In situ monitoring of photo-PISA via aggregation-induced emission (AIE) technology

Aggregation-induced emission (AIE) has already been applied for in-situ monitoring living radical polymerization process. Here we utilized functionalized monomer TPEE as fluoresce probes for the in-situ monitoring of photo-induced RAFT-PISA process. Hydrophilic POEGA macro chain transfer agent (Macro-CTA) was first prepared with light sensitive CTA 4-Cyanopentanoic acid dithiobenzoate, and (2-(4-vinylphenyl)ethene-1,1,2-triyl)tribenzene (TPEE) was copolymerized with styrene to form the hydrophobic block under UV irradiation. The growth of hydrophobic block induced the self-assembly of polymer chains and the emission signal could be observed by naked eyes afterwards. The PL intensity increased with the increase of particle size, as well as the monomer conversion and molecular weight, owing to the enhancement of AIE monomer in the self-assembly latex particles. This no-invasive and facile approach to in-situ visualization and continuously monitoring of the photo-induced RAFT-PISA process might be helpful for both scientific research and commercial application.