Repeatable Self-Healing of a Protective Coating Based on Vegetable-Oil-Loaded Microcapsules

Abstract

Generally, microcapsule-based self-healing materials have the limitation of single local self-healing. A few studies have reported repeatable self-healing in these microcapsular materials, but there is a challenge to develop multi-cycle self-healing materials that have the advantages of easier preparation and a more efficient operation. In this work, a mixture of two vegetable oils, soybean and olive oil, was used as a healing agent. The atmospheric oxygen-induced reaction behavior (in the presence of a catalyst) was investigated for various compositions of the vegetable oil mixtures; infrared spectroscopy, recovery testing, and viscoelasticity measurement were performed to find an optimum composition of the healing agent. Microcapsules loaded with soybean oil and catalyst-containing olive oil were separately prepared and used to prepare a dual-capsule self-healing coating. It was demonstrated through optical and scanning electron microscopy that, upon scribing the self-healing coating, the vegetable oils flowed out from microcapsules to self-heal the damaged area. When the healed area of the self-healing coating was re-scribed, self-healing was repeated, which was confirmed by scanning electron microscopy (SEM) and anticorrosion and electrochemical testing. Our new repeatable self-healing coating provides the merits of easy preparation, no need for external intervention such as light irradiation, and an environmentally-friendly nature.

Self-healing polymers for surface scratch regeneration

“…Recently, while facing the challenge of one-time self-healing Chung's group developed vegetable oil-loaded self-healing microcapsules that can heal twice on repeat after inflicting a wound. 40…”

Electrically Functional Self‐Healing Polymers: Design, Assessment, and Progress

“…[9,10] Moreover, the polymers can also be multi-functionalized to meet specific requirements. [11][12][13] The self-healing process in microcapsule-based self-healing materials typically involves three sequential steps: [14] i) microcapsule rupture and release of liquid healing agents, ii) chemical reaction between healing agents, which flow into the damaged area upon capillary forces, and the material matrix, and iii) cross-linking of polymer networks to blunt and repair cracks (Figure 2a).…”

Sustainable smart anti-corrosion coating materials derived from vegetable oil derivatives: a review

“…Since mid of the 1900s, petroleum-based polymers have been widely used in the coating industry; however, from the environmental point of view, it is high time we shi towards renewable resources. [1][2][3] The major challenge in today's emerging world is the replacement of conventional petroleumbased polymers with renewable polymers, where vegetable oils (VOs) are potential starting materials among other bio-based Poonam Singh is presently pursuing her PhD degree from University of Petroleum and Energy Studies (UPES), Dehradun, India. She has received her bachelor degree in Chemistry from Zakir Husain Delhi college (University of Delhi), New Delhi, India followed by Post Graduation diploma in Nanotechnology from Maitreyi College (University of Delhi), New Delhi, India.…”

“…46,47 However, polymeric coatings derived from vegetable oils perform poor chemical and thermal resistance as compared to petroleum-based polymeric coating. 48 To enhance the thermal and mechanical properties including preventing the moisture/water penetration, a wide range of nanollers have been incorporated into the coating matrix. 5,13,[49][50][51] Carbonized materials such as carbon nanotubes (CNTs), graphene, and mesoporous carbon structures have been attracted to researchers due to their chemical, thermal, electrical, and mechanical properties, thus, leading towards the enhancement of mechanical, anti-corrosion, antimicrobial properties.…”

“…Since mid of the 1900s, petroleum-based polymers have been widely used in the coating industry; however, from the environmental point of view, it is high time we shift towards renewable resources. 1–3 The major challenge in today's emerging world is the replacement of conventional petroleum-based polymers with renewable polymers, where vegetable oils (VOs) are potential starting materials among other bio-based renewable substances like cellulose, starch, sugar, etc. 4–6 Vegetable oils are the centre of attention owing to their favourable chemical structure, availability, cost, and unsaturated sites for functional group fabrication, thus advantageous for designing the molecules from scratch.…”