Fluorescence Self‐Reporting Precipitation Polymerization Based on Aggregation‐Induced Emission for Constructing Optical Nanoagents

Abstract Precipitation polymerization is becoming increasingly popular in energy, environment and biomedicine. However, its proficient utilization highly relies on the mechanistic understanding of polymerization process. Now, a fluorescence self‐reporting method based on aggregation‐induced emission (AIE) is used to shed light on the mechanism of precipitation polymerization. The nucleation and growth processes during the copolymerization of a vinyl‐modified AIEgen, styrene, and maleic anhydride can be sensitively monitored in real time. The phase‐separation and dynamic hardening processes can be clearly discerned by tracking fluorescence changes. Moreover, polymeric fluorescent particles (PFPs) with uniform and tunable sizes can be obtained in a self‐stabilized manner. These PFPs exhibit biolabeling and photosensitizing abilities and are used as superior optical nanoagents for photo‐controllable immunotherapy, indicative of their great potential in biomedical applications.