MODIFIED GRAPHENE AND GRAPHENE NANOPLATELET FOR ANTI-CORROSION COATINGS
A graphene-based zinc containing coating is provided to prevent or slow down the corrosion of steel. The graphene-based materials are selected from a group of modified single-layer graphene, double-layer graphene, few layer graphene, graphene nanoplatelet, doped graphene, and a combination thereof. The modified graphene-based materials in zinc-containing paints or coatings act as a barrier to prevent or slow down the diffusion of corrosive species to the steel surface to be protected. For such a purpose, the graphene has a high aspect ratio and good structural integrity, especially a lack of defects on the basal plane of the graphene.
1 . A graphene-based and zinc containing anti-corrosion paint or coating comprising:
a graphene-based material;
a sacrificial zinc metal or compound; and
a resin where the resin contains the graphene-based material and the sacrificial zinc metal or compound.
2 . The paint or coating of claim 1 wherein the graphene-based material is made from mechanically or chemically exfoliated from graphite and functionalized with oxygen or other functionalities so that the paint or coating does not electrochemically corrode steel.
3 . The paint or coating of claim 1 wherein the graphene-based material is one or more of graphene, bi-layer graphene, few layer graphene, graphene nanoplatelet, functionalized graphene, doped graphene, and a combination thereof.
4 . The paint or coating of claim 1 wherein the resin comprises one or more of epoxy, polyurethane, acrylic, alkyd, and other polymeric compounds.
5 . The paint or coating of claim 1 wherein the graphene-based material is functionalized by one or more of functional groups selected from epoxide, carbonyl, carboxyl, hydroxyl, and amine.
6 . The paint or coating of claim 1 wherein the graphene-based material is modified by grafting a polymer to an edge or a surface of the graphene-based material.
7 . The paint or coating of claim 1 wherein zinc is present as zinc metal, zinc compound, or a combination thereof.
8 . The paint or coating of claim 1 wherein the graphene-based material is present with an oxygen content of 2-20 atomic percent.
9 . The paint or coating of claim 1 wherein the graphene-based material is present with an oxygen content of 4-15 atomic percent.
10 . The paint or coating of claim 1 wherein the graphene-based material is present with an oxygen content of 5-10 atomic percent.
11 . The paint or coating of claim 1 wherein the graphene content in a formulation of the paint is in the range of 0.1-10 weight percent.
12 . The paint or coating of claim 1 wherein the graphene content in a formulation of the paint is in the range of 0.5-5 weight percent.
13 . The paint or coating of claim 1 wherein the graphene content in a formulation of the paint is in the range of 0.5-1 weight percent.
14 . The paint or coating of claim 1 wherein the zinc content in a formulation of the paint is in the range of 20-90 weight percent.
15 . The paint or coating of claim 1 wherein the zinc content in a formulation of the paint is in the range of 30-60 weight percent.
16 . The paint or coating of claim 1 wherein the zinc content in a formulation of the paint is in the range of 30-50 weight percent.
17 . The paint or coating of claim 1 wherein the zinc content in a formulation of the paint is in the range of 20-90 weight percent.
18 . A method of forming the paint or coating of claim 1 , the method comprising:
mixing the graphene-based material, the sacrificial zinc metal or compound, and
the resin to form the paint or coating; and
wherein the graphene-based material is first dispersed in a solvent to form a dispersion or a wet cake.
19 . A method of forming the paint or coating of claim 1 , the method comprising:
mixing the graphene-based material, the sacrificial zinc metal or compound, and
the resin to form the paint or coating; and
wherein the graphene-based material is a dry powder.
20 . The method of claim 18 further comprising applying the paint or coating to a steel structure.