Homeostatic Microfiber-Composed Synthetic Leathers with Chemical Robustness and Undercooling Self-Regulation

Homeostatic microfiber leathers with temperature self-regulation promise broad applications, ranging from the apparel and automotive interior industries to the home furnishing and healthcare industries. Temperature self-regulation is achieved by phase-change materials containing microcapsules introduced within the leathers. The introduction of phase change microcapsules (PCMs) into microfiber leather faces two formidable challenges: (1) the shell of microcapsules must remain chemically stable against alkalis and organic solvents; (2) PCMs possess the ability to reduce supercooling during which latent heat is released, allowing for the precise and controllable release of latent heat. Here we present a high-performance homeostatic microfiber-composed synthetic leather containing PCMs that can address these two challenges, which not only demonstrate exceptional chemical robustness under alkaline conditions but also offer efficient and precise control over temperature fluctuation and latent heat release by reducing supercooling. Titanium carbide (TiC) known for its high thermal conductivity and alkali resistance has been selected as the shell material for the microcapsules, which can effectively resolve chemical stability issues. Meanwhile, the high thermal conductivity of TiC can be leveraged to enhance heterogeneous nucleation, thus narrowing the temperature range for latent heat release. The resultant microfiber leather shows outstanding capabilities for adjustable thermal energy storage. Our studies offer an effective approach to create homeostatic microfiber-composed synthetic leathers with chemical robustness and undercooling self-regulation, which would be useful in the fields of the textile, biomedical, and healthcare industries.