含吩噻嗪及其衍生物的聚合物有机电致发光材料的合成和器件制备

利用吩噻嗪单体的空穴传输能力、吩噻嗪衍生物单体的拉电子特性和它们分子结构的非共面性,制备了高效的含吩噻嗪及其衍生物结构单元的对苯撑乙烯聚合物有机电致发光材料P1。同时在单体中引入了烷氧基和长链烷基,使得合成的聚合物在四氢呋喃、氯仿、二氯甲烷、甲苯等溶剂中有较好的溶解性。研究吩噻嗪衍生物单体的拉电子特性对聚合物P1的电子传输性能的影响,合成不含吩噻嗪衍生物的同一类型聚合物P2。制备以聚合物P1和P2为发光层的单层OLED器件,经测量,聚合物P1的器件外量子效率是聚合物P2器件的3.5倍。

Synthesis and Electroluminescent Property of Polymers Based on Phenothiazine and Phenothiazine-5-oxide

It has been demonstrated that phenothiazine unit (M2) is a excellent p-type building block for lowering IP (ionic potential) of conjugated polymers due to its readily injection and transport of hole.Unlike phenothiazine,phenothiazine-5-oxide (M3) is a specific molecular which may be a good electron transporting unit due to the conversion of electron-donating sulfur atom to electron-withdrawing sulfoxide group.M3 was synthesized successfully through five-step reaction including: (1) nucleophilic substitution alkylation of initial material phenothiazine, (2) Vilsmeier reaction of the above product, (3) protection of aldehyde group, (4) oxidation of sulfur to sulfoxide and (5) hydrolysis of acetal.Using the hole transport property of M2 and the electron transport property of M3,we synthesize a high efficient electroluminescent polymerP1],meantime the two units have the nonplanarity charateristic of molecular structures which can impede π-stacking aggregation and intermolecular excimer formation to improve the quantum efficience of P1.Aflexible long chain is fused on the phenothiazine ring to improve the solubility of polymer in furan,chloroform,toluene.To investigate the effect of electron-withdrawing of phenothiazine-5-oxide on the electron transport characteristic,polymer (P2) which doesn’t contain phenothiazine-5-oxide unit is synthesized with the same method as P1.For comparison,P1 and P2 are fabricated into single layer devices,and the external quantum efficiency of P1 device is 2.5 times more than that of P2 device.It implies that the introduction of M3 effectly improve the luminescent efficiency of P1.