High-efficiency graphene/epoxy composite coatings with outstanding thermal conductive and anti-corrosion performance

Although graphene is an ideal thermal conductive and anti-corrosion filler, the thermal conductivity and corrosion resistance of graphene/polymer composite coatings are difficult to improve synergistically. Herein, graphene (rGO) and benzotriazole-loaded hollow mesoporous silica (BTA@HMS) were mixed into epoxy to simultaneously improve its thermal conductivity and anti-corrosion performance. The results show that the thermal conductivity of the prepared rGO-BTA@HMS/epoxy composite coating reaches 1.239 W/(m·K), which is improved by 596 % over pure epoxy. The corrosion protection property of the composite coating is four orders of magnitude higher than that of pure epoxy. Furthermore, BTA@HMS can significantly inhibit the accelerated corrosion of the copper metal coated by rGO/epoxy composite coatings through its self-healing function, and the charge transfer resistance for substrate corrosion is increased from 60 KΩ·cm2 to 3410 KΩ·cm2 due to the introduction of BTA@HMS. The prepared composite coatings have the potential for applications in thermal conductive and anti-corrosion coating fields.