Multifunctional Composite Membrane with Temperature and Sweat Management as well as Fluorescent Indication for Human Health

Smart temperature-regulating textiles play a crucial role in protecting human health during outdoor activities in high-temperature environments. However, the design of smart temperature-regulating materials and the visual monitoring and management of sweat still present significant challenges in the development of smart temperature-regulating textiles. Herein, a multifunctional composite membrane material with temperature-regulating and sweat management functions has been successfully prepared by incorporating a polymer-based phase change temperature-regulating material (amino-modified poly(methyl vinyl ether-alt-maleic anhydride)-g-(poly(ethylene glycol) monomethyl ether)) and micronano organic rare earth luminescent fibers with pH-responsive functions. Since polylactic acid and cellulose acetate were chosen as the fiber-forming polymers, the as-prepared multifunctional composite membranes possess good biocompatibility. The multifunctional composite membrane can absorb heat within the temperature range of 25 to 40 °C to regulate human body temperature; the fastest absorption temperature is 38.1 °C, and the enthalpy of phase change is 42.71 J/g. Simultaneously, due to the presence of many polar functional groups in the molecular structure of phase change materials, the multifunctional composite membrane can rapidly absorb sweat on the human body surface to ensure the comfort of the human body in a high-temperature environment. The incorporation of a benzoate rare earth luminescent material enables the multifunctional composite membrane to have the ability to monitor sweat visually. By observing the change in fluorescence intensity after the multifunctional composite membrane absorbs sweat, fluorescent indication of the human body’s health status during exercise may be provided. Additionally, the mechanical properties and reusability of the multifunctional composite membrane provide essential conditions for its wide range of applications.