Epoxy/nanopigment coatings: Preparation and evaluation of physical-mechanical properties

In this research, new hybrid epoxy/nanopigment coatings were prepared and their physical and mechanical properties were studied. For this purpose, blue hybrid dye-clay nano-pigments (DCNPs) were synthesized by using the cationic exchange reaction between methylene blue (MB) and an organically modified clay (Cloisite 15A, C15A). Thereafter, blue color epoxy formulations were prepared by the incorporation of DCNPs into an epoxy system. In addition, two common organic and inorganic pigments (namely, C.I. pigment blue 15:2 and C.I. pigment blue 28) were used to prepare two common blue color epoxy resins as reference samples. Finally, the physical and mechanical performances of these coatings were evaluated and compared with each other. Different techniques including CHNS, XRD, TEM, DMTA, QUV accelerated weathering tester and spectrophotometry were used in this study. The results showed that the dispersion and interaction/exfoliation of DCNPs in epoxy matrix were better than those of C15A. Moreover, it was found that the color characteristics and mechanical properties of the epoxy/nanopigment coatings were superior compared to those of reference coatings.