Chain-stiffening enhanced ultralong organic phosphorescence in high glass transition temperature polymers

Polymer-based phosphorescent materials with excellent processability and thermal stability are essential for organic optoelectronic applications. However, developing high-performance polymer-based room-temperature phosphorescence materials remains a significant challenge due to extensive macromolecular chain mobility, which leads to exciton dissipation and phosphorescence quenching of chromophores. Herein, we present a straightforward strategy to stiffen the polymer chains to restrain chain mobility for achieving ultralong organic phosphorescent emission. As a result, these polymeric phosphorescent materials have a high glass transition temperature (T_g) of 165 °C and exhibit an ultralong-lived RTP emission lifetime of 3.89 seconds. The universality of the design principle was further verified by doping various chromophores into the rigid polymer matrix. Given the ultralong phosphorescence lifetimes of the materials, we demonstrated their potential application in information encryption. These findings provide a strategic guideline for designing ultralong-lived room temperature phosphorescent polymeric materials.