Despite the steady progress of TADF polymer research, the inter/intra-molecular interaction between TADF units is still a big factor to induce the detrimental extinction of excited excitons. Herein, a new strategy, named side-chain encapsulation and main-chain blocking (SEMB), was proposed to construct TADF polymers with minimized inter/intra-molecular interaction of TADF units. The bulky carbazole and biphenyl fluorene are deftly introduced as encapsulation and blocking units by flexible hexane chains at the periphery of the Triazin-carbazole luminance cores. Both photophysical and electro-luminance results of the four TADF polymers varied in steps along their molecular structure and interaction, which proves the effectiveness of the SEMB strategy in the macro-molecular system. Indeed, the deep-blue device based on SEMB polymer P-CzTCFu achieved a maximum external quantum efficiency (EQE) of 22.1%, which was 3 times outperforming the reference polymer without any protection. Further using such a TADF polymer as a sensitizer for hybrid white OLEDs lead to an optimized high EQE of 26.7%, which was among the highest value in previously reported solution-processed hybrid white OLEDs. We also successfully prepared the first TADF polymer-based flexible OLEDs with good bending resistance. This work reveals the potential and importance of SEMB strategy for opening a new route for TADF polymer design toward highly efficient solution-processed OLEDs.

中文翻译：

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具有优化分子结构和相互作用的高效 TADF 聚合物，用于构建 EQE 高于 26% 的溶液加工混合白色 OLED

尽管TADF聚合物研究取得了稳步进展，但TADF单元之间的分子间/分子内相互作用仍然是引起激发激子有害消光的一个重要因素。在此，提出了一种称为侧链封装和主链封闭（SEMB）的新策略来构建具有最小化TADF单元分子间/内相互作用的TADF聚合物。大体积的咔唑和联苯芴通过柔性己烷链巧妙地引入三嗪-咔唑发光核的外围作为封装和封闭单元。四种TADF聚合物的光物理和电致发光结果随着其分子结构和相互作用的变化而逐步变化，这证明了SEMB策略在大分子系统中的有效性。事实上，基于SEMB聚合物P-CzTCFu的深蓝色器件实现了22.1%的最大外量子效率（EQE），是没有任何保护的参考聚合物的3倍。进一步使用这种 TADF 聚合物作为混合白色 OLED 的敏化剂，可实现 26.7% 的优化高 EQE，这是之前报道的溶液加工混合白色 OLED 中的最高值之​​一。我们还成功制备了第一个基于TADF聚合物的柔性OLED，具有良好的抗弯曲性。这项工作揭示了 SEMB 策略的潜力和重要性，为 TADF 聚合物设计通往高效溶液加工 OLED 开辟了一条新途径。