Polypyrrole-functionalized boron nitride nanosheets for high-performance anti-corrosion composite coating

Boron nitride nanosheet (BNNS) is non-covalently functionalized with polypyrrole (PPy) and incorporated into epoxy for anti-corrosion coating, in which the functionalized BNNS (f-BNNS) exhibits excellent compatibility and dispersibility in the matrix. The f-BNNS0.5-PPy3/EP coating achieved a corrosion rate of 15 nm/year and a high impedance of 1.9 × 107 Ω cm2 after immersion in 3.5 wt% NaCl solution for 40 days, which are 58 times lower and two orders of magnitude larger than those of pure epoxy, respectively. The remarkably improved anti-corrosion activities of f-BNNS0.5-PPy3/EP coating may be mainly ascribed to the homogenous dispersion of insulative and hydrophobic BNNS in the matrix and the synergetic effect of polypyrrole.