Ce3+掺杂聚苯胺中空微球/环氧涂层防腐蚀研究

聚苯胺作为一种新型的防腐蚀材料,在钢铁防腐蚀领域具有良好的应用前景.通过自组装法在聚(2-丙烯酰胺基-2-甲基丙磺酸)(PAMPS)水溶液中制备了聚苯胺(PANI)中空微球,将稀土Ce~(3+)掺杂到聚苯胺中空微球表面制备了一种新型的Ce~(3+)掺杂修饰的聚苯胺中空微球(PANI-Ce~(3+)).以PANI-Ce~(3+)中空微球为防腐填料添加到环氧树脂(EP)中,制备Ce~(3+)掺杂修饰的聚苯胺中空微球/环氧(PANI-Ce~(3+)/EP)防腐涂层.采用FT-IR、UV-Vis、SEM、XRD等对PANI-Ce~(3+)中空微球进行表征,通过动电位极化法、交流阻抗测试探究PANI-Ce~(3+)/EP涂层的防腐蚀性能.结果表明:PANI-Ce~(3+)/EP涂层具有较高的腐蚀电压(Ecorr=-0.414 V)和较小的腐蚀电流密度(I_(corr)=0.676×10~(-5)μA/cm~2);PANI-Ce~(3+)/EP涂层低频区阻抗模量随浸泡时间呈现先减小后增大的变化趋势,在质量分数3.5%的NaCl水溶液中经过1 680 h腐蚀后,阻抗模量保持在106.6Ω·cm~2;表面有划伤的PANI-Ce~(3+)/EP涂层在质量分数3.5%的Na Cl水溶液进行1 680 h腐蚀实验后,涂层表面不起泡,仅在划痕处有少量铁锈.PANI-Ce~(3+)/EP涂层表现出优异的耐腐蚀性能.

Anticorrosion study of epoxy coating with Ce3+ doped polyaniline hollow microspheres

As a kind of novel anticorrosion materials, polyaniline (PANI) exhibits great potentials in the field of steel anticorrosion. PANI hollow microspheres were fabricated by self-assembly method in poly (2-acrylamido-2-methylpropanesulfonic acid) ( PAMPS) aqueous solution. After then, Ce3+ ions were loaded onto PANI to prepare Ce3+ doped PANI (PANI-Ce3+) hollow microspheres. PANI-Ce3+hollow microspheres were employed as functional additives and dispersed in epoxy resin ( EP ). Structure and morphology of PANI-Ce3+ hollow microspheres were characterized by Fourier transform infrared spectroscopy ( FT-IR ) , scanning electron microscopy ( SEM) , X-ray diffraction ( XRD) and transmission electron microscopy ( TEM) etc. Electrochemical impedance spectroscopy ( EIS ) and potentiodynamic polarization test were employed to analyze anticorrosion performance of PANI-Ce3+/EP coatings explored in 3.5wt.％ NaCl aqueous solution for 1680 hours. Tafel plots showed that PANI-Ce3+/EP coating exhibited high corrosion potential ( Ecorr=-0.414 V) and small corrosion current density (Icorr=0.676×10-5μA/cm2). In addition, Bode plots showed that impedance in low frequency region decreased firstly and then increased with soaking time. Impedance values were maintained at 106.6Ω?cm2 explored in 3.5wt.％ NaCl aqueous solution for 1680 hours. Meanwhile, no blister was observed and corrosion just occurred around the scratches after PANI-Ce3+/EP coatings with scratches on the surface were explored in 3. 5wt.％ NaCl aqueous solution for 1680 hours, indicating their excellent anticorrosion performances.