Preparing polymeric coatings with well corrosion resistance and high thermal conductivity (TC) to prolong operational life and ensure service reliability of heat conductive metallic materials has long been a substantive and urgent need while a difficult task. Here we report a multifunctional epoxy composite coating (F-CB/CEP) by synthesizing cerium methacrylate and ingeniously using it as a novel curing agent with corrosion inhibit for epoxy resin and modifier for boron nitride through "cation-π" interaction. The prepared F-CB/CEP coating presents a high TC of 4.29 W m K, which is much higher than other reported anti-corrosion polymer coatings and thereby endowing metal materials coated by this coating with outstanding thermal management performance compared with those coated by pure epoxy coating. Meanwhile, the low-frequency impedance remains at 5.1 × 10 Ω cm even after 181 days of immersion in 3.5 wt% NaCl solution. Besides, the coating also exhibits well hydrophobicity, self-cleaning properties, temperature resistance and adhesion. This work provides valuable insights for the preparation of high-performance composite coatings with potential to be used as advanced multifunctional thermal management materials, especially for heat conduction metals protection.© 2023. Shanghai Jiao Tong University.

Heat conduction, electromagnetic compatibility, flame retardancy mechanism, ways to enhance thermal conductivity and multifunctional design including heat conduction, flame retardancy and electromagnetic compatibility for polymer-based composites.

As two-dimensional (2D) materials, graphene and hexagonal-boron nitride (h-BN) are famous for protective coatings, because of their excellent chemical resistance, barrier property, impermeability along with thermal stability, and a large number of these properties are particularly suitable for protective coatings. However, the applications of graphene for metal protection have been limited by galvanic corrosion issues. Also, h-BN nanosheets are also explored as potential materials for corrosion protecting, especially, electrical insulation of h-BN is influential in solving electrochemical reaction and uniquely suitable to be used as an anticorrosion material. Interestingly, graphene doped h-BN exhibit outstanding functionalities in a synergic manner compare to standalone 2D materials. This review provides the fundamental summary of preparation methods for graphene and h-BN, meanwhile, the key challenges and future potential of protective coatings are discussed and predicted.

Alternating hydrostatic pressure (AHP) is the main cause of the marine coating failure of deep-sea tools and equipment. Herein, we synthesized a novel nanostructure, namely, graphene oxide-mesoporous silicon dioxide layer-nanosphere structure loaded with tannic acid (GSLNTA), as a self-healing coating additive. The anticorrosion and anti-AHP performance and the self-healing capability of GSLNTA coating were evaluated through electrochemical impedance spectroscopy, field emission scanning electron microscopy, Fourier-transform infrared spectroscopy, and alternating current scanning electrochemical microscopy (AC-SECM). Results showed that the nanolayer structure of GSLNTA effectively inhibited corrosion mass transmission under simulated deepsea AHP. The nanospheres of GSLNTA released inhibitors to form a ferric tannate film on the exposed metal surface under AHP. The nanolayer and nanosphere of GSLNTA self-healing coating exerted a synergistic effect on anti-corrosion and anti-AHP performance and blocked corrosion factor transmission and coating failure in deepsea applications. AC-SECM revealed the advantages of local impedance complementation of different electrochemical parameters (vertical bar Z vertical bar and -phase) to monitor the self-healing of coatings with GSLNTA. This work also investigated the self-healing performance of alkyd varnish coating embedded with synthetic GSLNTA in protecting steel surfaces. Self-healing materials have an "active healing" capability to prolong the life of organic coatings after unwanted external damage in deep-sea environments.

In this paper, waterborne epoxy (EP) coatings were modified by the incorporation of synthetic structure (DA/meso-TiO2) to improve the anticorrosion ability of waterborne epoxy coatings for steel structures. Fourier transform infrared spectroscopy (FTIR), nitrogen adsorption–desorption, X-ray diffraction (XRD) and thermo-gravimetric analyses (TGA) were used to characterize textural properties of DA/meso-TiO2. Corrosion performances of mild carbon steel coated samples were tested by salt spray tests and employing electrochemical impedance spectroscopy (EIS). FTIR, XRD, TGA and nitrogen adsorption–desorption attested to dopamine polymerization within the mesopores and on the surface of meso-TiO2. The results of EIS and salt spray test showed that the specimen coated with 1.0 wt % DA/meso-TiO2 exhibited optimum corrosion performance among other coating specimens.

