Aggregation Induced Emission in Stereospecific, Photoluminescent Polymers

Aggregation induced emission (AIE) is a rare phenomenon where fluorophores emit light when closely packed together in concentrated solutions or aggregated solid states. As fluorescent properties of AIE fluorophores are highly influenced by their local environment, these dyes act as a unique tool to visualize nanoscale structures such as DNA and proteins. In particular, AIE is used to probe the dynamic helical conformation of these molecules with emission turning “on/off” depending on helix formation.In this work, we sought to explore AIE in stereospecific polymers that are known to form helices and study how changes in chain conformation can influence their fluorescent properties. Our attention was focused on stereospecific tetraphenylethylene (TPE) based polymers made up of bulky AIE pendent fluorophores and flexible methacrylate backbones. To make these polymers, the aggregation induced emission monomer TPE ethyl methacrylate (TPE-EtMA) was synthesized via air-free techniques. The polymerization of TPE-EtMA via anionic and radical polymerization was investigated to prepare stereospecific polymers and their stereo-irregular analogs. Future work will explore the stereochemistry-dependent fluorescent properties of these materials, and the ability to switch AIEactivity on/off through external stimuli. We predict that the results from this study will provide valuable insight into the structural design of AIE polymers and their luminescence-based applications.