Epoxy Powder Clearcoats Used for Anticorrosive Purposes Cured with Ytterbium III Trifluoromethanesulfonate Available to Purchase

New low-curing-temperature epoxy powder coatings cured cationically using ytterbium III trifluoromethanesulfonate (Yb[TfO]₃ or ytterbium triflate) as the initiator were 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 of anticorrosive properties (electrochemical impedance spectroscopy [EIS], electrochemical accelerated test [AC/DC/AC], and salt fog spray) have been used together with an adherence test to establish the optimal system. Results show that a system using 1 phr (parts of initiator per hundred of resin, w/w) of ytterbium triflate presents good anticorrosive properties. The technique AC/DC/AC has shown its ability to evaluate properly, much faster, and in accordance with anticorrosive property results of powder coatings obtained by other techniques.