A modified epoxy resin is prepared from dimer acid (EJS),1,6-hexanediol-diglycidylether (1,6-HDE) and bisphenol A type epoxy resin(ES1) wherein Both EJS and 1,6-HDE has long aliphatic flexible chain segments.The flexibility and impact resistance of the prepared epoxy resin was improved,meanwhile,the viscosity was reduced.The reaction temperature,mol ratio of ES1,1,6-HDE and the amount of catalyst have been optimized.The modified resin is characterized by FT-IR,GPC and other means.The performance of the resin is tested by DSC,stress-strain tensile test,impact test and flexibility test.The results showed that the modified resin toughness was significantly increased:the elongation at break was as high as 42.9％,the impact strength reached to 70 cm,and the flexible reached to Level 1.The anticorrosive primer formula was designed by using the modified resin as main filmforming material.The anticorrosion properties of the primer were studied through the electrochemical,salt fog experiment,chemical immersion and salt flooding immersion.The results showed that dimer acid modified epoxy resin coating had excellent anticorrosion performance:EIS impedance dropped slowly,salt fog resistance,immersion of 3.5％ NaC1 (aq) and 10％ NaOH (aq) were more than 4 000 h respectively,meanwhile,the depth of cathodic disbonding unilateral stripping was 1.8 mm.%利用二聚酸(EJS)羧基与环氧基团的反应,向双酚A型环氧树脂(E51)中引入1,6-已二醇二缩水甘油醚(1,6-HDE)及二聚酸中的脂肪长链柔性链段,以提高环氧树脂的柔韧性和耐冲击性,并降低其黏度.通过优化反应温度、E51与1,6-HDE的物质的量比、催化剂用量,制备出了高柔韧性环氧树脂.采用红外光谱、凝胶色谱等手段对改性树脂进行了表征,采用差示热扫描量热、应力-应变拉伸试验、冲击实验等手段对合成树脂的性能进行了测试.结果表明:改性树脂的柔韧性明显增加,断裂伸长率42.39％,清漆漆膜耐冲击性70 cm,柔韧性l级.以改性树脂为主要成膜物质,设计了防腐底漆配方,并对涂层的防腐性能进行了研究.结果表明:二聚酸改性环氧树脂涂层具有优异的防腐性能,EIS阻抗下降缓慢,耐盐雾性、耐盐水性和耐碱性较优,阴极剥离单边剥离深度为1.8 mm.
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