Branched 1,2,3-Triazolium-Functionalized Polyacetylene with Enhanced Conductivity

Abstract

Metathesis cyclopolymerization of mono- or bissubstituted 1,6-heptadiynes is undergone to generate the ionic polyacetylenes (iPAs) with branched 1,2,3-ttriazolium pendants, which possess relatively high intrinsic ionic conductivities of 1.4 × 10 -2.1 × 10 S cm at 30 °C. The doping treatment with lithium bis(trifluoromethanesulfonyl)imide endows iPAs with enhanced ionic conductivities of 2.5 × 10 -4.3 × 10 S cm . Further doping with iodine, iPAs show ionic and electronic dual conductivities of 4.5 × 10 -7.1 × 10 and 1.5 × 10 -4.5 × 10 S cm , respectively. Therefore, the doped iPAs demonstrate the potential in the area of conducting polymers and polymeric electronics.

Enhanced Ionic and Electronic Conductivity of Polyacetylene with Dendritic 1,2,3‐Triazolium‐Oligo(ethylene glycol) Pendants

“…The intrinsic σ i of P ( 1 ‐ co ‐ 3 ) was similar with that of P2 , and thus no further study was given in the following section. The σ i of these iPAs was three orders of magnitude higher than that of neutral PAs with dendronized 1,2,3‐triazole (5.3 × 10 −8 S cm −1 ), higher than those of hyperbranched poly(1,2,3‐triazolium) (7.7 × 10 −6 S cm −1 ) and iPAs with disubstituents of branched 1,2,3‐triazolium (1.9 × 10 −5 S cm −1 ), and even better than that of 1,2,3‐triazolium‐based poly(ionic liquid)s (1.6 × 10 −5 S cm −1 ), likely due to the contribution of high ion density and low T g from the dendronized 1,2,3‐triazolium structure and the flexible OEG groups; of course, poly(siloxane ionic liquid) with 1,2,3‐triazolium‐OEG pendants displayed a slightly higher σ i of 7 × 10 −5 S cm −1 , because of its highly flexible polysiloxane backbone with very low T g of −62 °C.…”

“…Chemical doping is an effective approach to enhance the σ e of PAs. Shirakawa and co‐workers found that the PA film showed a dramatic increase in σ e when doped with controlled amounts of halogens, and particularly, I 2 contributes significantly to increase the σ e of PA. Our group reported that the σ e of I 2 ‐doped PAs reached up to 4.5 × 10 −6 S cm −1 by immersing the as‐prepared polymer film into the saturated I 2 solution of CCl 4 . This method may just change the electrical conducting properties of the polymers on the surface, and the bulk characteristics of polymer doped with I 2 was not revealed.…”

“…Poly(ionic liquid)s (PILs) are peculiar polyelectrolytes combining the unique properties of ionic liquids (e.g., thermal stability, versatile anion exchange, and chemical stability) with polymer materials (e.g., mechanical, stability, processability, durability, and tunable architecture from macromolecular design) . Compared with neutral polymers, PILs usually have higher ionic conductivity (σ i ). In recent years, PILs were extensively studied basing on various cations (e.g., phosphonium, pyrrolidinium, imidazolium, and 1,2,4‐triazolium) and anions (e.g., halides, triflate, and tosylate).…”

“…Buchmeiser and co‐workers reported that PAs with five‐membered rings by MCP, which was doped by I 2 and NO + BF 4 − , and achieved high conductivity. Recently, MCP was also proved to fit well to the ionic 1,6‐heptadiyne derivatives, generating ionic PAs (iPAs) . On the basis of our previous work, we combined the dendritic 1,2,3‐triazolium moiety with oligo(ethylene glycol) (OEG) group, instead of the ill‐defined branched 1,2,3‐triazolium or dendronized neutral 1,2,3‐triazole and alkyl group, as the pendant of the PA backbone to synthesize the dendronized trans ‐iPAs with well‐defined ionic density and five‐membered ring microstructure via MCP, and the iPA solution was doped with the solution of bis(trifluoromethane)sulfonimide lithium (LiTFSI) and I 2 at different molar ratios of dopant to polymer, which is different from the previous doping procedure of immerging the polymer film in dopant solution, affording a fully mixed and soluble doped‐iPA solution, and aiming to gain the iPAs with improved ionic and electronic dual conductive performance.…”

Unexpectedly Facile Rh(I) Catalyzed Polymerization of Ethynylbenzaldehyde Type Monomers: Synthesis of Polyacetylenes Bearing Reactive and Easy Transformable Pendant Carbaldehyde Groups

“…Pendant functional groups of polyacetylenes may serve as a tool for introducing or tuning the properties of these polymers, e.g., the conductivity, photoconductivity, specific interaction with molecules or ions, luminescence, helical conformation, and side‐chain liquid crystalline character . Reactive pendant functional groups of polyacetylenes can be moreover chemically modified using various postpolymerization reactions under formation of linear or cross‐linked polymers of modified qualities.…”