交流阻抗法评价氟改性乙烯基酯树脂的耐腐蚀性

Evaluation of corrosion resistance of fluorine-modified vinyl ester resins by electrochemical impedance spectroscopy

用甲基丙烯酸十二氟庚酯(DFHMA)对乙烯基酯树脂(VERs)进行共固化改性,采用FT-IR和XPS分析了固化物结构及表面性能,并采用交流阻抗(EIS)分析了不同氟含量的树脂涂层在质量分数为3.5%NaCl溶液中浸泡不同时间的交流阻抗谱,进行了等效电路、孔隙率及吸水率分析。结果表明,含氟乙烯基酯树脂固化后,氟元素在树脂表面富集;树脂涂层的阻抗值随氟含量的提高而逐渐增加;当DFHMA质量分数为7%时阻抗值达到最高,且其孔隙率和吸水率均较未改性树脂涂层低;经DFHMA改性的VERs具有良好的抗渗透性和耐蚀性。

Dodecafluoroheptyl methacrylate（DFHMA） has been used to modify vinyl ester resins（VERs）.The structure and surface properties of the cured resins were analyzed by Fourier transform infrared spectroscopy（FTIR） and X-ray photoelectron spectroscopy（XPS） respectively.The AC impedance spectroscopy of VERs coatings with different contents of DFHMA immersed in 3.5% NaCl solution for different times was studied by electrochemical impedance spectroscopy（EIS）,and the equivalent circuit,porosity,and water absorption were analyzed.The results indicated that the fluorine was localized on the surface of the cured fluorine-modified vinyl ester resins（FVERs）.The impedance value increased gradually with increasing content of DFHMA,reaching a maximum for FVERs containing 7% DFHMA mass fraction.The porosity and water absorption of FVERs were lower than the corresponding values for unmodified VERs.The results showed that VERs modified by DFHMA had good impermeability and corrosion resistance.