Evaluation and failure analysis of linseed oil encapsulated self-healing anticorrosive coating

• Published in: Progress in organic coatings Vol. 118; pp. 108 - 115
• Main Authors: Wang, Haoran, Zhou, Qixin
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 01.05.2018; Elsevier BV
• Subjects: Anticorrosion; Corrosion; Corrosion prevention; Drying agents; Electrochemical impedance spectroscopy; Failure analysis; Linseed oil; Microcapsule; Microcracks; Microencapsulation; Protective coatings; Self healing materials; Self-healing coating; Self-healing coating; Anticorrosion; Microcapsule; Linseed oil
• ISSN: 0300-9440; 1873-331X
• DOI: 10.1016/j.porgcoat.2018.01.024

[Display omitted] •Self-healing coating was prepared by adding microcapsules into an epoxy coating.•Intact self-healing coating exhibits excellent barrier property as epoxy coating.•Intact self-healing coating has higher water-uptake than intact epoxy coating.•Scratched self-healing coating has excellent healing and anticorrosion ability.•The failure reason of scratched self-healing coating was proposed and discussed. In this study, a linseed oil encapsulated self-healing coating was developed by incorporating 10 wt% synthesized microcapsules into an epoxy-polyamine coating matrix. The linseed oil encapsulated polyurea-formaldehyde (PUF) microcapsules had ∼80 wt% core content with ∼80 um diameter. The influence of embedded microcapsules on the anticorrosive property of the self-healing coating had been studied by electrochemical impedance spectroscopy. The intact self-healing coating exhibited excellent anticorrosive property as the intact pure epoxy coating, although the addition of microcapsules into the epoxy matrix resulted in a higher water-uptake. The scratched self-healing coating showed excellent healing ability and corrosion inhibition function for microcracks, but it still cannot recover the barrier property as good as the intact coating. The failure of the scratched self-healing coating had been analyzed and the possible reason may be the formation of conductive pathways at the interface between the linseed oil film and the epoxy matrix and/or PUF microcapsule shell.