Synergistic effect of polyvinylpyrrolidone noncovalently modified graphene and epoxy resin in anticorrosion application

Abstract

In this article, polyvinylpyrrolidone (PVP) was used for the noncovalent modification on the surface of graphene. Compared with covalent modification, this method maintained the original structure of graphene layers, thereby maximizing the original properties of graphene. The π–π noncovalent bond was formed between PVP and graphene by X-ray photoelectron spectroscopy analysis, indicating that PVP successfully modified graphene. The thickness of graphene layer was measured by atomic force microscopy, which showed that the distance between graphene layers was increased by 5–6 nm, and the stability of the modified graphene in N, N-dimethylformamide was remarkably improved. The obtained composite coating by combination of the modified graphene and the epoxy resin was subjected to electrochemical impedance test to obtain the best anticorrosive effect of the coating with the graphene content of 0.3 wt%. The results showed that the addition of graphene to the epoxy resin could effectively improve the anticorrosive effect. Meanwhile, the good electrical conductivity allowed the electrons which lost from the substrate to led to air or saline rapidly, thereby reducing the combination of iron ions with oxygen and the generation of corrosion products (iron oxides).

High-damping polyurethane-based composites modified with amino-functionalized graphene

“…8 The techniques used for modifying the GNP surface mainly include chemical functionalization (covalent bonding) and physical modification (noncovalent bonding; that is, π/π-interaction-based bonding), with the former being more effective. [9][10][11] In the chemical modification of GNP, reactive functional groups such as isocyanic acid, hydroxyl, carboxyl, and amino groups are introduced to the GNP surface to induce covalent bonding between the modified GNP and polymer matrix. Covalent GNP-polymer bonding can enhance the GNP-polymer interactions in the composite and improve the dispersibility of GNP in the polymer matrix.…”

Effects of polyvinylpyrrolidone as a dispersant agent of reduced graphene oxide on the properties of carbon fiber-reinforced polymer composites

“…The use of non-covalent modifiers in graphene/ epoxy system has several advantages including their harmless chemistry, easy availability, and no damage to sp 2 network of graphene compared to covalent ones. 24,25 Polyvinylpyrrolidone (PVP), as a largely reported non-covalent modifier, provides a good distribution of relatively high concentrations of graphene in the epoxy matrix without agglomerations, improving the adhesion between graphene filler and epoxy. 16,25,26 Wajid et al 20 prepared graphene/ PVP/epoxy composites by using both solution processing and freeze-dry/mixing methods.…”

“…24,25 Polyvinylpyrrolidone (PVP), as a largely reported non-covalent modifier, provides a good distribution of relatively high concentrations of graphene in the epoxy matrix without agglomerations, improving the adhesion between graphene filler and epoxy. 16,25,26 Wajid et al 20 prepared graphene/ PVP/epoxy composites by using both solution processing and freeze-dry/mixing methods. In both cases, the addition of 1 wt.% PVP-stabilized graphene into epoxy composites improved the Young's modulus, tensile strength, and increased the glass transition temperature because of the strong interfacial adhesion between the epoxy and PVPmodified graphene nanosheets.…”