Diazide Monomers Research Articles

Synthesis, Antibacterial Activity, and Cytotoxicity of Azido-Propargyloxy 1,3,5-Triazine Derivatives and Hyperbranched Polymers

A new method for the synthesis of azido-propargyloxy derivatives of 1,3,5-triazine has been developed utilizing the nitrosation of hydrazyno-1,3,5-triazines. New hydrazines (2-hydrazino-4,6-bis(propargyloxy)-1,3,5-triazine and 2,4-dihydrazino-6-propargyloxy-1,3,5-triazine) were synthesized and characterized via FTIR, NMR spectroscopy and elemental analysis. The hyperbranched polymers with azide (diazide monomer) and propargyloxy terminal groups were obtained via the azide-alkyne polycycloaddition reaction of diazide and monoazide AB2-type monomers. The antibacterial activity against Escherichia coli bacteria of 2,4,6-trispropargyloxy-1,3,5-triazine, 2-azido-4,6-bispropargyloxy-1,3,5-triazine, and 2,4-diazido-6-propargyloxy-1,3,5-triazine and their hyperbranched polymers was studied. Only 2,4-diazido-6-propargyloxy-1,3,5-triazine has weak antibacterial activity in comparison with ampicillin. The cytotoxicity of these compounds against M-HeLa, FetMSC, and Vero cell lines was also studied. 2,4,6-trispropargyloxy-1,3,5-triazine does not show any cytotoxic effect (IC50 ≥ 280 µM). It was shown that the presence of an azide group in the compound directly affects the cytotoxic effect. Hyperbranched polymers have a less cytotoxic effect against M-HeLa (IC50 > 100) in comparison with monomers (IC50 = 90–99 µM). This makes it possible to use these polymers as the basis for biocompatible materials in biomedical applications.

Charge-conversional click polyprodrug nanomedicine for targeted and synergistic cancer therapy.

Polyprodrug nanomedicines hold great potential for combating tumors. However, the functionalization of polyprodrug nanomedicines to improve therapeutic efficacy is restricted by conventional polymerization methods. Herein, we fabricated a charge-conversional click polyprodrug nanomedicine system by metal-free azide-alkyne cycloaddition click polymerization (AACCP) for targeted and synergistic cancer therapy. Specifically, Pt(IV) prodrug-backboned diazide monomer, DMC prodrug-pendent diazide monomer, dialkyne-terminated PEG monomer and azide-modified folate were click polymerized to obtain the target polyprodrug (P1). P1 could self-assemble into nano-micelles (1-NM), where PEG was the hydrophilic shell with folate on the surface, Pt(IV) and DMC prodrugs as the hydrophobic core. Taking advantage of PEGylation and folate-mediated tumor cell targeting, 1-NM achieved prolonged blood circulation time and high tumor accumulation efficiency. Tumor acidic microenvironment-responsive cleavage and cascade activation of pendant DMC prodrug induced surface charge conversion of 1-NM from negative to positive, which promoted tumor penetration and cellular internalization of the remaining 1-NM. After internalization into tumor cells, the reduction-responsive activation of Pt(IV) prodrug to Pt(II) further showed synergetic effect with DMC for enhanced apoptosis. This first designed charge-conversional click polyprodrug nanomedicine exhibited targeted and synergistic efficacy to suppress tumor proliferation in living mice bearing human ovarian tumor model.

Synthesis and characterization of sulfonated polytriazoles utilizing 1,4‐bis(4‐azido‐2‐(trifluoromethyl)phenoxy)benzene for the proton exchange membrane applications

