有机防护涂层老化研究进展

New Progress of the Research on Organic Protective Coatings

综述了以聚脲及聚氨酯涂层为代表的有机防护涂层在不同测试方法(SEM、AFM、FTIR、EIS、ATR等)和不同试验环境下的耐老化性能,包括有机防护涂层降解老化研究、腐蚀介质在涂层内的渗透性研究、涂层混凝土氯离子渗透性研究、有机涂层的老化研究及电化学阻抗测试研究。研究结果表明:涂层在不同老化条件下表现出不同的老化行为,紫外线/盐雾循环人工加速老化及Cl-在涂层中扩散最终都能导致涂层形貌破坏,防护功能下降;有机涂层附着力丧失及涂层失效程度可用涂层电容(C)值的迅速增加和涂层电阻(R)值的急剧降低为指标进行衡量。

This paper introduces the achievements of the aging performance on the organic protective coating degeneration aging research through permeable corrosive medium research, coated concrete chloride ion permeability research, the aging research of organic coating and electrochemistry impedance research, related test methods have been introduced too. Research indicated that after 25 weeks and 8 weeks artificial accelerating aging test respectively, the polyurea coating and polyurethane coating was characterized by slightly damaged microstructure and degraded corrosion resistance; in the beginning, the diffusion coefficient of Cl- in protective coating remained at a ratio, once the coefficient grew up to the critical point, the diffusion coefficient of Cl- would increase linearly, however, the coefficient of coated concrete was two or three order of magnitude lower than no treatment samples; the failure effect analysis of the protective coating adhesion could he measured by capacitance of the coating.