无机富锌涂料中锌粉的改性工艺研究  

Study on the Modification Technology of Zinc Powder in Inorganic Zinc-Rich Coating

作　　者：刘正宇 曾为民[1] 马玉录[1] LIU Zheng-yu;ZENG Wei-min;MA Yu-lu(Key Laboratory of Pressure System Safety Science,Ministry of Education,East China University of Science and Technology,Shanghai 200237,China)

机构地区：[1]华东理工大学承压系统安全科学教育部重点实验室,上海200237

出　　处：《材料保护》2022年第2期81-87,共7页Materials Protection

摘　　要：为了改善无机富锌涂料中片状锌粉分散性差、易团聚、易腐蚀的缺点,通过硅烷偶联剂KH560和硝酸铈对片状锌粉进行表面改性处理,并利用极化曲线测试筛选出锌粉表面改性的最佳工艺条件,对比改性前后锌粉对富锌涂料的物理性能及耐蚀性的变化。结果表明:KH560最佳改性条件是偶联剂用量为12%(质量分数),反应温度为60℃,pH值为8,反应时间为60min;硝酸铈改性锌片/锌粉在反应温度为室温、pH值为7、反应时间为60 min的工艺条件下的最佳用量为0.010%(质量分数)。改性锌粉在水中的分散性得到提升。改性锌粉的施工性、干燥时间、附着力有显著变化。改性锌粉制备的涂层腐蚀电流降低约1个数量级,极化电阻提高约1个数量级,涂层的耐蚀性有明显提高,硝酸铈改性涂层具有最低的钝化电流和最小的腐蚀速率,长效保护建议采用硝酸铈改性锌粉。In order to improve the shortcomings of poor dispersibility,easy agglomeration and easy corrosion of flaky zinc powder in inorganic zinc-rich coatings,the surface of flaky zinc powder was modified by silane coupling agent KH560 and cerium nitrate,and the optimum process conditions for surface modification of zinc powder was screened by polarization curve test.The changes in physical properties and corrosion resistance of zinc powder on zinc-rich coatings before and after modification were compared.Results showed that the optimal modification conditions of silane coupling agent KH560 were 12%(mass fraction),60℃of reaction temperature,pH 8 and 60 min of reaction time.The optimum dosage of cerium nitrate modified zinc flake/zinc powder was 0.01%(mass fraction)under the process conditions of room temperature,pH 7 and 60 min of reaction time.The dispersibility of modified zinc powder in water was improved.Moreover,the workability,drying time and adhesion of the modified zinc powder changed significantly.The corrosion current of the coating prepared by modified zinc powder was reduced by about 1 order of magnitude,the polarization resistance was increased by about 1 order of magnitude,and the corrosion resistance of the coating was significantly improved.In general,the cerium nitrate modified coating had the lowest passivation current and the smallest corrosion rate,which could be recommended to use cerium nitrate modified zinc powder for long-term protection.

关 键 词：无机富锌涂料 片状锌粉 改性 硅烷偶联剂 硝酸铈 腐蚀行为 

分 类 号：TQ630.7[化学工程—精细化工]