含有偶氮苯和1,3,4-噁二唑结构聚合物的合成及性能

Synthesis and Properties of Polymer Containing 1,3,4-Oxadiazole and Azobenzene Units

合成了同时含有偶氮苯和1,3,4-噁二唑结构的新型共轭聚合物(LPOXD),采用FT-IR、UV-Vis、1HNMR、GPC、TGA和DSC测试技术对其结构进行了表征。结果表明,所得共轭聚合物的特性粘数为0.02960L/g,Mw和分子量分布指数PDI分别为8500g/mol和1.55。质量损失5%的温度为290℃,Tg为92.8℃。长烷氧基侧链的引入极大地提高了LPOXD在氯仿和四氢呋喃等有机溶剂中的溶解性。采用紫外-可见吸收光谱、荧光光谱及循环伏安对LPOXD的光电性能进行了研究。结果表明,在365nm紫外光照射下,LPOXD中偶氮苯发生反-顺异构化;350nm光激发下,LPOXD在蓝紫光波长范围内发射荧光;循环伏安测试得出LPOXD最高占有轨道(HOMO)能量和最低空轨道(LUMO)能量分别为-5.96和-3.17eV。

A novel conjugated polymer containing azobenzene and 1,3,4-oxadiazole units（LPOXD） was synthesized.The structure of the LPOXD was charactered by FT-IR,UV-Vis,1H NMR,GPC,TGA and DSC.The results indicate that the intrinsic viscosity of the LPOXD is 0.02960 L/g,and its Mw and molecular mass distribution or polydispersity index（PDI） values are 8500 g/mol and 1.55,respectively.A 5% mass loss of the LPOXD occurred at 290 ℃.The glass-transition temperature（Tg） is 92.8 ℃.The introduction of long side chain of alkoxy significantly improved LPOXD＇ s solubility in common organic solvents such as chloroform,tetrahydrofuran,and so on.Furthermore,the optical and electrochemical properties of the LPOXD were investigated throughly by UV-Vis absorption spectroscopy,fluorescence emission spectroscopy and cyclic voltammetry.The results indicate that the azobenzene in the LPOXD involve a trans-cis photoisomerization under the radiation of 365 nm UV light.A wide fluorescence peak of the LPOXD appeared in the wavelength range of blue and purple light under excitaion at 350 nm.Cyclic voltammetry reveals that the LUMO and HOMO energies of the LPOXD are-5.96 eV and-3.17 eV,respectively.