纳米容器改性环氧涂层对Q235碳钢的防腐蚀性能

Anticorrosion Performance of Epoxy Coating Modified with Nanocontainers

以纳米SiO_2为载体,采用层层自组装技术在其表面交替沉积天然聚电解质壳聚糖和环保型缓蚀剂聚天冬氨酸,制备出纳米容器,将纳米容器分散到环氧涂层中获得改性环氧涂层。通过Zeta电位、扫描电子显微镜(SEM)和Fourier转换红外线光谱仪(FT-IR)对纳米容器进行了表征,利用电化学阻抗技术对比研究了普通环氧涂层与改性环氧涂层/Q235碳钢体系在3.5%(质量分数)NaCl溶液中的腐蚀行为。结果表明,纳米容器可以有效减缓海水在环氧涂层内部的扩散,提高环氧涂层的电阻,从而增大腐蚀反应阻力;改性后涂层的电化学阻抗在浸泡120 h后仍维持在105Ω·cm2以上,耐蚀性显著增强。

Nano-containers were synthesized via layer by layer （LbL） self-assembly technique with SiO2 as core and alternative layers of chitosan and polyaspartic acid inhibitor as shell. Then nano-contain- ers modified epoxy coatings were prepared and applied on carbon steel Q235. The nano-containers were characterized by means of Malvern laser particle size analyzer, Fourier transform infrared spectroscopy （FT-IR） and scanning electron microscope （SEM）. In addition, the electrochemical behavior of epoxy coat- ings/Q235 systems with and without nano-containers in 3.5% （mass fraction） NaCI solution were investi- gated through electrochemical impendence spectroscopy （EIS）. Results indicated that the corrosion resis- tance of epoxy coatings had been greatly increased by the incorporating nano-containers, which can ef- fectively reduce the diffusion of water in coating matrix and enhance the coating impedance for corrosion reaction. The impedance value of the modified epoxy coating may be maintained by above 105 Ω·cm^2 even after 120 h immersion, revealing the enhanced anticorrosion performance.