Preparation of chitosan-reduced graphene oxide microcapsules
An actual paper describes the reparation of chitosan-reduced graphene oxide (CS-RGO) microcapsules and its application in self-healing coatings.
During the study, self-healing coatings healed by the synergistic action of ultraviolet light and moisture were developed. Firstly, a polysiloxane-based healing agent, containing acryloyloxy (CH2=C(CH3)COO-)and methoxy silane(-SiOCH3)groups, is synthesised and encapsulated in chitosan-reduced graphene oxide (CS-RGO) microcapsules with compact CS-RGO shell structures. The CS-RGO microcapsules containing the polysiloxane core are then embedded in epoxy-modified silicone resin to achieve efficient self-healing coatings.
Improved mechanical properties
As the CS/GO ratio increase, the reduction degree of GO, the sphericity of the CS-RGO microcapsules, and the average diameter all increase. Moreover, the compact CS-RGO shell formed by the assembly and stacking GO sheets as well as the interactions between CS and GO helps to maintain effectiveness of the core and stability of the microcapsules. The result shows that embedding of the CS-RGO microcapsules in the resin matrix improves the mechanical properties and anti-corrosion properties of the matrix.
According to the developers, the self-healing coatings with the UV/moisture dual healing mode is beneficial for achieving superior self-healing effects, which is promising for various industries, especially the over-water construction of ships, bridges, pipelines, etc.
The study has been published in Progress in Organic Coatings, Volume 151, February 2021.
