Self-healing coatings based on poly(urea-formaldehyde) microcapsules
A recently published paper portrays the situ polymerisation, the properties and the application of a self-healing coating based on poly(urea-formaldehyde) microcapsules.
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Protective coating failure can lead to excessive substrate wear increasing the need for maintenance. Polymeric microcapsules loaded with a healing agent can offer self-healing properties when embedded to a coating, repairing the microcracks produced.
Good self-healing ability
Epoxy loaded microcapsules with a poly(urea-formaldehyde) shell were successfully prepared within the current study, using in situ polymerisation. Microcapsules were obtained as colorless free-flowing powder with a diameter ranging from 37 to 66 μm and high encapsulation efficiency (up to 75%). Microcapsule characteristics, such as morphology, particle size, encapsulation efficiency, thermal stability, were correlated to in situ polymerisation conditions, and efficiently induced self-healing ability to an alkyd-based coating.
The study has been published in Progress in Organic Coatings, Volume 161, December 2021.