AbstractThe aromatic hydrocarbon‐based sulfonated polytriazoles have a reputation as a high‐performing polymer because of their excellent properties. This work demonstrates the synthesis of a new semi‐fluorinated diazide monomer, that is, 1,4‐bis(4‐azido‐2‐(trifluoromethyl)phenoxy)benzene (BATFB), and exploiting this compound a series of aromatic hydrocarbon‐based semi‐fluorinated sulfonated polytriazoles (BABPSSH‐60, −70, −80, −90) was synthesized utilizing the Cu(I)‐induced “click” cycloaddition polymerization reaction along with the sulfonated diazide monomer, 4,4′‐diazido‐2,2′‐stilbenesulfonic acid disodium salt tetrahydrate (DASSA) and the terminal dialkyne monomer, 4,4′‐(propane‐2,2′‐diyl)bis((prop‐2‐ynyloxy)benzene) (BPAAL). The structural analysis of those copolymers was completed by the FTIR and the NMR (1H and 13C) spectroscopic methods. Further, the degree of sulfonation (DS) and the ion exchange capacity (IEC) values of the copolymers were confirmed using the 1H NMR spectrums. They are readily soluble in respective solvents, and a light yellowish membrane was obtained using the solution casting procedure. These membranes demonstrated admissible mechanical and thermal stabilities, balanced water absorption properties, and reasonable chemical stability. The surface phase (SAXS, AFM) and bulk phase (TEM) morphological analysis proved the well‐separated phase morphology. The BABPSSH‐90 displayed a proton conductivity of 104 mS cm−1 at 90.

Trifluoromethyl functionalized sulfonated polytriazoles from diphenylphosphine oxide-based dialkyne via click polymerization: Effect of high content of phosphorus on the proton exchange membrane properties

A new diphenylphosphine oxide based dialkyne, [2,5-bis(prop-2-yn-1-yloxy)phenyl]diphenylphosphine oxide (POALK) has been prepared under mild reaction conditions. Using this POALK monomer, a new-fangled fluorinated sulfonated polytriazoles (PTPPS-70 to -90 and PTPS-100) with a high content of phosphine oxide moieties were prepared via the click polymerizations with other two comonomers [sulfonated diazide (DSAZ) and non-sulfonated phosphorus containing diazide (PFAZ)]. FT-IR and NMR (1H, 13C, and 31P) spectroscopic techniques were used for the structural elucidations of the synthesized monomer and polymers. The high molecular weight (weight average molecular weight: 59,600–75,800 g mol−1 and PDI: 1.65–2.20) sulfonated polymers demonstrated exceptional thermal, mechanical and thermomechanical steadiness. The higher content of phosphorus (3.83–4.54%) in the copolymers (IECW: 1.58–2.16 meq g−1) has occasioned excellent harmony among the water uptakes (WU), swelling ratios (SR), and proton conductivity (σ). The coexistence of triarylphosphine oxide units (both in the dialkyne and diazide monomers) in the polymers slowed down the peroxide radical attacks. The observed interconnected ionic nanochannels in the phase segregated morphology in AFM and TEM images of sulfonated polytriazoles (PTPPS-70 to -90 and PTPS-100) facilitate the proton transportation that resulted in high proton conductivity.

Flame‐retardant, phosphorous‐based polyurethane triazoles via solvent‐free and catalyst‐free azide–alkyne cycloaddition and their cure kinetics

A novel class of phosphorous‐containing polyurethane triazoles (PUTs) with self‐extinguishing property is reported. Initially, a set of new urethane diazide monomers were synthesized by reacting diisocyanates (DI) (isophorone (IPDI), hexamethylene (HDI), and toluene (TDI)) with 2‐azidoethanol and characterized by FTIR, 1H NMR, 13C NMR, and ESI‐MS analysis. Later, the corresponding PUTs were synthesized via azide–alkyne cycloaddition of urethane diazides with triprop‐2‐ynyl phosphate under solvent‐free and catalyst‐free conditions at 80°C via thermal polymerization. Cure kinetic study of the thermally induced polymerization of PUTs was performed to correlate with isocyanate functionality. The activation energies (Ea) of the PUTs derived from nonisothermal multiheating rate DSC tests were fitted to Borchardt–Daniels model. The Ea's were found to be proportional to heating rates for all PUTs and confirmed optimum percentage conversion at lower heating rates. The experimental findings were found to corroborate well with Borchardt–Daniels model. The PUTs were characterized by FTIR, TGA, DSC, MCC, LOI, lab‐scale flame tests, and EDX analysis. All PUTs were self‐extinguishable, but TD‐PUT with aromatic functionality (TDI‐based) demonstrated superior extinguishing performance with lowest total heat release (6.11 kJ/g), peak heat release rate (42.04 W/g), heat release capacity (85.59 J/g K), and 31% LOI comparatively. Lab‐scale flame tests on PUTs confirmed their self‐extinguishing property with little or no smoke evolution. Such PUT resins can be blended with conventional polyurethane coatings for fire‐retardant applications.

