纳米ZnS增强聚苯胺复合涂层的性能研究

Anticorrosive Performance of Nano ZnS Reinforced Polyaniline Coatings on Q235 Carbon Steel

采用水热法制备纳米Zn S,与化学氧化法制备的聚苯胺(PANI)按不同比例混合,制得纳米Zn S改性PANI复合物,将其涂覆于Q235碳钢表面制备复合涂层。采用SEM,AFM,XRD和FTIR表征纳米Zn S改性PANI复合涂层的表面形貌和结构,利用动电位极化和EIS研究复合涂层浸泡在3.5%(质量分数)Na Cl溶液中的腐蚀电化学行为。结果表明,纳米Zn S改性PANI复合涂层中Zn S和PANI二者均匀分散,显著提高其耐蚀性能。当Zn S和PANI的质量比为1∶1时,性能最优,在3.5%Na Cl溶液中浸泡7 d,复合涂层的保护效率高达99.9%;浸泡30 d后复合涂层的表面形貌发生变化,仍为致密的保护膜,对基底材料具有较好的保护作用,使其免受溶液离子的侵蚀。

Nano-ZnS was prepared by hydrothermal method and polyaniline was prepared by chemical oxidation respectively, which then were blended to prepare a series composite materials of polyaniline modified by nano-Zn S. Finally the relevant composite coatings were applied on Q235 carbon steel. The acquired composite materials and coatings were characterized by scanning electron microscopy（SEM）, atomic force microscopy（AFM） and X-ray diffraction（XRD） and Fourier transform infrared spectroscopy（FTIR）. The electrochemical corrosion performance of the composite coatings in 3.5%（mass fraction） Na Cl solution was investigated by potentiodynamic polarization and electrochemical impedance. The results showed that the nano- Zn S was uniformly dispersed in the polyaniline matrix and therewith the anticorrosive performance of the coatings was improved significantly. Among others the coating with 50%（mass fraction） Zn S exhibited the best anticorrosive performance with a protection efficiency 99.9% after immersion in 3.5% Na Cl solution for 7 d. Besides, after immersion for 30 d, the coating surface morphology changed obserious-ly, but the coating is still dense and could provide good protectiveness for the substrate material even up to 30 d.