A radical polymer with efficient deep-red luminescence in the condensed state

Stable organic luminescent radicals with an open-shell character have attracted much attention recently due to their unique luminescent properties. However, to date, there has been no report on luminescent organic radical polymers. Herein, the first example of a luminescent radical polymer (PS–CzTTM), which consists of a polystyrene (PS) backbone decorated with randomly distributed pendants of luminescent radicals (CzTTM), is designed and synthesized. PS–CzTTM not only exhibits paramagnetic and good thermal properties, but also exhibits bright deep-red emission under UV light irradiation in the solid state. PS–CzTTM has high luminescence quantum yields both in solution (ϕ = 37.6%) and in the film state (ϕ = 24.4%) at room temperature. In addition, the photostability of PS–CzTTM is up to 300 times higher than that of the tris(2,4,6-trichlorophenyl)methyl radical.