2种苯并咪唑衍生交替共聚物的合成及性能

Synthesis and Characterization of Benzimidazole Alternating Copolymers with Dioctyloxy-Diethynyl-Phenylene and Dioctyl-Fluorene

以苯并噻二唑作为初始原料,通过Sonogashira、Suzuki反应将4,7-二溴-2-己基-1,3-苯并咪唑单体分别与带有不同烷氧基链的对苯乙炔、9,9-二辛基芴进行交替共聚,得到了聚[2-己基-1,3-苯并咪唑-1,4-二乙炔基-2,5-二辛氧基苯](P1)、聚[2-己基-1,3-苯并咪唑-1,4-二乙炔基-2,5-二(十二烷氧基)苯](P2)和聚[2-己基-1,3-苯并咪唑-9,9-二辛基芴](P3)。采用红外光谱、核磁共振等手段对单体和共聚物的结构进行了表征,利用紫外-可见吸收光谱、荧光量子效率测试和循环伏安法对聚合物的光、电化学性能进行了探讨。结果表明,共聚物P1、P2均在445 nm处出现紫外-可见吸收峰,共聚物P3在376 nm处出现紫外-可见吸收峰。P2、P3共聚物的相对荧光量子效率分别为80%,66.7%,所得共聚物都有较强的荧光性能。P2共聚物在1.3 V处出现氧化掺杂峰,在-1.3 V处出现还原掺杂峰,P3共聚物在0.48 V处出现氧化掺杂峰,0.34 V处出现脱掺杂峰。

The monomer 2-decoyl-4,7-dibromo benzimidazoles was synthesized using benzo-thiadiazole as initial material. Its alternating copolymers of poly(2,5-dioctyloxy-1,4- diethynyl-phenylene-alt-2-decoyl-1,3-benzimidazole)(P1),poly(2,5-didodecyloxy-1,4-diethynyl-phenylene-alt-2-decoyl-1,3-benzimidazole)(P2) and poly(9,9-dioctylfluorene-alt-2-decoyl-1,3-benzimidazole)(P3) were prepared with 2,5-didodecyloxy-1,4- diethynlbenzene and 9,9-dioctyl-fluorene by Sonogashira and Suzuki reaction. Both monomers and copolymers were characterized by FT-IR,1HNMR. UV-Vis,fluorescence quantum yield and cyclic voltammetry were investigated. UV-vis results of the copolymers P1 and P2 show the maximum absorption peak at 445 nm,the maximum absorption of the copolymer P3 appeares at 376 nm. The copolymers of P2 and P3 give the fluorescence quantum yield of 80% and 66. 7% respectively. Copolymers have strong fluorescence properties. The copolymer of P2 has the maximum oxidation peak at 1. 3 V and maximum reduction peak at- 1. 3 V. The copolymer of P3 has the maximum oxidation peak at 0. 48 V and the maximum undoped reduction peak appears at 0. 34 V.