Construction of Self-Reporting Biodegradable CO2-Based Polycarbonates for the Visualization of Thermoresponsive Behavior with Aggregation-Induced Emission Technology

摘要

Thermoresponsive polymers with simultaneous biodegradability and signal "self-reporting" outputs that meet for advanced applica-tions are hard to obtain.To address this issue,we developed fluorescence signal "self-reporting" biodegradable thermoresponsive polycarbonates through the immortal copolymerization of CO2 and oligoethylene glycol monomethyl ether-functionalized epoxides in the presence of hydroxyl-modified tetraphenylethylene (TPE-OH).TPE-OH was used as chain transfer agent to afford well-defined polycarbonates with controlled molecular weight (6000-17000 g·mol-1) and aggregation-induced emission characteristics.Through temperature-dependent fluorescence intensity study,low critical solution transition of TPE-labeled polycarbonates were determined and the fine details of thermal-induced phase transition process were monitored.Further research indicated that temperature-con-trolled aggregation and dissociation of TPE moieties are the main reason for fluorescence intensity variations.We anticipate that this work could offer a method to visualize the thermal transition process of thermoresponsive polycarbonates and broaden their applica-tion fields as smart materials.