A Versatile Approach towards Multifunctional Robust Microcapsules with Tunable, Restorable, and Solvent-Proof Superhydrophobicity for Self-Healing and Self-Cleaning Coatings

Numerous microencapsulation techniques have been developed to encase various chemicals, for which specific processing parameters are required to address the widely differing features of the encapsulated materials. Microencapsulation of reactive agents is a powerful technique that has been extensively applied to self-healing materials. However, the poor solvent compatibility and insufficient thermal stability of microcapsules continue to pose challenges for long-term storage, processing, and service in practical applications. Here, an easily modifiable and highly versatile method is reported for preparing various chemicals filled poly(urea-formaldehyde) microcapsules that exhibit superior tightness against solvents and heat and that possess widely tunable, repetitiously self-restorable, and solvent-proof superhydrophobicity. In addition, the low-cost fabrication of biomimetic multifunctional smart coatings is demonstrated for self-healing anticorrosion and self-cleaning antifouling applications by directly dispersing the superhydrophobic microcapsules into and onto a polymer matrix. The methodology presented in this study should inspire the development of multifunctional intelligent materials for applications in related fields.