Materials Chemistry and Physics, Vol.204, 282-293, 2018
Synergistic effect of nanosize and irradiation on epoxy/conducting poly(o-phenyldiamine) nanospheres composite coatings: Synthesis, characterization and corrosion protective performance
Nano conducting polymers (CPs) dispersed coatings have emerged as leading coating system, which have proved to be an effective alternative to the cariconegenic chromate coatings. Cps have emerged as nontoxic anti corrosive pigments also known as "green primers/fillers". Here, we report microwave synthesis (MW) of conducting Poly(o-phenyldiamine) (PDA), following seven principles of "green chemistry" approach. This includes less hazardous chemical synthesis, atom economy, prevention, safer solvents, design as energy efficient process, reduction of side products and remarkably, eco-friendly nature. The use of aqueous medium during synthesis process proved to be green, renewable and free from harmful VOCs. We have also analyzed the effect of MW irradiation on various properties of Poly(o-phenyldiamine)(mPDA) and its comparison with conventionally polymerised PDA(cPDA). The FT-IR, TEM, SEMEDX, and four probe conductivity measurements were performed to analyze and account the influence of MW irradiation on the morphology, size, solubility and electrical properties. The mPDA dispersed epoxypolyamide (mPDA-epoxy) formulated coatings, showed superior coating properties than cPDA-epoxy nanocomposite coatings. The salt spray test and potentiodynamic polarization (PDP) studies were also conducted in pH = 9, 11 and 14, revealed that mPDA-epoxy coatings exhibited excellent corrosion resistance as compared to cPDA-epoxy. The superior physico-mechanical properties and corrosion protection performance of mPDA-epoxy confirmed our speculation of using MW for the synthesis of CPs and their use in varying applications. (C) 2017 Elsevier B.V. All rights reserved.
Keywords:Poly(o-phenyldiamine) nanoparticles;Green approach;Microwave synthesis;Electrochemical corrosion;Epoxy