Abstract
The host–dopant approach is widely employed in OLED emissive layers. The local environment of the emitter strongly influences its photophysical properties and can either enhance or completely quench the emission . Although this phenomenon has been extensively investigated for small-molecule thermally activated delayed fluorescence (TADF) emitters, considerably less attention has been paid to TADF copolymers. In particular, the effect of copolymer composition remains largely unexplored, despite the substantial differences in the electronic properties of the comonomers, which may significantly alter the local environment of the emissive units and, consequently, their luminescence characteristics. In this work, the copolymerization kinetics of donor monomers based on N-phenylcarbazole and 3,6-di-tert-butyl-N-phenylcarbazole with the acceptor monomer 2,4,6-triphenyl-1,3,5-triazine were investigated (Fig. 1). Homopolymers and donor–acceptor copolymers with donor-to-acceptor (D:A) ratios of 50:50, 90:10, and 99:1 were synthesized and characterized by GPC, HPLC, 1H and 13C NMR spectroscopy, elemental analysis, TGA, DSC, and optical spectroscopy of dilute THF solutions.