A methodology to enrich epoxy coatings of an effective self-healing feature on wet surfaces was developed as a further step on for practical corrosion protection issues. To this aim, a polyetheramine was chemically engineered by grafting catechol units and then successfully encapsulated in microcapsules (MCs) to be finally embedded into an epoxy resin deposited on steel panels. Fourier transform infrared spectroscopy (FTIR), thin-layer chromatography, and 1D and 2D nuclear magnetic resonance spectroscopy confirmed the successful polyetheramine modification by dopamine units. Different dosages of catechol-modified polyetheramine were encapsulated within poly(styrene-co-acrylonitrile) shell via electrospray method to study the influence of dopamine grafting on the healing performance. Scanning electron microscopy (SEM) analysis revealed the formation of the spherical MCs, while FTIR and TGA analyses confirmed the successful encapsulation. The highly responsive self-healing coatings were then prepared by embedding amine- and isocyanate-containing MCs (1:1 weight ratio; 3 wt% overall) as a dual-capsule system exploiting the polyurea formation as a fast healing reaction. In operando electrochemical impedance spectroscopy (EIS) tests were employed to study the underwater self-healing performance. According to the EIS results, monotonically increasing variation with time of the charge transfer resistance was correlated with a fast and effective underwater self-healing performance for the sample using 40 wt% of a catechol-modified healing agent. Such results, combined with others including SEM investigation on the underwater healed samples, point to an improved adhesion of the growing dopamine-bearing polymer to both underlying metal and epoxy edges of the scratch.

A highly responsive healing agent for the autonomous repair of anti-corrosion coatings on wet surfaces. In operando assessment of the self-healing process / M.S. Koochaki, S.N. Khorasani, R.E. Neisiany, A. Ashrafi, S. Trasatti, M. Magni. - In: JOURNAL OF MATERIALS SCIENCE. - ISSN 0022-2461. - 56:2(2021 Jan), pp. 1794-1813. [10.1007/s10853-020-05332-9]

A highly responsive healing agent for the autonomous repair of anti-corrosion coatings on wet surfaces. In operando assessment of the self-healing process

S. Trasatti
Penultimo
;
M. Magni
Ultimo
2021

Abstract

A methodology to enrich epoxy coatings of an effective self-healing feature on wet surfaces was developed as a further step on for practical corrosion protection issues. To this aim, a polyetheramine was chemically engineered by grafting catechol units and then successfully encapsulated in microcapsules (MCs) to be finally embedded into an epoxy resin deposited on steel panels. Fourier transform infrared spectroscopy (FTIR), thin-layer chromatography, and 1D and 2D nuclear magnetic resonance spectroscopy confirmed the successful polyetheramine modification by dopamine units. Different dosages of catechol-modified polyetheramine were encapsulated within poly(styrene-co-acrylonitrile) shell via electrospray method to study the influence of dopamine grafting on the healing performance. Scanning electron microscopy (SEM) analysis revealed the formation of the spherical MCs, while FTIR and TGA analyses confirmed the successful encapsulation. The highly responsive self-healing coatings were then prepared by embedding amine- and isocyanate-containing MCs (1:1 weight ratio; 3 wt% overall) as a dual-capsule system exploiting the polyurea formation as a fast healing reaction. In operando electrochemical impedance spectroscopy (EIS) tests were employed to study the underwater self-healing performance. According to the EIS results, monotonically increasing variation with time of the charge transfer resistance was correlated with a fast and effective underwater self-healing performance for the sample using 40 wt% of a catechol-modified healing agent. Such results, combined with others including SEM investigation on the underwater healed samples, point to an improved adhesion of the growing dopamine-bearing polymer to both underlying metal and epoxy edges of the scratch.
Self-healing coatings; Microcapsules; Catechol; Corrosion protection; In operando electrochemical impedance spectroscopy
Settore CHIM/07 - Fondamenti Chimici delle Tecnologie
Settore CHIM/02 - Chimica Fisica
Settore CHIM/05 - Scienza e Tecnologia dei Materiali Polimerici
gen-2021
22-set-2020
Article (author)
File in questo prodotto:
File Dimensione Formato  
Koochaki2021_Article_AHighlyResponsiveHealingAgentF.pdf

accesso aperto

Descrizione: Manoscritto pubblicato
Tipologia: Publisher's version/PDF
Dimensione 3.61 MB
Formato Adobe PDF
3.61 MB Adobe PDF Visualizza/Apri
Pubblicazioni consigliate

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/2434/781739
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 22
  • ???jsp.display-item.citation.isi??? 19
social impact