Novel fluorene-based blue-light-emitting copolymers (F8Rs) in the β-phase are designed and synthesized using the palladium-catalyzed Suzuki reaction. The β-phase can be generated by introducing an ambipolar unit, that contains 10-n-hexylphenothiazine (PTZ) and 4-(dicyanomethylene)-2-methyl-6-[p-(dimethylamino)styryl]-4H-pyran (DCM) (as the donor and acceptor moieties, respectively) on a polyfluorene backbone. By comparing the absorption (peak at 437 ± 1 nm), photoluminescence (PL) (peak at 441 ± 1 nm), and X-ray diffraction (XRD) (peak centered around 2θ = 7.0°) characteristics of the resulting polymers (F8Rs) with those of the polyfluorene homopolymer (PFO), we found that fluorene-based copolymers with ambipolar moieties, such as PTZ and DCM, can prompt the formation of the β-phase after spin-coating without gelling in a poor solvent, exposure to tetrahydrofuran vapor, cooling to liquid-N2 temperature, and reheating. The PL and electroluminescence (EL) efficiencies of the copolymer F8R5 are higher than those of PFO (by factors of two and 15, respectively). The EL spectrum of the copolymer showed almost pure blue emission, with CIE (Commission Internationale de lâ²Eclairage) coordinates of x = 0.17 and y = 0.10.
利用
钯催化的铃木反应设计并合成了δ相的新型
芴基蓝光发光共聚物(F8R)。通过在聚
芴骨架上引入一个包含 10-正己基
吩噻嗪(
PTZ)和 4-(二
氰基亚甲基)-2-甲基-6-[对(二甲基
氨基)
苯乙烯基]-
4H-吡喃(DCM)(分别作为供体和受体分子)的双极单元,可以生成δ相。通过比较所得化合物的吸收(峰值在 437 ± 1 nm 处)、光致发光(PL)(峰值在 441 ± 1 nm 处)和 X 射线衍射(XRD)(峰值集中在 2θ = 7.通过对所得聚合物(F8Rs)的特性与聚
芴均聚物(PFO)的特性进行比较,我们发现,含伏极性分子(如
PTZ 和 DCM)的
芴基共聚物在旋转涂层后可促使δ相的形成,而无需在劣质溶剂中胶凝、暴露于
四氢呋喃蒸气中、冷却至液态-N2 温度并重新加热。共聚物 F8R5 的聚光和电致发光(EL)效率高于 PFO(分别高出 2 倍和 15 倍)。共聚物的电致发光光谱显示出几乎纯粹的蓝色发射,CIE(国际照明委员会)坐标为 x = 0.17 和 y = 0.10。