Effects of network structures on the tensile toughness of copper-catalyzed azide-alkyne cycloaddition (CuAAC)-based photopolymers.

In the present study, the photo-initiated copper-catalyzed azide-alkyne cycloaddition (CuAAC) polymerization was utilized to form structurally diverse glassy polymer networks. Systematic alterations in the monomer backbone rigidity (e.g., cyclic or aliphatic groups with a different length of backbone) and the reactive functional group density (e.g., tetra-, tri-, di-, and mono-functional azide and alkyne monomers) were used to provide readily tailorable network structures with crosslink densities (estimated from the rubbery modulus) varying by a factor of over 20. All eight of the resultant networks exhibited glass transition temperatures (Tg) between 50 and 80 °C with tensile toughness ranging from 28 to 61 MJ m-3. A nearly linear dependence of yield stress and elongation at break (broadly defined as strength and ductility, respectively) on the Tg and rubbery modulus was established in these triazole networks. When a flexible di-alkyne monomer (5 carbon spacing between alkynes) was incorporated in a network composed of a tri-alkyne and di-azide monomer, the elongation at break was improved from 166 to 300 %, while the yield stress was reduced from 36 to 23 MPa. Additionally, the polymer ductility was also varied by incorporating mono-functional azides as chain ends in the network - replacing a sterically hindered stiff mono-azide with a more flexible mono-azide increased the elongation at break from 24 to 185 % and the tensile toughness from 6 to 28 MJ m-3.

Synthesis of 2,2′-hindered pyridine containing semifluorinated polytriazoles and investigation for low-temperature proton exchange membrane application with enhanced oxidative stability

A series of new sulfonated copolytriazoles were prepared from a novel fluorinated diazide monomer with pyridine moiety to enhance both the oxidative stability and proton conductivity of proton exchange membranes. These proton donor–acceptor based copolymers and homopolymers were synthesized by click cycloaddition polymerization of the dialkyne monomer 1,2,4,5-tetrafluoro-3,6-bis(prop-2-yn-1-yloxy)benzene (TFAK) with or without the pyridine containing diazide monomer 2,2′-bis(4-(4-azidophenoxy)-3-(trifluoromethyl)phenyl)pyridine (PYFAZ) and the sulfonated diazide monomer 4,4′-diazido-2,2′-stilbenedisulfonic acid disodium salt (DSSAZ). 1H, 13C, and 19F NMR, in addition to FTIR analyses, confirm the formation of polytriazoles with a graded degree of sulfonation between 70% and 100%. The solution cast membranes were flexible and showed high chemical, thermal and mechanical properties. Inclusion of pyridine moiety proved to play a significant role in increasing peroxide stability by quenching hydroxyl and hydroperoxide radicals and forming pyridine-N-oxide, which was analyzed by EPR and FTIR spectroscopy. The presence of pyridine moiety also enhanced proton conductivity owing to the presence of the weakly basic nitrogen in pyridine that acts as a proton hopping site. AFM and HR-TEM images of the membranes indicated the formation of phase-separated morphology and that became more pronounced with the increase in the degree of sulfonation. The membranes obtained from PYFTSH-90 copolymer exhibited proton conductivity of 125 mS cm−1 at 80 °C, which is comparable to Nafion-117. The proton conductivity of PYFTSH-90 was further increased to 139 mS cm−1 at 90 °C. Thus, three significant objectives have been fulfilled in this work, namely (i) high proton conductivity, (ii) high hydrolytic stability, and (iii) high peroxide stability. These properties demonstrate that these copolymer membranes are potentially highly suitable for application in low-temperature proton exchange membrane fuel cell (PEMFC).

Synthesis and Characterization of New Phosphorus Containing Sulfonated Polytriazoles for Proton Exchange Membrane Application

