Chinese Journal of Organic Chemistry ›› 2020, Vol. 40 ›› Issue (3): 763-773.DOI: 10.6023/cjoc201905030 Previous Articles     Next Articles


姜鸿基, 何煦, 李雄   

  1. 南京邮电大学信息材料与纳米技术研究院 有机电子与信息显示国家重点实验室培育基地 江苏省有机电子与信息显示协同创新中心 南京 210023
  • 收稿日期:2019-05-14 修回日期:2019-08-16 发布日期:2020-04-02
  • 通讯作者: 姜鸿基
  • 基金资助:

Synthesis and Characterization of Blue Light Emitting Polymer Based on 2,4,6-Triphenyl-1,3,5-triazine and 1-(4-Hexyloxy)-benzene Functionalized Fluorene Units

Jiang Hongji, He Xu, Li Xiong   

  1. Nanjing University of Posts and Telecommunications, Institute of Advanced Materials, Key Laboratory for Organic Electronics and Information Displays and Jiangsu Key Laboratory for Biosensors, Jiangsu National Synergetic Innovation Center for Advanced Materials, Nanjing 210023
  • Received:2019-05-14 Revised:2019-08-16 Published:2020-04-02
  • Supported by:
    Project supported by the National Natural Science Foundation of China (No. 21574068), the Major Research Program from the State Ministry of Science and Technology (No. 2012CB933301) and the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD, YX030003).

Polymer 3 based on 1-(4-hexyloxy)-benzene and 2,4,6-triphenyl-1,3,5-triazine functionalized fluorene units was synthesized and characterized, whose optoelectronic properties were further compared with those of poly(9,9-dihexyl-fluorene) (1) and poly(9,9-di(1-(4-hexyloxy)-phenyl)-fluorene) (2). The 5% weight loss temperatures of polymers 1, 2 and 3 thin solid powders are 274, 318 and 401℃, and their glass transition temperatures in the same state are 91, 120 and 139℃, respectively. The maximum absorption and photoluminescent emission peaks of polymers 1, 2 and 3 in toluene solution are 380 and 435 nm, and their optical band gaps in toluene solution are 2.95, 2.95 and 2.91 eV. The triplet energy levels of polymers 1, 2 and 3 are 2.82, 2.81 and 2.97 eV, while their singlet energy levels are 3.14, 3.13 and 3.12 eV, which makes the singlet-triplet energy splitting gaps for polymers 1, 2 and 3 to be 0.32, 0.32 and 0.15 eV. The highest occupied molecular orbital energy levels of polymers 1, 2 and 3 are -5.72, -5.95 and -5.96 eV and the lowest unoccupied molecular orbital energy levels are -2.70, -2.39 and -2.34 eV. The introduction of 4-hexoxybenzene widened the energy band gaps of the polymers, while the electron deficient 2,4,6-triphenyl-1,3,5-triazine made the single-triplet energy splitting gaps of the polymers successively decreased, but it did not endow polymer 3 with thermally activated delayed fluorescence characteristic. With the introduction of rigid and electron deficient 2,4,6-triphenyl-1,3,5-triazine into the 9-carbon of the fluorene units in the polymer, the thermal stability, color purity and photostability of blue light emitting solid were improved in the turn of polymers 1, 2 and 3, which were further validated by the stable electroluminescent spectra of polymer 3. The wide-angle X-ray diffraction results of the polymers 1, 2 and 3 powders show that all polymers have excellent amorphous properties in nature. The phase diversity of polymer 3 powder locates between those of polymers 1 and 2, and the alkoxyl phenyl substituted group on the polymer 2 side chain is helpful to improve the diversity of ordered morphology in solid powder. The random copolymer 3 exhibits much better photoelectric properties than those of polymers 1 and 2.

Key words: polyfluorene, blue light, pendant group, 2,4,6-triphenyl-1,3,5-triazine, photo physics, thermal stability