Rehealable and Recyclable Aggregation-Induced Emission (AIE)-Active Luminescent Vitrimers

Incorporating an aggregation-induced emission (AIE) effect into polymers will lead to intriguing solid-state fluorescent materials (i.e., AIE-active polymers) that have great potential in optoelectronics and sensing applications. In this work, a series of AIE-active polyimine vitrimers (TPE-PIs), containing different loadings of tetraphenylethene (TPE) moieties, have been successfully prepared where AIE-active monomers are chemically integrated into the PI network, either as side chains or in the backbone of the polymer network. The studies reveal that TPE-PIs not only inherit the merits of PI vitrimer (i.e., rehealability, malleability, recyclability) but also provide enhanced mechanical (compared to thermoplastic AIE-active polymers) and luminescent properties (compared to pristine AIE-inactive PIs). Larger enhancement could be achieved when TPE moieties are installed in the polymer backbones, in comparison to those installed in the side chains. Furthermore, their photoluminescence intensity could be significantly enhanced in an underwater environment, exhibiting great potential in underwater applications for luminescent sensing and/or light-emitting.