Abstract
Polyurea/poly(urea–formaldehyde)/Al2O3 hybrid microcapsules with a dense Al2O3 nano-layer containing 4,4′-methylenebis cyclohexyl isocyanate (HMDI) have been successfully fabricated via combaning Atomic layer deposition (ALD) process and interfacial/in-situ polymerization process. This dense Al2O3 nano-layer can be controllable deposited in the form of a single atom film through continuous self-limiting reactions of Al(CH3)3 and H2O on the surface of the PU/PUF microcapsules at a temperature range of 120–180 °C. The formed hybrid microcapsules showed a monodispersed diameter of ~60 µm with a controlled and nano-sized Al2O3 shell. Moreover, the deposited Al2O3 nano-shell significantly increased the thermal stability and mechanical property of hybrid microcapsules, which could maintain their integrity under harsh conditions. In addition, by embedding hybrid microcapsules into an epoxy matrix, an excellent anticorrosion performance in scratched coatings via self-healing functionality was obtained. Therefore, the formed hybrid microcapsules with enhanced thermal stability and mechanical property via ALD process could promote their practical application in self-healing composites.
Original language | English |
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Article number | 148561 |
Number of pages | 8 |
Journal | Applied Surface Science |
Volume | 542 |
Early online date | 5 Dec 2020 |
DOIs | |
Publication status | Published - 15 Mar 2021 |
Externally published | Yes |
Funding
This work was supported by the financial support from the Fundamental Research Funds for the Central Universities (ZYGX2019J023) and the startup funds from the University of Electronic Science and Technology of China (Y030202059018003 , Y03019023601008001).
Keywords
- AlO nano-layer
- Anticorrosion performance
- Atomic layer deposition
- Hybrid microcapsules
- Self-healing composites