Investigation On The Corrosion Behavior Of Two Dimensional Materialsi/Self-Healing Organic Coatings

The polymer-based anti-corrosive coating is the most widely used among all anti-corrosion measures.The physical shielding ensures that the corrosive medium such as water molecules,oxygen and ions are isolated from the metal matrix,thus effectively avoiding corrosion electrochemical reactions.In complex and variable marine environments,the inherent defects of the anti-corrosion coating and the defects generated during preparation and practical application will affect the life span of the coating and even accelerate the corrosion rate of the metal with defects.Therefore.the development of intelligent anti-corrosion coating with self-healing function is the key to solve this problem.The purpose of this paper is to develop intelligent composite-based hybrid organic anti-corrosion coatings that adapt to the changing marine environment,control the efficient release of active substances,and have good self-healing capabilities.In this paper,two-dimensional nanosheet materials are used to coat different corrosion inhibitor to form a nanosheet structure,which is then distributed into the organic coating.Once the coating is defective,the composite nanosheet system releases the corrosion inhibitor and initiates the repairing process.The specific research content and conclusions are as follows:(1)The sulfonated polyaniline-layered double hydroxide(LDH)/waterborne epoxy composite is prepared by the polymerization of the aniline and aminobenzenesulfonic acid by the pre-intercalation agent aminobenzenesulfonic acid in the LDH layer.We explored the corrosion resistance of the composite coating.It has been found that the defects of the water-based epoxy coating modified by sulfonated polyaniline-LDH and were effectively reduced.and the addition amount of 1.0 wt%makes the coating have significant corrosion protection performance.(2)By fixing and intercalating poly(3,4-ethylenedioxythiophene)-polystyrene sulfonic acid(PEDOT:PSS)in the layer and the structure of LDH,and then using electrostatic interaction with graphene oxide to assemble.We compared the c-LPG and i-LPG samples.The composite coating c-LPG has anti-corrosion properties and self-healing capability.It has been found that the active materials prepared by the blending method not only avoid the micro-galvanic corrosion of graphene,but also cause cross-linking of PEDOT:PSS to repair the coating defects.(3)An intermediate layer having a releasing effect was prepared by filling the corrosion inhibitor benzotriazole(BTA)into the mesoporous silica-graphene oxide nanosheets.In addition,the organic resin was used as a topcoat to obtain a bi-layered anticorrosive coating.Through connection of the intermediate layer,the interfacial bonding of the coating is effectively improved.We also investigated the release kinetic model;the responsive release of the corrosion inhibitor effectively enhanced the corrosion resistance and had a self-repairing function.