通过钯催化的Heck耦合反应,合成了一种含噁二唑基团与MEHPV单元的交替共聚物(oxa-MEHPV),并利用UV-vis,FT-IR,^1H-NMR对其单体和聚合物的结构进行了表征,研究了目标聚合物的荧光性能、由于在MEH-PPV的主链骨架上引入噁二唑基团,oxa-MEHPV分子链的刚性得到增强,表现出更好的热稳定性能,在常规有机溶液如氯仿、二氯甲烷、甲苯等中也有更好的溶解性.同时,由于噁二唑具有很好的电子亲和能力,聚合物紫外吸收波长发生了较大的蓝移,较MEH-PPV拥有了更好的电子迁移率和更高的荧光量子效率,因而在聚合物电致发光(PLED)领域有潜在的应用前景.
A poly ( p-phenylenevinylene ) ( PPV ) alternating copolymer, poly [ ( 2, 5-diphenylene-1, 3, 4-oxadiazole )-4-4' - vinylene-alt-2-methoxy-5-( 2-ethylhexyloxy )-1, 4-phenylenevinylene] (oxa-MEHPV), is synthesized by Heck coupling reaction and characterized with UV-vis, Fourier transform infrared ( FT-IR ), ^1H-NMR and photoluminescence ( PL ) spectroscopy, oxa-MEHPV possesses an outstanding thermal stability and shows excellent solubility in common organic solvents such as dichloromethane, chloroform, toluene, and tetrahydrofuran(THF). The introduction of the electron-deficient 1, 3, 4-oxadiazole units into the MEH-PPV backbone also increases the electron affinities of the conjugated segment, which leads to the blue-shift of the maximum absorption wavelength and makes the polymer have a high optical band-gap energy, good electron-transporting stability and high PL quantum yield.