ABSTRACTSulfonated polytriazoles have drawn a great attention as high performance polymers and their good film forming ability. In the present study, a phosphorus containing new diazide monomer namely, bis‐[4‐(4′‐aminophenoxy)phenyl]phenylphosphine was synthesized and accordingly, a series of phosphorus containing sulfonated polytriazoles (PTPBSH‐XX) was synthesized by reacting equimolar amount of this diazide monomer (PAZ) in combination with another sulfonated diazide monomer (DSAZ) and a terminal bis‐alkyne (BPALK) by the Cu (I) catalyzed azide–alkyne click polymerization. The polymers were characterized by nuclear magnetic resonance (1H, 13C, 31P NMR) and Fourier transform infrared spectroscopic techniques. The sulfonic acid content of the copolymers also determined from the different integral values obtained from the 1H NMR signals. The small‐angle X‐ray scattering results unfolded the well‐separated dispersion of the hydrophilic and hydrophobic domains of the polymers. As a whole, the copolymer membranes displayed sufficient thermal, mechanical, and oxidative stabilities high with high proton conductivity and low water uptake that are essential for proton exchange membrane applications. The copolymers exhibited oxidative stability in the range of 15–24 h and had proton conductivity values were found as high as 38–110 mS cm−1 at 80 °C in completely hydrated condition. Among the all copolytriazoles, PTPBSH‐90 (BPALK:DSAZ:PAZ = 100:90:10) having IECW = 2.44 mequiv g−1, showed proton conductivity as high as 119 mS cm−1 at 90 °C with an activation energy of 10.40 kJ mol−1 for the proton conduction. © 2020 Wiley Periodicals, Inc. J. Polym. Sci. 2020, 58, 263–279

Synthesis and characterization of new sulfonated copolytriazoles and their proton exchange membrane properties

ABSTRACTThis work reports the synthesis and characterization of a series of new sulfonated copolytriazoles. The polymers were prepared by CuI catalyzed 1,3‐cycloaddition reaction of an equimolar amount of a dialkyne monomer, 1,3‐diethynylbenzene and a mixture of two diazide monomers, namely, 4,4′‐diazidodiphenyl ether and 4,4′‐diazido‐2,2′‐stilbenedisulfonic acid disodium salt. The copolymers showed high inherent viscosity indicating the formation of high molar mass product. The copolymers were characterized by Fourier transform infrared and proton nuclear magnetic resonance spectroscopic techniques. The copolymer membranes displayed moderate water uptake, high dimensional, mechanical, and thermal stability. Transmission electron microscopy micrographs displayed excellent phase‐separated morphology along with very fine ionic clusters. The copolymer PTEOSH‐90 (90% degree of sulfonation) showed much higher proton conductivity value which is up to 196 mS cm−1 at 80 °C in completely hydrated condition compared to that of Nafion (165 mS cm−1). © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48514.

Synthesis and characterization of chemically stable sulfonated copoly(triazole imide)s with high proton conductivity

The synthesis and characterization of a series of new sulfonated copoly(triazole imide)s (PTPQSH‐XX) are reported in this work. The PTPQSH‐XX with different degree of sulfonation (DS) were prepared by click polymerization of equimolar amounts of a diimide‐based dialkyne monomer, namely bis‐N,N′‐(prop‐2‐ynyl)pyromellitic diimide (TP) and a mixture of two different diazide monomers (one sulfonated, 4,4‐bis[3′‐trifluoromethyl‐4′{4‐azidobenzoxy} benzyl] biphenyl, and another nonsulfonated, 4,4′‐diazido‐2,2′‐stilbene disulfonic acid disodium salt [SAZ]), in different molar ratios. The copolymers showed high inherent viscosity (1.12–1.28 dL/g) in n‐methyl pyrrolidone (NMP) indicating the formation of high molar masses. Freestanding membranes were prepared from these copolymers by solution casting method. DS of the copolymers was determined from 1H NMR signal intensities, and the values were in good agreement with the quantity of SAZ monomer used in polymer feed, indicating the successful incorporation of the sulfonated monomer. The copolymers exhibited high thermal and mechanical stabilities. The PTPQSH‐80 membrane showed proton conductivity as high as 178 mS/cm at 90°C with good oxidative and hydrolytic stability. Cross‐sectional transmission electron microscope micrographs of the membranes indicated phase segregated morphology along with interconnected hydrophilic domains with dimension in the range 15–150 nm. POLYM. ENG. SCI., 59:2279–2289, 2019. © 2019 Society of Plastics Engineers

Ionene copolymer electrolyte obtained from cyclo-addition of di-alkyne and di-azide monomers for solid-state smart glass windows

