Reversible Thermochromic Organosilicon Fibers Based on TiO ₂ @AgI Composites: Preparation, Properties, and Potential Applications

The application of reversible thermochromic fibers (RTFs) is expanding from the smart wearable field toward industrial temperature detection and safety warning; however, most RTFs suffer from low color change temperature thresholds and poor thermal stability, which restrict their applications in medium and high-temperature places (>100 °C). Currently, overheating of equipment is a key factor that causes safety accidents, and the development of reliable visualized temperature warning materials is of great practical significance for accident prevention. To address these issues, TiO₂@AgI is blended with a ternary organosilicon oil spinning solution via a high-temperature air-induced crosslinking method to obtain a reversible thermochromic organosilicon fiber (TSiF) suitable for use in medium and high-temperature environments owing to its thermal stability. Among them, TiO₂@AgI^1.1@SiF-2 has the best performance, showing a significant white to bright yellow color change (color difference ΔE = 25.72) at 135.4 °C. It still possesses the thermochromic performance after 170 cycles and excellent mechanical properties (tensile strength of 9.89-11.33 MPa, no decay in 500 cycles), significant biocompatibility and antimicrobial ability, which fully meets the requirements for medium and high-temperature warning. Thus, this study provides a new idea for fabricating RTFs that can be used for medium and high-temperature warning.