One-pot preparation of nonconventional luminescent polymer gels driven by polymerization†

Nonconventional chromophores are good candidates for preparing luminous gels because their luminescence is usually enhanced in the aggregated state. In this work, a simple one-pot strategy for polymerization-induced gelation of polymer fluorescent gels was developed, and a self physically crosslinked luminous gel PUHG based on a non-conjugated/nonconventional luminous polyurethane derivative was obtained. Detailed experimental and theoretical studies probed the physical properties and luminescence principles of PUHG's aggregated state. Molecular dynamics simulations suggest that abundant non-covalent interactions and physical entanglement between polyurethane chains are the main driving forces of gel formation and the source of luminescence. PUHG displays stable photophysical properties, environmental tolerance, good adhesion properties and processability, leading to the validation of patterning applications of PUHG on different organic/inorganic substrates. This work broadens the application range of nonconventional luminous polymers and provides a simple route for large-scale preparation of fluorescent gel soft materials.