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With the development of modern science and technology, the coatings with the single function of anti-corrosion have failed to cover the special requirements in various practical applications. Particularly, the good heat dissipation effect of anti-corrosive coatings is highly demanded in some devices like electrical machinery, heat exchanger and printed circuit board. Here, a facile, eco-friendly, low-cost method is developed to fabricate thermally conductive and anti-corrosive composite coatings by mixing fillers (including boron nitride (BN) and graphene nanoplatelet (GNP)), polyvinyl pyrrolidone (PVP) and waterborne epoxy resin (WER). The hybridization of BN and GNP is used to provide more barriers to delay the penetration of corrosive medium and construct a denser heat conduction network in the composite coatings. PVP is selected as the compatibilizer to further improve the anti-corrosion and thermal conductivity of composite coatings. The effects of filler types and contents on the anti-corrosive and thermally conductive properties are researched. At the loading of 30 wt% BN and 0.5 wt% GNP, the BN@GNP/PVP/WER coating reaches the optimizing anti-corrosive ability, where the |Z| value holds around 6.5 × 109 Ω cm2 after soaking in the corrosive medium for 7 days, and the I corr and E corr values are 1.9 × 10−9 A/cm2 and -0.62742 V, respectively. Meanwhile, this coating displays great heat conduction with the thermal conductivity of 0.87 W/mK at about 30 wt% filler loading. Moreover, the electrical properties and hydrophilicity of coatings at different filler formulations are studied. It is worth noting that the higher electrical conductivity of the coatings at higher GNP content may accelerate the corrosion rate. This study provides a simple route for the design and manufacture of highly anti-corrosive and heat-conducting composite coatings, which exhibits great potential application in next-generation electronic packaging and devices. [ABSTRACT FROM AUTHOR]

Water vapor barrier materials are crucial importance in the packaging industry. Herein, a series of organic–inorganic hybrid coatings are successfully deposited onto polyethylene terephthalate (PET) film through a facile casting method. These coatings impart PET film with enhanced water vapor barrier properties. Particularly, the influencing factors for the water vapor barrier property are systematically investigated in terms of polymers, inorganic fillers and environmental pH level. The results demonstrate that the hybrid coatings comprising ethylene-vinyl alcohol copolymer resin (AQ4104) and inorganic filler with peelable structure, including micas (ME-100 and NTS) and sodium montmorillonite (K–F) significantly reduce the water vapor transmittance ratio (WVTR) of PET film. The WVTR of PET film coated with ME-100/AQ4104 hybrid is 0.7 g m−2/day, which is reduced by 80% than that of uncoated PET film. Also, the composite coatings comprising polyurethane resin (WPB-341) and NTS greatly reduce the WVTR of PET film to 1.0 g m−2/day at 20 wt% NTS content. The inorganic fillers with both small sheet diameter and peelable sheet structure are greatly advantageous for the water vapor barrier property of hybrid coatings. Additionally, the adhesion tests show that these composite coatings possess great adhesion strength, especially for NTS/WPB-341 composite coating of 4.92 N/cm. Moreover, when the environmental pH is adjusted from original alkaline to acidic, the WVTR of PET film coated with AQ4104-based composite coatings is changed, indicating the pH-dependent water vapor barrier ability. This research may provide some reference significance for the simple, low-cost and easy large-scale production of high-performance water vapor barrier coatings for packaging applications. [ABSTRACT FROM AUTHOR]

Anti-corrosion coatings have been widely applied to protect metals against corrosion attacks. To improve the corrosive resistance, it is an effective way to employ porous materials loaded with corrosion inhibitors as fillers of coatings. One of the critical challenges is to advance the inhibitor loading capability of porous fillers. In this study, the mesoporous silica encapsulation is introduced on the ZSM-5 molecular sieves through the hydrolysis-condensation of tetraethyl orthosilicate (TEOS), followed by calcinated for removing the residual templates. The porous SiO 2 @ZSM-5 particles are used as micro-nano containers to load corrosion inhibitor benzotriazole (BTA). The morphologies, structures and BTA releasing behaviors are thoroughly investigated. Subsequently, the as-prepared BTA-SiO 2 @ZSM-5 particles serve as fillers for waterborne epoxy resin (WER) to fabricate BTA-SiO 2 @ZSM-5/WER composite coatings with long-term anti-corrosion property. The corrosive resistance behavior and mechanism are emphatically tested and analyzed. The results demonstrate that the introduction of mesoporous silica on the ZSM-5 molecular sieves significantly increases the specific surface area and pore volume, which is highly beneficial for improving the BTA loading capability of fillers as well as the anti-corrosion performance of coatings. Moreover, the great dielectric, mechanical and UV light-shielding properties of the composite coatings are confirmed. This study presents an effective and practical route for fabricating long-term anti-corrosive composite coatings. [Display omitted] • The mesoporous silica encapsulation is performed through hydrolysis-condensation to improve BTA loading content. • The BTA-SiO 2 @ZSM-5 particles were used to fabricate BTA-SiO 2 @ZSM-5/WER composite coatings with long-term anti-corrosion. • The great dielectric, mechanical and UV light-shielding properties of the composite coatings are confirmed. [ABSTRACT FROM AUTHOR]

In this study, the easy moisture absorption of molecular sieves was addressed by a two-step surface hydrophobic modification process. First, the hydrolysis-condensation of tetraethoxysilane (TEOS) was performed on the pre-treated ZSM-5 zeolite powders to fabricate silica encapsulated ZSM-5 (SiO 2 @ZSM-5) molecular sieves. Second, hydrogen-containing silicone oil (HCSO) was grafted on the surface of SiO 2 @ZSM-5 molecular sieves to prepare hydrogen-containing silicone oil modified silica@ZSM-5 (HCSO-m-SiO 2 @ZSM-5) nanocomposites. After modification, the BET specific surface area of HCSO-m-SiO 2 @ZSM-5 nanocomposite was reduced from 275 to 69 m2 g−1, the pore volume was decreased from 0.27 to 0.05 cm3 g−1, and the average pore diameter was decreased from 4.6 to 2.6 nm. Then, the HCSO-m-SiO 2 @ZSM-5 nanocomposites were used as fillers to endow epoxy resin (EPR) coatings with hydrophobicity. The water contact angle of as-prepared HCSO-m-SiO 2 @ZSM-5/EPR composite coatings reached up to 148° at 30 wt% filler content. Electrochemical analysis shows that the corrosion potential (E corr) of composite coatings was positively shifted from −1.060 to −0.433 V and the corrosion current (I corr) was reduced from 9.0791 × 10−5 to 2.4433 × 10−6 A/cm2 with the increase of filler content from 0 to 30 wt%, demonstrating their enhanced anti-corrosion property. Furthermore, the dielectric, light-shielding and mechanical properties were investigated. The results indicate that the composite coatings perform multifunctions of good hydrophobicity, dielectric performance, anti-corrosion, light-shielding efficiency and mechanical properties, which may have great potential in electronics applications. [Display omitted] • The hydrogen-containing silicone oil modified silica@ZSM-5nanocomposites were prepared through a two-step process. • The as-prepared HCSO-m-SiO 2 @ZSM-5/EPR composite coatings exhibited hydrophobicity with the water contact angle about 148°. • The composite coatings exhibited good dielectric properties and excellent anti-corrosion property. • The composite coatings presented good light-shielding, flexibility and adhesion performances. [ABSTRACT FROM AUTHOR]