水性锈转化涂料的制备及性能

采用苯丙乳液与改性苯丙乳液共混作为成膜物质,以单宁酸为转锈剂,柠檬酸为配位剂,焦性没食子酸为转锈促进剂,再加入成膜助剂、有机胺类缓蚀剂、渗透剂等,制备了一种可应用于带锈钢材的水性锈转化涂料。通过正交试验和单因素试验确定了涂料的最优配方为:成膜物质65%,转锈剂5%,转锈促进剂2%,缓蚀剂0.6%,渗透剂2%,配位剂0.5%,成膜助剂1.6%,蒸馏水余量。采用塔菲尔极化曲线测量、中性盐雾试验和盐水浸泡试验考察了漆膜的耐蚀性。结果表明,所制水性锈转化涂膜可耐盐雾96 h,耐盐水浸泡168 h,且耐酸性较强,在pH为2的3.5%NaCl溶液中有保护作用。与两款市售涂料相比,该自制水性锈转化涂料具有更好的耐蚀性。

Preparation and properties of waterborne rust conversion paint

A waterborne rust conversion paint applied to rusted steel substrates was prepared with the mixture of styrene-acrylic emulsion and modified styrene-acrylic emulsion as binder,tannic acid as rust converter,citric acid as complexing agent,pyrogallic acid as rust conversion accelerator,as well as other constituents such as film-forming auxiliary agent,amine inhibitor,and penetrating agent.The optimal formulation of the paint was determined by orthogonal test and single factor experiment as follows:binder 65%,rust converter 5%,rust conversion accelerator 2%,corrosion inhibitor 0.6%,penetrating agent 2%,complexing agent 0.5%,film-forming auxiliary agent 1.6%,and distilled water balance.The corrosion resistance of the coating obtained therefrom was studied by Tafel polarization curve measurement,neutral salt spray test,and saline immersion test.The results showed that the waterborne rust conversion coating could endure neutral salt spray test for 96 hours and saline immersion for 168 hours.It also had a protection efficacy in 3.5%NaCl solution at a pH of 2,showing good acid resistance.The home-made waterborne rust conversion paint had better corrosion resistance than two types of commercially available counterparts.