高屏蔽耐温酚醛环氧重防腐涂料的制备及性能研究

针对大型海水淡化关键设备制造成本高、防腐期效短等问题,基于金属表面屏蔽阻隔原理,采用酚醛改性环氧树脂和改性聚酰胺为基料,以氧化铁红、硫酸钡、片状填料等为防腐填料,获得应用于新型低合金耐蚀钢或碳钢基材表面的高屏蔽耐温酚醛环氧重防腐涂料。实验结果表明:该涂料吸水率1. 2%,抗氯离子渗透性0. 9×10-3mg/cm²·d,柔韧性1 mm,耐冲击性50 cm,耐88℃海水浸泡6 000 h,耐盐雾10 000 h,涂层耐阴极剥离性能测试被剥离涂层距人造漏涂孔外缘平均距离为4. 5 mm,经33 d 88℃海水浸泡0. 01 Hz低频阻抗(|Z|0. 01 Hz)条件下该涂层电化学交流阻抗值由8. 28×1010Ω·cm²降为1. 18×108Ω·cm²,且曲线平滑,说明该涂层具备优异的防腐性能。

Study on Preparation and Properties of Effective Barrier and Heat Resistant Phenolic Epoxy Heavy-Duty Anticorrosive Coatings

Regarding the high cost of manufacturing and shorter service life of large desalination key equipment,based on the principle of barrier for electrochemical corrosion of metal,a phenolic modified epoxy resin and modified polyamide were used as basic materials,with iron oxide red,barium sulfate and flake fillers to prepare the effective barrier and heat resistant phenolic epoxy heavy-duty coatings for the new low alloy corrosion resistant steel or carbon steel substrate.The experiment results showed that the coatings provided water absorptionrate 1.2%,chloride ion permeability 0.9×10^-3 mg/cm^2 d,flexibility 1 mm,impact resistance 50 cm,water immersion resistanceat 88℃6000 h,salt spray 10000 h,stripping distance of 4.5 mm in cathodic disbonding test,and the electrochemical impedance values under the condition of 0.01 Hz low frequency impedance(|Z|0.01 Hz)after 33 days of immersion in sea water at 88℃dropped from 8.28×10^10Ω·cm^2 to 1.18×10^8Ω·cm^2,with as mooth EIS curve,which indicated the excellent anticorrosive properties of the coatings.