| The second-generation low/non-toxic active phosphate pigments, one of the efficient alternatives to the toxic red lead and zinc chromate, have received a great deal of recent attention because of their excellent anti-corrosive abilities. Corrosion inhibitions, possible abate mechanisms of six typical pigments, and antirust mechanisms of two new-engineered pigments are especially studied, based on the second-genenration phosphate antirust pigments in types, preparations, and applications are reviewed. The major studies and conclusions as follows:(1)The electrochemical behaviors of 45# carbon steel electrode were observed in phosphate-doped water extracts with 3.5 % NaCl. The results show that: firstly, more-excelling corrosion inhibitions of Mo-doped zinc phosphate AlZnPO4MoO4?4H2O (shorted as No.35 ) and Mo-doped aluminou polyphosphate AlZn2P3O10(MoO4)2·2H2O (shorted as No.36), taking inhibite anode reactions as the principal things, were revealed in different pH values. Secondly, high-performances were also obtained in ZPA-doped and ZMP-doped acidic and neutral systems, but not in basic conditions. Finally, pefect results were indicated in basic systems with traditional pigments of APW-I.(2)Good effects were acquired in four neutral conditions of phenolic resin, rosin-modified phenolic resin, Chlorinated rubber anti-corrosive topcoat, and epoxy zinc-rich compound coating with ZMP. Especially, more-excelling stabilizations and corrosion inhibitions were showed in chlorinated rubber and epoxy zinc-rich systems together with ZPA. Furthermore, the study of phosphate pigments applied in mixed resin, with 210# rosin-modified phenolic resin and phenolic resin, have achieved anticipate, particularly in later stabilizations.(3)The P-Mo heteropolyanions with better oxidation behaviors were formed by molybdate-phosphate composite pigments. Combination with the polyphosph–ate to be more excellent passive protective film, effectively impeding the spread of aggressive media.
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