasing content of water in the self-assembled solutions.