Thermal induced intrinsic self‐healing in epoxy based elastomer coatings provided by disulfide metathesis reactions

Abstract

Self-heal epoxy coatings have been prepared using sulfur-sulfur metathesis reaction as an intrinsic method for inducing self-healing property. Inducing of the self-healing property was carried out via insertion of the 3,3 0 -dithiodipropionic acid as chain extender functionalized with bisphenol A diglycidyl ether.According to the results, the prepared coatings were capable to recover their mechanical properties after damage and heal their surface as well. Noticeably, the healing yield of the coatings was about 43% and 76% for the samples containing 0.5 and 1.0 equivalents of chain extender, respectively. Furthermore, the mechanical properties of the self-heal coating were modified in the presence of the disulfide bonds from 0.22 MPa to 1.25 MPa. Regarding to the increment of the crosslinking density due to the presence of the sulfur containing chain expender, the average molecular weights between crosslinkings was reduced from 43.75 Â 10 3 g mol À1 in epoxy sample to 4.61 Â 10 3 g mol À1 in sulfur containing sample. The proposed facilitate method for inducing the self-healing property make it applicable to a wide range of epoxy coatings.

Self‐healing characteristics of superabsorbent polymers in epoxy coating for corrosion inhibition of carbon steels

“…Intrinsic self‐healing coatings are capable of healing via self‐reactions, while extrinsic self‐healing coatings require the addition of self‐healing components in the coating system for the healing to occur 3 . An example of intrinsic self‐healing coating was investigated by Eidi and Pedram 4 where an epoxy‐based elastomer coating's self‐healing property was carried out through disulfide metathesis reaction and the self‐healing is triggered by the application of heat. On the other hand, common methods where extrinsic self‐healing coating is implemented use capsules impregnated with corrosion inhibitors or vascular‐based healing.…”

Preparation and Properties of Multiple Dynamic Crosslinked Poly(siloxane‐urethane)

“…If timely remedial measures are not taken, structural damage to the material may occur, potentially leading to safety risks and significantly reducing its service life. [6][7][8][9][10][11][12][13] Therefore, incorporating self-healing capabilities into polyurethane materials is considered a viable solution to mitigate these limitations.…”

“…Additionally, in complex and harsh usage environments, traditional polyurethane materials are prone to scratches and mechanical cuts over their lifespan. If timely remedial measures are not taken, structural damage to the material may occur, potentially leading to safety risks and significantly reducing its service life [6–13] . Therefore, incorporating self‐healing capabilities into polyurethane materials is considered a viable solution to mitigate these limitations.…”

Epoxy-Based Catalyst-Free Self-Healing Elastomers at Room Temperature Employing Aromatic Disulfide and Hydrogen Bonds

“…Materials meeting only one of these requirements are classified as vitrimer-like materials, and this study developed vitrimer-like self-healing materials with the disulfide bond in this respect. Among the vitrimer or vitrimer-like materials, many researchers have tried to develop self-healing vitrimers with the disulfide bond, − which is because the disulfide bond reaction is facile to fabricate and promises high self-healing efficiency. Most of the self-healing materials with disulfide bonds, however, require external stimuli such as light, − heat, − catalyst, − pH, and pressure …”

“…Among the vitrimer or vitrimer-like materials, many researchers have tried to develop self-healing vitrimers with the disulfide bond, − which is because the disulfide bond reaction is facile to fabricate and promises high self-healing efficiency. Most of the self-healing materials with disulfide bonds, however, require external stimuli such as light, − heat, − catalyst, − pH, and pressure …”