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

The ionic polyacetylenes (iPAs) with dendritic 1,2,3-triazolium-containing oligo(ethylene glycol) (OEG) pendants are prepared by metathesis cyclopolymerization. The dendritic triazolium and flexible OEG pendants endow the iPAs with low glass transition temperature of −29.0 °C and enhanced intrinsic ionic conductivity (σ_i) of 5.0 × 10⁻⁵ S cm⁻¹ at 30 °C under anhydrous conditions. After solution doping with bis(trifluoromethane)sulfonimide lithium (LiTFSI), the σ_i of iPAs reaches up to 5.2 × 10⁻⁴ S cm⁻¹. When doped with iodine (I₂), the iPAs exhibit high electronic conductivity (σ_e) of 1.3 × 10⁻⁵ S cm⁻¹. If doped with both LiTFSI and I₂, the iPAs demonstrate the best dual σ_i and σ_e of 8.3 × 10⁻⁴ and 1.2 × 10⁻⁵ S cm⁻¹, respectively. Therefore, the dendritic triazolium-OEG pendants-functionalized iPAs display an improved conductive performance compared with the corresponding iPAs bearing dendritic triazolium-alkyl pendants, or branched triazolium-OEG pendants, before and after doping with different dopants, and will have the potential applications in electronics as the dual conductive materials.