含苯并硒二唑聚咔唑/芴类共轭聚电解质及其前驱体的合成与性能研究

采用Suzuki偶合反应合成了一系列新型的咔唑、芴和2,1,3-苯并硒二唑的共聚物——聚3,6-(N-(2-乙基己基))咔唑-2,1,3-苯并硒二唑-9,9-双(N,N-二甲基胺丙基)芴](PCzN-BSeD)及其相应的聚电解质衍生物——聚3,6-(N-(2-乙基己基))咔唑-2,1,3-苯并硒二唑-9,9-(双(3′-(N,N-二甲基)-N-乙基铵)丙基)芴]二溴(PCzNBr-BSeD).在聚咔唑和芴中引入不同比例的2,1,3-苯并硒二唑(BSeD)单元,引起了由咔唑和芴链段向窄带隙苯并硒二唑(BSeD)单元有效的能量转移.通过对聚合物电致发光性能的研究,发现用聚(3,4-亚乙基二氧基噻吩)(PEDOT)或聚(3,4-亚乙基二氧基噻吩)/聚乙烯咔唑(PEDOT/PVK)作为空穴传输层时,器件的性能相差不大,表明咔唑的引入较明显的改善了聚合物的空穴注入性能.而且几乎所有的聚合物用高功函数铝作阴极的器件和用钡/铝作阴极的器件具有相近的发光性能,表明这类聚合物具有良好的电子注入性能.

SYNTHESIS AND PROPERTIES OF POLYCARBAZOLE/FLUORENE-BASED CONJUGATED POLYELECTROLYTES WITH 2,1,3-BENZOSELENADIAZOLE AND THEIR PRECURSORS

A series of novel carbazole/aminoalkyl-substituted fluorene based main chain copolymers(poly3,6-(N-(2-ethylhexyl)carbazole)-(9,9-bis(3′-(N,N-dimethylamino)propyl)-2,7-fluorene)-4,7-(2,1,3-benzoselenadiazole)](PCzN-BSeD)) with different contents of 2,1,3-benzoselenadiazole(BSeD) were synthesized by Suzuki coupling reaction.Through a postpolymerization treatment on the terminal amino groups,corresponding quaternized ammonium polyelectrolyte derivatives(poly3,6-(N-(2-ethylhexyl)carbazole)-(9,9-bis(3′-((N,N-dimethyl)-N-ethylammonium)propyl)-2,7-fluorene)-4,7-(2,1,3-benzoselenadiazole)] dibromide(PCzNBr-BSeD)) were obtained.It was observed that the efficient energy transfer occured under optical and electrical excitation on the narrow band gap BSeD site for both the neutral and the quaternized copolymers.Devices with(poly(3,4-ethylenedioxythiophene)/poly(vinylcarbazole))(PEDOT/PVK) as an anode buffer,the external quantum efficiencies of the copolymer show similar devices performance to those by using poly(3,4-ethylenedioxythiophene)(PEDOT) only.It indicated that introduction of a carbazole segment into polymer main chains offered the enhanced hole-injection and transport properties.It was also found that devices from these polymers with a high work-function metal cathode such as Al showed similar devices performance to that by using the low work-function cathode such as Ba,indicating the excellent electron injection ability of these polymers.