Polyurea as a reinforcing filler for the anti-corrosion and wear-resistant application of epoxy resin

Highly dispersed nanofibers with continuous strengthening interface can enhance the anticorrosion and wear resistance of traditional waterborne epoxy resin. Here, the polyurea nanofibers with ~50 nm in diameter were synthesized by addition polymerization of methylene diphenyl diisocyanate and organic amine. Good wettability signifies a continuous tightly reinforced interface in the coating. Good dispersed polyurea nanofibers at 0.25 wt% can effectively fix micro-defects for achieving the best barrier performance, which lengthens even restrains the corrosion diffusion path of electrolyte. The impedance of as-prepared composite coating is increased by almost four times, providing long-lasting protection even in harsh environments. Meanwhile, the polyurea nanofibers with 0.25 wt% can greatly improve the wear resistance of coating up to 73.2 %, indicating that the inevitable wear in service has been dealt well. The anti-wear capacity of composite coating is derived from the entangled polyurea nanofibers transmitting the force of the contact surface and dimensional resistance to prevent coating displacement. Herein, this work presents a promising application of polyurea nanofibers to enhance the anti-corrosion and wear resistance of epoxy resin. • Nanoscale fibrous polyurea with a diameter of ~50 nm was successfully synthesized. • The optimal addition amount of polyurea nanofibers at 0.25 wt% significantly reduces the microdefects of coating. • The polyurea nanofibers can greatly improve the wear resistance of coating via decreasing wear rate by 73.2 %. • Polyurea nanofibers can block the penetration of corrosive medium into the substrate.