A copoly(ionic liquid) (coPIL) based on 1,2,3-triazolium bearing trioxyethylene and tetraoxyethylene spacers was successfully synthesized as electrolyte for all-solid state electrochromic devices (ECD). This polyelectrolyte was produced by reacting triethylene glycol (TEG3)-diazide and tetraethylene glycol (TEG4)-dialkyne monomers through a ‘click’ reaction, copper-catalyzed alkyne-azidecycloadditon (CuAAC), and subsequently underwent several alkylation and anion metathesis. The new coPIL bearing ethylene glycol fragments exhibited excellent thermal degradation temperature (Td10 = 230 °C) and ionic conductivity (σ = 8.8 × 10−5 S cm−1) which resulted to an efficient color switching (tc = 11.8 s and tb = 6.2 s), a high optical contrast (ΔT = 24%) and a remarkable stability (after 3000 cycles) of a symmetric all-solid-state smart glass window. The structural design of this new polyelectrolyte material and its corresponding properties make it an excellent electrolyte for many electrochemical devices that require zero electrolyte leakage.

Synthesis and Characterization of Highly Proton Conducting Sulfonated Polytriazoles

This article describes the synthesis and characterization of highly sulfonated polytriazole copolymers (PTSQSH-I to IV) with IECw values ranging from 2.41 to 3.49 mequiv g–1. The copolymers were synthesized by click reaction between equimolar amount of a dialkyne monomer, potassium 2,5-bis(2-propyn-1-yloxy)benzenesulfonate, and a mixture of two different diazide monomers, 4,4-bis[3′-trifluoromethyl-4′(4-azidobenzoxy)benzyl]biphenyl and 4,4′-diazido-2,2′-stilbene disulfonic acid disodium salt. The copolymers were characterized by Fourier transform infrared and NMR spectroscopy techniques. The membranes were prepared by dissolving the salt form of the copolymers in dimethyl sulfoxide. The copolymers showed high thermal, mechanical, and oxidative stabilities, and the acidified membranes showed very high proton conductivity (43–173 and 132–304 mS cm–1 at 30 and 80 °C, respectively). Transmission electron microscopy images confirmed the formation of well-phase-separated morphology with interconnected hydrophilic domains (20–150 nm).

New crosslinked sulfonated polytriazoles: Proton exchange properties and microbial fuel cell performance

The synthesis, characterization and establishment of the structure-property relationship of a series of new semifluorinated sulfonated polytriazoles (PTCTSH-XX) with varying degrees of sulfonation are described. The polymers were synthesized by the click polymerization reaction of a mixture of two diazide monomers, the non-sulfonated diazide monomer 4,4-bis[3-trifluoromethyl-4(4-azidophenoxy) phenyl]benzene (TAZ) and the sulfonated diazide monomer 4,4′-diazido-2,2′-stilbenedisulfonic acid disodium salt (SAZ), with an equimolar amount of the dialkyne monomer 3,5-bis(prop-2-ynyloxy)benzoic acid (BPBA). The polytriazoles were characterized by 1H and 13C NMR spectroscopy. All the polymers showed good solubility in selected polar aprotic organic solvents along with excellent film forming ability. The TEM micrographs of these polymers exhibited a uniformly phase separated morphology. The polymers showed very high proton conductivity and the values were within the range of 15–67 mS cm−1 at 30 °C, 38–163 mS cm−1 at 80 °C and 42–176 mS cm−1 at 90 °C in hydrated condition. The pristine polymers were crosslinked with poly(vinyl alcohol) and their PEM properties were also investigated. The crosslinked films showed lower water uptake and dimensional swelling and improved oxidative stability in comparison to the pristine membranes. The microbial fuel cell performance of both pristine and crosslinked membranes was also investigated.

New 1,2,3-Triazole Containing PolyestersviaClick Step-Growth Polymerization and Nanoparticles Made of Them

High-molecular-weight AA-BB-type aliphatic polyesters were synthesizedviaCu(I)-catalyzed click step-growth polymerization (SGP) following a new synthetic strategy. The synthesis was performed between diyne and diazide monomers in an organic solvent as one pot process using three components and two stages. The dipropargyl esters of dicarboxylic acids (component 1) were used as diyne monomers, di-(bromoacetic acid)-alkylene diesters (component 2) were used as precursors of diazide monomers, and sodium azide (component 3) was used for generating diazide monomers. The SGP was carried out in two steps: at Step 1 dibromoacetates interacted with two moles of sodium azide resulting in diazide monomers which interacted in situ with diyne monomers at Step 2 in the presence of Cu(I) catalyst. A systematic study was done for optimizing the multiparameter click SGP in terms of the solvent, duration of both Step 1 and Step 2, solution concentration, catalyst concentration, catalyst and catalyst activator (ligand) nature, catalyst/ligand mole ratio, and temperature of both steps of the click SGP. As a result, high-molecular-weight (MWup to 74 kDa) elastic film-forming click polyesters were obtained. The new polymers were found suitable for fabricating biodegradable nanoparticles, which are promising as drug delivery containers in nanotherapy.

