对甲苯磺酸掺杂聚吡咯的合成、表征及其对金属镁的防腐蚀性能研究  

Synthesis and Characterization of Polypyrrole Doped by p-Tolyl Sulfonic Acid and Its Anticorrosion Property for Magnesium

作　　者：李倩倩[1] 黄健涵[1] 刘素琴[1] 关鲁雄[1] 黄可龙[1] 

机构地区：[1]中南大学化学化工学院,长沙410083

出　　处：《化学学报》2008年第5期571-575,共5页Acta Chimica Sinica

基　　金：国家自然科学基金(No.20376086);教育部博士点基金(No.20030533001)资助项目

摘　　要：以对甲苯磺酸为掺杂剂,三氯化铁为氧化剂,化学氧化吡咯制备了对甲苯磺酸掺杂聚吡咯.考察了掺杂剂与氧化剂的用量对掺杂聚吡咯电导率的影响,得到了高电导率聚吡咯的优化条件,用UV,IR和SEM对其结构和形貌进行了表征.结果表明,n(对甲苯磺酸)∶n(吡咯)∶n(三氯化铁)=0.75∶1∶0.5时,合成的聚吡咯的形貌规则,电导率达42.7S·cm-1.以聚吡咯为功能成分,环氧树脂为成膜物质,得到一种功能膜,旋涂于金属镁表面,采用极化曲线和开路电位考察了含有聚吡咯的膜层对金属镁的防腐蚀性能.结果表明,含有聚吡咯的膜层对金属镁有很好的防腐蚀性能,腐蚀电流为0.0981A,腐蚀电位为-0.88V,在膜层与金属镁之间形成了一层钝化膜.Polypyrrole doped by p-tolyl sulfonic acid was chemically synthesized from pyrrole using ptolyl sulfonic acid as a doping agent and ferric chloride as an oxidant. The effect of dosage of the doping agent and the oxidant on the conductivity of doped polypyrrole was investigated, and the optimized condi- tions were obtained, The molecular structure of the polypyrrole was characterized by UV and IR spectra, and its morphology was studied by SEM. The results indicated that the polypyrrole was regular, and its conductivity reached 42.7 S·cm^-1, when the ratio of n（p-tolyl sulfonic acid） ： n（pyrrole） ; n（ferric chloride）= 0.75 ： 1 ： 0.5. A film containing the polypyrrole was prepared on magnesium surface, and its anticorrosion property was investigated by potentiodynamic polarization curves and open circuit potentia/. It was found that the polypyrrole showed an excellent anticorrosion property for magnesium, the corrosion current and voltage were measured to be 0.0981 A and -0.88 V, respectively, and a passivation layer was formed between the film and magnesium surface.

关 键 词：对甲苯磺酸 聚吡咯 掺杂 电导率 防腐蚀 

分 类 号：O633.5[理学—高分子化学] TG174[理学—化学]