Facile preparation and properties of multifunctional polyacetylene via highly efficient click chemistry

A series of novel multifunctional polyacetylenes bearing oxadiazole and azo groups as molecular pendants were designed and synthesized via highly effective click chemistry. The resultant polymers showed good solubility in common organic solvents. The structure and properties of the resulting polymer were characterized and evaluated by FT-IR, H-1-NMR, UV-vis, TGA and FL analyses. The results show that the thermal stability of the synthesized functional polyacetylene was significantly increased when compared to single polyacetylene due to the jacket effect between the functional groups and backbone. The influence mechanism of the oxadiazole and azo groups was also discussed in detail. Simultaneously, the optical properties of the functional polyacetylene were investigated. It was found that the optical properties of the resulting polyacetylene were affected by the oxadiazole and azo groups. For P5-P7, the intensity of the absorption peak at ca. 452 nm, belonging to the azo group, decreased gradually as the content of M1 was reduced. In contrast, the intensity of the absorption peak at ca. 312 nm, belonging to the oxadiazole group, increased as the content of M2 increased. Due to azo group isomerization under the photothermal conditions, quenching of the fluorescence occurred in the range of molecules for M1, P2 and P3.