【摘要】 以1,3-二(二苯膦基)丙烷二氯化镍(Ⅱ)作催化剂[Ni(dpp)Cl2],通过2,5-二溴噻吩格式试剂与4,4′-二碘偶氮苯共聚得到了一种新型共轭聚合物.采用红外光谱、核磁共振氢谱对聚合物的结构进行表征并通过紫外-可见吸收光谱、荧光光谱、X-射线衍射、热失重分析(TGA)、差热分析(DTA)等测试手段对聚合物的性能进行了详细的研究.紫外可见光谱分析结果表明,聚合物在384 nm处显示了偶氮苯发色团的特征吸收峰,相对于单体红移34 nm.在聚合物的氯仿溶液中观察到酸致变色现象,即分别加入CF3COOH和CH3SO3H后,溶液颜色由黄色分别变成墨绿色和紫色,而加入三乙胺溶液后溶液恢复到初始颜色.在25℃下测得的特性粘数为0.53 dL/g.热失重分析结果显示,该聚合物具有较好的热稳定性.更多还原

【Abstract】 A new type π-conjugated copolymer was obtained by the polymerization of 2,5-dibromothiophene Grignard reagents and 4,4′-diiodoazobenzene through nickel（II） complexes catalyzed cross-coupling reactions.Both monomers and polymer were characterized by（）¹H-NMR,FT-IR,UV-Vis and fluorescent spectroscopy,XRD and thermal analysis.The results from FT-IR and（）¹H-NMR showed that the copolymer had the structure as expected.The copolymer obtained by this method gives isolated yields of 80%.Intrinsic viscosity [η] of the polymer is about 0.53 dL/g in sulfuric acid at 25℃.The polymers are brown powders and have good solubility in common organic solvents such as dimethyl sulfoxide（DMSO）,dimethylformamide（DMF）,N-methyl-2-pyrrolidone（NMP）,CHCl₃ and slightly soluble in tetrahydrofuran（THF）,benzene,toluene etc.The UV-Vis spectra of the copolymer in CHCl₃ showed one broad absorption peak at 384 nm,and the PL spectrum gave a peak at 523 nm.This indicates that the polymers have good fluorescence.It was observed that the copolymer was quite sensitive to acids,and the acidichromatic behavior was investigated applying organic acids such as CF₃COOH and CH₃SO₃H.After adding acids,CF₃COOH and CH₃SO₃H,the color of the polymers chloroform solution changed from yellow to deep green or violet.Addition of triethylamine（Et₃N） in an equal amount to the acid leads to almost complete return of the original color immediately.XRD spectrum of the polymers revealed that the polymer had no obvious crystalline structure,however,showed somewhat orderly packed structure.The TGA results indicated that the polymer began to decompose above 326℃,having good heat stability.It is expected to be used as polymer materials with electro-optical properties.更多还原