LAUSR

Conjugated polymers are promising semiconducting materials for applications in organic electronic devices such as organic light‐emitting diodes (OLEDs). Recent advances in direct arylation polycondensation have enabled the synthesis of defect‐free polymers in the main chain; however, terminal groups have not been fully investigated. This research focuses on the synthesis of polymers with controlled terminal groups and the evaluation of their effects on photophysical and OLED properties. Investigation of the monomer feed ratio and terminal treatment methods allows the synthesis of three polymers with different terminal groups. The terminal groups affect the photoluminescence quantum yield in the thin‐film state and the external quantum efficiency in OLEDs. These findings indicate that a small percentage of terminal groups in the polymer material has a significant impact on the device properties.