In this study, the composite of two-dimensional graphene oxide (GO) nanosheets and button-shaped polyaniline (PANI) was synthesized and further modified by polydopamine (PDA). The obtained PDA-PANI-GO composite was used to enhance the corrosion protection ability of nontoxic water-based alkyd varnish (WAV). The chemical composition, functional groups and surface morphologies of GO, PANI-GO and PDA-PANI-GO composites were characterized by XRD, FT-IR XPS and SEM. The anticorrosion performance was demonstrated by electrochemical impedance spectroscopy measurements and polarization tests. Due to the physical barrier effects and surface hydrophobicity of PANI-GO composite, the approaches of the caustic substances to the surface of the metal was inhibited, while the highly adhesive PDA molecules reinforced compatibility between fillers and WAV. As results, PDA-PANI-GO composite introduced WAV enhanced corrosion prevention performance. Under the optimal conditions, where the ratio of PDA to PANI-GO was kept at 2:1, the impedance values increased by over two orders of magnitude compared with bare steel.Copyright © 2019 Elsevier B.V. All rights reserved.

以Ce(NO₃)₃作为铈源，通过水热合成法在Zr-MOF材料上合成了CeO₂。通过扫描电子显微镜、透射电子显微镜、X射线衍射仪、傅立叶红外光谱仪、X射线光电子能谱仪及比表面积分析仪等对复合材料的微观形貌、组织结构和表面元素组成进行分析。将CeO₂@Zr-MOF作为填料在不同比例下加入环氧树脂涂层中，通过电化学测试、盐雾测试、硬度测试、附着力测试和接触角测试等技术探究涂层的力学性能、疏水性、保护性能和保护机制。结果表明CeO₂成功负载于Zr-MOF上，制备的CeO₂@Zr-MOF形貌规整，颗粒均匀分布，粒径在200 nm左右，具有均匀且致密的孔结构，孔径主要分布在5~20 nm之间，颗粒平均比表面积为99.480 m²/g。CeO₂@Zr-MOF环氧树脂涂层硬度为11HV左右，较纯环氧树脂涂层提高了111.5%左右。涂层附着力为3 MPa左右，较纯环氧树脂涂层提升了18%左右。接触角为70°左右，较纯环氧树脂涂层提升了12°~14°。电化学测试结果表明添加CeO₂@Zr-MOF后的环氧树脂涂层防腐性能明显优于纯环氧树脂涂层。其中添加1%CeO₂@Zr-MOF的环氧树脂涂层在浸泡60 d后低频(0.01 Hz)阻抗模值为5.49 × 10¹⁰ Ω·cm²，比纯环氧树脂涂层高出3个数量级，并且经过400 h的盐雾实验后涂层划痕处几乎没有腐蚀痕迹，表现出对锌镁铝镀层钢板良好的腐蚀防护性能。

A facile and environmentally-friendly method is developed to prepare graphene/waterborne epoxy (WEP) composite coatings. The graphene nanosheets are produced with electrochemical-exfoliation in the solution containing surfactants, cetyl trimethyl ammonium bromide (CTAB) and sodium dodecyl sulfate (SDS). The nanosheets containing solution thus formed are subjected to a quick dialysis and then directly used as a diluent for WEP without any further treatment. This preparation method overcomes the commonly identified problems of aggregations and ‘corrosion promotion’ effect associated with graphene, and increases the impedance of the composite coatings by more than two orders of magnitude. The analysis of anticorrosion performance suggested that the presence of surfactants not only improves the dispersibility of graphene nanosheets but also endows the composite coatings with both barrier and corrosion inhibition capabilities. The strategy reported herein may pave the path to the large-scale production of graphene anticorrosion coatings.