Effect of boron nitride modified by sodium tripolyphosphate on the corrosion resistance of waterborne epoxy coating

In this work, h-BN@STPP was successfully obtained by facile co-modification of sodium tripolyphosphate (STPP) and silane coupling agent (KH-550) on h-BN nanosheets, with waterborne epoxy coatings incorporated for metallic substrate corrosion protection. Results showed that the impedance modulus at the lowest frequency (Z(f)(=)(0.1 Hz)) of h-BN@STPP composite coating increased three orders of magnitude in comparison with neat waterborne epoxy coating, exhibiting outstanding corrosion resistance. The reinforced anticorrosion performances of h-BN@STPP composite coatings could be attributed to the "labyrinth effect" of h-BN and passivation effect of STPP on the metal substrates.