Self-repairing superhydrophobic microfiber leather leveraging light-triggered release of actives

Microfiber-composed functional synthetic leather is of particular interest because it owns the advantages of good fluffiness, softness, excellent hygroscopicity, the random three-dimensional bundle structure similar to that of natural leather, which grants excellent moisture permeability, air permeability, chemical resistance, waterproof and mildew resistance, and various functions. Typically, the microfiber of functional synthetic leather is obtained through splitting the original sea-island fiber by solvent-induced dissolution and etching of its sea phase, which inevitably leads to the decline of the wettability of the treated leather. Herein, light-triggered functional microcapsules for self-healing wettability of split microfibers have been judiciously designed and developed. These functional microcapsules loaded with fluoroalkyl silane, which are used to coat onto the original sea-island fiber, allow for photocontrol of releasing the superhydrophobic chemical to the coated fibers. Despite the superhydrophobicity of the split fiber would be weakened by the splitting operation, the light-triggered release of fluoroalkyl silane can effectively amend its superhydrophobic properties. The microfiber leather self-repaired by the functional microcapsules exhibits good superhydrophobic performance, excellent self-cleaning ability to dust and RhB solution, high friction resistance (up to 200 rubs), and good UV light self-repairing cycle performance. This study provides a versatile solution for efficiently self-repairing microfiber leathers after the splitting process.