Application of electrochemical techniques to study the effect on the anticorrosive properties of the addition of ytterbium and erbium triflates as catalysts on a powder epoxy network

New low curing temperature epoxy powder coatings cured with o-tolylbiguanide and catalyzed by the use of erbium(III) and ytterbium(III) trifluoromethanesulfonates have been formulated. Their curing kinetics and anticorrosive properties have been studied and compared with a system commonly used in industry (o-tolylbiguanide/epoxy resin). Three different tests for measuring anticorrosive properties (EIS, AC/DC/AC, and salt fog spray) have been used together with an adherence test, in order to establish the ideal system. Results show that a system using 1 phr of ytterbium triflate presents good anticorrosive properties. The technique AC/DC/AC has shown its ability to evaluate properly and much faster than other techniques the anticorrosive properties of powder coatings with similar results.