间位聚亚吡啶基亚乙炔基共轭聚电解质的合成与溶液光物理性质

合成了单体1,4-双(3-磺酰化丙氧基)-2,5-二碘苯与2,6-二乙炔基吡啶,利用Heck-Sonogashira偶联反应制备了间位聚亚吡啶基亚乙炔基共轭聚电解质m-PPYPE-SO3Na,对单体以及聚合物进行了红外光谱与核磁氢谱表征.测试了该共轭聚电解质m-PPYPE-SO3Na的紫外-可见吸收光谱与荧光发射光谱.研究了该共轭聚电解质的溶液光物理性质,发现该聚电解质具有荧光发射的溶剂依赖性以及浓度依赖性,在水溶液中存在聚集.在聚合物溶液浓度为1×10-6mol/L左右时,聚集发射基本消失,说明此时在溶液中聚合物的聚集程度已经比较低.该聚电解质在水溶液中与表面活性剂之间存在一定的相互作用,加入非离子型高分子表面活性剂聚乙烯吡咯烷酮(PVP)的聚合物水溶液荧光显著增强,表明该表面活性剂破坏聚电解质的聚集.该共轭聚电解质的溶液光物理性质表明其具有成为水溶性荧光探针的应用潜力.

SYNTHESIS AND SOLUTION PHOTOPHYSICS PROPERTIES OF A meta-LINKED ANIONIC POLY(PYRIDINYLENE ETHYNYLENE) CONJUGATED POLYELECTROLYTE

The monomer 1,4-diiodo-2,5-di(propyloxysulfonate)benzene and 2,6-diethynylpyridine were synthesized and a meta-linked anionic poly(pyridinylene ethynylene) conjugated polyelectrolyte m-PPYPE-SO3Na was synthesized via Pd-catalyzed Heck-Sonogashira coupling reaction.Monomers and the polymer were characterized by Fourier transformed infrared spectroscopy and proton nuclear magnetic resonance spectroscopy.The conjugated polyelectrolyte m-PPYPE-SO₃Na was characterized by UV-Vis and photoluminescence spectroscopy and the solution photophysics properties of the polymer were investigated.The fluorescence spectra of the conjugated polyelectrolyte in different solvent and under different polymer concentrations showed concentration- and solvent-dependency of the conjugated polyelectrolyte,respectively,which could be attributed to the aggregation of the conjugated polyelectrolyte in water solution.The emission peak of the aggregation disappeared approximately when the concentration of the polymer was about 1×10^-6 mol/L,and this fact shows that the extent of the polymer aggregation was very low.It was found that surfactant affected the aggregation of the polyelectrolyte.The introduction of polymer-type surfactant poly(vinyl pyrrolidone) (PVP) into the water solution of m-PPYPE-SO₃Na increased the fluorescence intensity of the polymer solution.The interaction of PVP with m-PPYPE-SO₃Na in aqueous solution broke the aggregation of the conjugated polyelectrolyte.The solution photophysics properties suggests that the conjugated polyelectrolyte has potential to be a kind of water soluble fluorescence probe.