Studies of Corrosion Resistant Properties of PU Coatings Reinforced with La-Pr-O Nanostructures

This work examines the main parameters to obtain solid solutions of La-Pr-O nanostructures and their incorporation into a poly(urethane) (PU) based on hexamethylene diisocyanate (HDI) (PU-HDI). The effect of obtaining La-Pr-O at different intervals of time was evaluated. Structural results indicated that the alloys, as solid solutions, can be obtained during the first 60 min. These nanostructures were found to have morphologies of agglomerates growing from random and irregular shapes of particles. Once stablished the optimal conditions, 1, 3, and 5 wt.% of La-Pr-O nanostructures were incorporated into PU-HDI through magnetic stirring and deposited onto AISI 1060 carbon steel by spray technique. XRD indicated that the nanostructures were successfully dispersed into PU-HDI with a final reduced crystal size related to the adequate dispersion. The electrochemical findings, such as the displacement in the Ecorr towards to positive direction, an important reduction of the jcorr and polarization resistance, demonstrate that La-Pr-O nanostructures offer an effective strategy to improve barrier properties of PU systems.