A novel organic-inorganic two-dimensional filler for composite coating with excellent mechanical and high-pressure CO2 anti-corrosion performance

Abstract

organic-inorganic composite fillers were successfully prepared by a simple one-pot film-like coating of poly (α-cyanoethyl acrylate) (PECA) on mica. Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), and thermogravimetric analysis (TG) were used to analyze the structure, morphology, and chemical composition of the organic-inorganic composite filler and pure mica in detail. The organic-inorganic composite filler was added to epoxy resin to prepare a composite coating with long-lasting anti-corrosion and wear-resistance properties. The composite coating was characterized by electrochemical impedance spectroscopy (EIS), high-pressure CO2 corrosion tests, friction performance tests, differential scanning calorimetry (DSC), and adhesion performance tests. The mechanical test results showed that the average wear quality of the EP/P30&M(8/2) composite coating prepared with the modified filler was reduced to 65.7 % of that of the EP/MICA(8/2) coating. The addition of the modified filler to the coating substantially improved the wear resistance and crosslinking of the composite coating, reduced the porosity, increased the density, and effectively improved the overall performance of the composite coating. The results of high-pressure CO2 corrosion tests in harsh environments and electrochemical impedance spectroscopy showed that the composite coating had excellent barrier capacity. After high-pressure CO2 corrosion tests, the EP/P20&M(9/1) composite coating still has a high impedance modulus value of 6.348 × 1010 Ω/cm2 at 0.01 Hz, which is 5 orders of magnitude higher than that of the pure epoxy coating, and showsed excellent long-lasting corrosion resistance in EIS tests. This study provides new ideas for the industrial application of mica and the preparation of long-lasting anti-corrosion coatings.