A wide variety of inhibitive pigments is now being offered as possible alternatives to chromate and lead compounds for painted metals protection. Unfortunately, the most wide spread of these substitute pigments, zinc ...A wide variety of inhibitive pigments is now being offered as possible alternatives to chromate and lead compounds for painted metals protection. Unfortunately, the most wide spread of these substitute pigments, zinc phosphate, has, at present, raised some environmental concern because phosphate causes the eutrophication of water courses and zinc itself is toxic. The aim of this re-search was to study the anticorrosive performance of a mixture consisting of zinc phosphate, modified zeolite and clay （bentonite） in order to diminish phosphate content in paints. The zeolite and the clay were exchanged with La（III） ions, as inorganic green inhibitor. In the first step, the anticorrosion protection by La（III） ions in solution was assessed by electrochemical tests. In the second step, an epoxy-polyamide paint formulated with the pigment mixture applied on galvanized panels was studied by salt spray test and electro-chemical noise measurements （ENM）. The results showed that it was possible to replace part of the zinc phosphate content in the paint with the exchanged zeolite and the clay.展开更多
基金Project supported by CONICET(Consejo Nacional de Investigaciones Científicas y Técnicas)UNLP(Universidad Nacional de La Plata)CICPBA(Comisión de Investigaciones Científicas de la Provincia de Buenos Aires)
文摘A wide variety of inhibitive pigments is now being offered as possible alternatives to chromate and lead compounds for painted metals protection. Unfortunately, the most wide spread of these substitute pigments, zinc phosphate, has, at present, raised some environmental concern because phosphate causes the eutrophication of water courses and zinc itself is toxic. The aim of this re-search was to study the anticorrosive performance of a mixture consisting of zinc phosphate, modified zeolite and clay （bentonite） in order to diminish phosphate content in paints. The zeolite and the clay were exchanged with La（III） ions, as inorganic green inhibitor. In the first step, the anticorrosion protection by La（III） ions in solution was assessed by electrochemical tests. In the second step, an epoxy-polyamide paint formulated with the pigment mixture applied on galvanized panels was studied by salt spray test and electro-chemical noise measurements （ENM）. The results showed that it was possible to replace part of the zinc phosphate content in the paint with the exchanged zeolite and the clay.
