抗渗复合聚氨酯涂层的制备及其防腐性能研究

Preparation and Anticorrosive Properties of Impermeable Composite Polyurethane Coatings

海洋大气环境下金属腐蚀严重,在该环境下的金属表面施加涂层防护尤为重要。将二维片层状氧化石墨烯与TiO_(2)/SiO_(2)纳米粒子复合制备聚氨酯涂层,并对比研究了采用超声和高能球磨处理的聚氨酯复合涂层对碳钢的防腐行为。在50℃条件下进行28 d的5%NaCl中性盐雾实验后,结果显示,与未防护的碳钢对比,高能球磨处理的涂层试样表面未出现明显锈蚀,涂层对金属起到了良好的防护效果。2种处理方法得到的聚氨酯复合涂层在低频阻抗的模值|Z|0.01 Hz提升了约3个数量级,腐蚀电流密度降低了近4个数量级,且高能球磨比超声处理得到的复合涂层的阻抗模值高2个数量级,腐蚀电流也明显降低。

Metal corrosion in marine atmospheric conditions is severe.Therefore,it is necessary to apply coating to surfaces of metal in this en⁃vironment.In this research,two⁃dimensional lamellar graphene oxide was combined with TiO_(2)/SiO_(2)nanoparticles to prepare polyurethane coat⁃ings.The anticorrosive behavior of the polyurethane composite coating treated with ultrasonication and high energy ball milling on carbon steel was evaluated.Results showed that after 28 d neutral salt spray test with 5%NaCl at 50℃,the surface of the coating samples treated with high⁃energy ball milling did not exhibit significant corrosion,in contrast to the unprotected carbon steel,indicating that the coating had a good protective effect on metal.The polyurethane composite coatings obtained from two treatment methods exhibited an increase of approximately three orders of magnitude in the modulus of low⁃frequency impedance|Z|0.01 Hz,and a nearly fourfold decrease in corrosion current density.Moreover,the impedance modulus of the composite coating produced by high⁃energy ball milling was two orders of magnitude higher than that obtained by ultrasonic treatment,and the corrosion currents were significantly lower.