Syntheses And Properties Of Hyperbranched Polytriazole And Branched Triazole-Functionalized Polyacetylenes

Conductive polymers have been widely concerned by lots of researchers, and the rapid progress has been made in the field. In this thesis, the research was based on the advantage of triazole, triazolium, and polyacetylene (PA). Firstly, the branched triazole with low molecular weight (Mn) was synthesized via click chemistry, to act as the pendants of PA and generate the mixed ionic and electronic conductive polymer with electronic conductive PA main chain, as well as ionic conductive pendants. Simultaneously, the hyperbranched poly(triazole)s with high molecular weight were obtained. Hence, this thesis focused on the synthesis and properties of hyperbranched poly(triazole)s and poly(triazolium)s, as well as the PA with branched triazole and triazolium pendants, as depicted in the follows:Hyperbranched poly(triazole) (hb-PTA-OEG) with relative high molecular weight, narrow polydispersity index (PDI), as well as high degree of branch (DB= 0.59) was synthesized via click chemistry, the polymer displayed the thermal and metal ion dual stimuli-responsiveness. Among the metal ions, the addition of the Ag+ even at low concentration could significant altered the cloud point temperature of polymer due to the strong coordination between polymer and Ag+ion. In consequence, it provides a novel example for the selective absorption and separation of Ag+ ion by altering the temperature.Due to the strong coordinate with Ag+ ion, the hb-PTA-OEG/silver nanlparticles (NP) hybrid material with the size of 20 nm was thus generated via the reduction of AgNO3 in situ by using hb-PTA-OEG as stabilizer. The conductivity of hb-FTA-OEG/Ag NPs was first investigated, by comparison, the hb-PTA-OEG was also doped with AgNO3 and LiTFSI, respectively. Among them, the hb-PTA-OEG/Ag NPs was brittle solid and showed the highest conductivity of 2.6 × 10-5 S/cm at 30 ℃; the LiTFSI doped material showed lower conductivity of 1.3 × 10-6 S/cm at, as well as the viscous propertity; the AgNO3 doped material showed the comparable conductivity of 1.2 × 10-6 S/cm with the LiTFSI doped material, besides, the materials showed well film-forming ability, due to its coordination ability with Ag+ ion.To overcome the deficiency of low conductivity of the doped hb-PTA-OEG, hyperbranched poly(triazolium)s [hb-PTA]+[TFSI]-, [hb-PTA-Octyl]+[TFSI]-, [hb-PTA-TEG]+[TFSI]- and [hb-PTA-OEG]+[TFSI]- with different terminal groups were synthesized. Among them, [hb-PTA-OEG]+[TFSI]- presented the highest ionic conductivity of 7.7×10-6 S/cm-1 at 30℃, as well as a high electrochemical stability (ESW= 6.0 V vs. Ag+/Ag). In consequence, the hyperbranched poly(triazolium)s could act as the new conductive materials.The branched triazole with low Mn was sybthesized by the click chemistry via slow addition of AB2 monomer to B2 core, then the branched triazole was connect to the 1,6-heptadiyne, to get the macromonomer MDTA, which underwent the metathesis cyclopolymerization (MCP) under the catalization of Ru-Ⅲ, to obtain the trans-poly(MDTA) having solely five-membered ring repeating units. The LiTFSI and I2 doping manner realize the preparation of ionic and electronic mixed conductive material. The LiTFSI doped poly(MDTA) showed the ionic conductivity of 2.5 × 10-6,2.2 × 10-6 and 1.77 × 10-6 S/cm at the optimal doping ratio r= 0.033, which decreased with the increasing of Mn. To improve the electronic conductivity of poly(MDTA), the polymers were doped with I2, and the highest ionic and electronic conductivity were 1.25 × 10-5 and 2.1 × 10-7 S/cm, and the ionic and electronic conductivity of polymers were positively related, hence, the increasment of ionic conductivity was benefit for the enhance the electronic conductivity.At last, the branched triazolium was introduced into 1,6-heptadiyne, to get the mono- and bis-substituted macromonomer [MDTA]+[TFSI]- and [DDTA]+[TFSI]-, respectively. Followed by the MCP reaction initiated with Ru-Ⅲ, the trans-PA ionomers poly[MDTA]+[TFSI]- and poly[DDTA]+[TFSI]- with five-membered ring repeating units were obtained. The conductivity of polymers at their intrinsic state and doped state (LiTFSI and I2 doped) was investigated. The highest intrinsic ionic conductivity of poly[MDTA]+[TFSI]- was 1.93×10-5 S/cm, and the poly[DDTA]+[TFSI]- showed the ionic conductivity of 2.11×10-5 S/cm. After doping with LiTFSI (r= 0.033), the polymer displayed the highest ionic conductivity of 4.26 × 10-5 S/cm at 30℃. Similarly, the polymers were doped with I2, and the highest ionic and electronic conductivity were 7.1 × 10-4 and 4.5 × 10-6 S/cm, about an order of magnitude higher than these of doped poly(MDTA).In brief, by combination the advantage of triazole, triazolium, and polyacetylene, a series of polymers with stimuli responsive or conductive prpoerties were abtained, which provided a reference for the preparation of materials with multifunctionality.