Dynamic disulfide-linked vinyl ester nanocomposites for multi-stimuli responsive self-healing anti-corrosion coatings

Abstract

The serious corrosion problems of advanced marine engineering equipment is constraining the implementation of marine potestatem strategy. Graphene modified vinyl ester resin, a new and highly promising composite coating with excellent anti-corrosion, has been widely used in important advance marine equipment. However, their inherent thermosetting cross-linked structures, coupled with the formation of pores and cracks during the curing process, limit their ability to self-heal after mechanical damage, thereby compromising their barrier effectiveness. To address these challenges, this work reports the development of a novel disulfide bond-containing vinyl ester resin by reacting epoxy resin with dithiodipropionic acid. The optimized cured resin exhibits a tensile strength of 50.41 MPa, demonstrates stress relaxation behavior, and possesses physical recyclability at 160 °C under 15 MPa within 30 min, along with heat-induced shape memory properties. Incorporating modified graphene oxide particles into the resin matrix imparts multi-stimuli-responsive self-healing capabilities and introduces a “maze” effect that enhances the coating's protective performance. The resulting composite coatings exhibit efficient scratch healing under various stimuli (i.e., heating, near-infrared (NIR), ultraviolet (UV), and microwave irradiation) and maintain long-term anti-corrosion efficacy, retaining an impedance of 9.38 × 10⁹ Ω cm² after 120 d of immersion in 3.5 wt% NaCl solution. These findings highlight the potential of this advanced coating system for durable protection in marine environments.