Highly effective anti-corrosion composite coatings enhanced by non-covalent functionalized boron nitride nanosheets via a facile latex approach

Boron nitride nanosheets (BNNSs)/polymer composite coatings with highly effective corrosion resistance have promising applications in metal surface protection. However, BNNSs tend to aggregate in waterborne polymer matrix, which degrades anticorrosion. Herein, a facile and effective method was developed to fabricate a stable latex containing non-covalently modified BNNSs through in situ polymerization of styrene in emulsion system, and waterborne polyurethane (WPU) composite coatings were sequentially constructed for the purpose of corrosion protection via latex blending. The developed composite coating (BNNSs@PS/WPU) exhibited a significantly improved impedance by 4 orders of magnitude after 28 days of immersion compared with pure WPU coating. Such outstanding anti-corrosion properties can be ascribed to the comprehensive action of BNNSs@PS composite latex, of which the PS microspheres can not only effectively prevent BNNSs from coalesce, but also act synergically with BNNSs that effectively retard the permeation of corrosive medium to the metal surface. [Display omitted] •A stable composite latex containing non-covalent modified BNNSs was obtained.•PS not only restrain the aggregation of BNNSs but also delay the permeation of corrosion medium.•The composite coating showed superior corrosion resistance due to the synergism of PS and BNNSs.•Latex blending was used to prepare BNNSs/polymer composite coatings.