Multifunctional Epoxy Nanocomposites for Improved Mechanical Properties for Surface Coating Applications

The nanocomposite surface coating film samples were prepared by high-speed mechanical mixing of novolac epoxy resin (EEW 180 eq/gm) and a varying amount of nano-CaCO3 (0–5 wt%) for 30 min. Further, these mixtures were used to cast 100 microns films on the metal/glass panels and subjected to cure at 110o C for 1 h and post-cure at 80 oC for 5 h. The nanocomposite surface coating film samples were tested for mechanical properties (viz. impact resistance, scratch hardness, adhesion, and flexibility) and resistance to artificial seawater (ASW). It was observed that 4 wt% nano-CaCO3 containing film sample showed maximum impact strength, scratch hardness, adhesion, and flexibility, and resistance to ASW compared to neat epoxy and other nanocomposite film samples. The curing behavior of nanocomposite film samples was analyzed by DSC.  The reactivity effect of nano-CaCO3 blending on epoxy resin by FTIR spectroscopy, morphological studies by SEM, and surface gloss by Triglossometer were also investigated.