| In recent decades, organic conducting polymers as a novel kind of polymers have caused many revolutionary changes in the field of polymers. Organic conducting polymers have high conductivity and electrochemical activity, which behave and exhibit properties similar to metals or semiconductors. The unique features enable them to be applied widely in new electronical devices, such as biosensors, organic light emitting diodes, and supercapacitors.Polyacetylene as the simplest conjugated polymers has a greatly improved electronic conductivity after doping, and accept much attention as an important sort of conducting polymers in the last decades. Regretfully, most of the researches about polyacetylene as conducting polymers mainly concentrated on some aspects including the mechanism of conducting, doping methods and mechanisms, the improvement of electronic conductivity, etc. There are few researches about the ionic conductivity of polyacetylene with functional substituents.In this dissertation, we designed and synthesized neutral and ionic 1,6-heptadiyne monomers with dendronized 1,2,3-triazole-octyl pendants and dendronized 1,2,3-triazole-OEG pendants, respectively. Then, we obtained netural and ionic poly(l,6-heptadiyne) derivatives with excellent thermal stability and electrochemical stability via MCP. After doping the neutral and ionic poly(1,6-heptadiyne) derivatives with iodine and lithium bis(trifluoromethanesulfony)imide (LiTFSI), we investigated the effect of polymer structures and doping concentration on the electronic/ionic conductivity.Firstly, we synthesized successfully neutral 1,6-heptadiyne monomers with dendronized 1,2,3-triazole-octyl pendants and dendronized 1,2,3-triazole-OEG pendants, respectively. Furthermore, the monomers carried out MCP with the Grubbs-type third generation Ru-based catalyst (Ru-Ⅲ), and obtained polyacetylene derivatives with high molecular weights and narrow PDIs. The results of NMR, UV-vis, and FT-IR indicated that the polymers had trans- and five-membered ring microstructures. We characterized the thermal properties of polymers with DSC and TGA, which indicated that the dendronized polymers possessed good thermal stability (Td>220 ℃). Meanwhile, the dendronized polymers exhibited good oxidation stability. Afterwards, the ionic conductivity of polymers doped with LiTFSI was studied by the Electrochemical Impedence Spectroscopy, and the highest ionic conductivity obtained was 4.3 × 10-6 S·cm-1. The electrochemical stability window of polymers at room temperature was characterized by Linear sweep voltammetry, and it varied from 5.9 to 6.0 V, which demonstated the excellent electrochemical stability.Secondly, we synthesized ionic 1,6-heptadiyne monomers from their corresponding neutral 1,6-heptadiyne monomers. Then, the ionic monomers carried out MCP with the catalyst Ru-Ⅲ, which yielded ionic dendronized polyacetylene derivatives with trans-and five-membered ring microstructures. The ionic polymers had relatively low molecular weights, but showed lower glass-transition temperature (Tg<-10 ℃), higher thermal decomposition temperature(Td>320 ℃), and better thermal stability. After that, the results of Electrochemical Impedence Spectroscopy indicated that the ionic conductivity of ionic polymers at room temperature were preferable than their corresponding neutral polymers. The highest ionic conductivity of undoped, LiTFSI doped and I2 doped ionic polymers were 7.3×10-5 S·cm-1,1.4 × 10-4 S·cm-1, and 4.2 × 10-4 S·cm-1, respectively. In addition, the electronic conductivity of ionic polymer with 1,2,3-triazolium-OEG pendants was improved greatly to 4.1 × 10-5 S·cm-1. The ionic polymers exhibited wide electrochemical stability window (5.8-6.1 V) and excellent electrochemical stability. |
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