Three-in-One: AIEgen End-Labeling of CO₂ Polymer for Visible Fiber Thermometer

Abstract

Visual temperature sensors are of great significance for environmental management and industrial process control. Herein, we developed a visual sensing approach based on fiber fluorescent imaging by configuring aggregation-induced emission (AIE)-functionalized CO2-based poly­(propylene carbonate) (PPC). A three-in-one strategy incorporating AIE (tetraphenylethylene), chain transfer (hydroxyl), and co-catalytic (pyridinium salt) properties into one system is proposed to synthesize AIEgen end-labeled PPC as a thermometer material. Based on the twisted intramolecular charge transfer effect of the AIE unit, the fiber thermometer obtained by melt spinning transforms the invisible temperature gradient information into different fluorescent colors that are visible to the naked eye. In the range of −40 to 140 °C, multiscale temperature visualization applications, such as regional temperature detection, internal one-dimensional (1D) and two-dimensional (2D) temperature mapping, etc., could be implemented at a high resolution (±1 °C, 10 μm).