Flexible Diazide Based Sulfonated Polytriazoles and Their Proton Exchange Membrane Properties

The preparation, characterization, and property evaluation of a series of new semifluorinated polytriazoles (PTEHSH‐XX) with various degrees of sulfonation is described. The polymers are synthesized by the click polymerization reaction of a mixture of a new diazide monomer, 1,4‐bis‐[{2′‐trifluromethyl 4′‐(4″‐azidophenyl)phenoxy}]phenyl, and a sulfonated monomer, 4,4′‐diazido‐2,2′‐stilbenedisulfonic acid disodium salt, with an equimolar amount of a dialkyne monomer, 1,3‐diethynylbenzene. The polytriazoles are characterized by Fourier transform infrared spectroscopy (FTIR) and NMR spectroscopic techniques. The polytriazoles show good solubility in selective organic solvents and film forming ability. The films prepared from these polymers show high thermal and chemical stability, low water uptake, high dimensional stability, and excellent mechanical properties. The transmission electron microscopy images of these polymers exhibit a uniformly phase separated morphology. The polymers show very high proton conductivity and the values are within the range of 27–118 mS cm−1 at 30 °C, 53–225 mS cm−1 at 80 °C, and 58–235 mS cm−1 at 90 °C in hydrated condition. image

Synthesis and performance study of a novel sulfonated polytriazole proton exchange membrane

Sulfonated polytriazole (SPTA) proton exchange membranes (PEMs) with a series of sulfonation degrees was synthesized based on click chemistry from a rigid diazide monomer, 4,4′-bis(azidomethyl)-1,1′-biphenyl (BAMB), with 2,2-bis[(4-propargyloxy)phenyl]propane (BPBPA) and 4,4′-diazido-2,2′-stilbenedisulfonic acid disodium salt (DSDA). The structure of the copolymers was characterized by nuclear magnetic resonance (NMR) and gel permeation chromatography (GPC). As a result of the introduction of rigid biphenyl structure and the ionic interaction between triazole rings and sulfonic acid groups, the SPTA membranes exhibited higher water uptake and lower swelling ratio compared to NRE211 membrane, indicating excellent dimensional stability. AC impedance revealed that the proton conductivity of SPTA membranes ranged from 2.5 to 35 mS/cm at 30 °C and 13–105 mS/cm at 80 °C. Besides, the membranes have high thermal and oxidative stability, good mechanical property, and low methanol permeability as well.

Synthesis, characterization and investigation of proton exchange properties of sulfonated polytriazoles from a new semifluorinated diazide monomer

This work describes the synthesis and characterization of a new series of semifluorinated sulfonated polytriazole copolymers (PTATSH‐XX) with varying degree of sulfonation and higher IEC. The copolymers have been prepared by click reaction using a combination of diazide monomers; a newly synthesized diazide monomer namely 4,4‐bis[3‐trifluoromethyl‐4(4‐azidophenoxy)phenyl]benzene (TAZ) and a commercially available diazide monomer namely 4,4′‐diazido‐2,2′‐stilbenedisulfonic acid disodium salt (DADSDB) with a bis‐alkyne monomer namely 4,4′‐(propane‐2,2‐diyl)bis((prop‐2‐ynyloxy)benzene) (BPEBPA). The copolymers are well characterized by FTIR and NMR spectroscopy and have exhibited good solubility and film forming abilities along with good thermal and chemical stability, low water uptake, good dimensional stability and high mechanical properties. The TEM micrographs of the copolymer membranes show good phase separated morphology with cluster size in the range 10–60 nm. The proton conductivity values of the copolymer membranes are found in the range of 15–90 mS cm−1 at 80°C and 16–97 mS cm−1 at 90°C. POLYM. ENG. SCI., 57:312–323, 2017. © 2016 Society of Plastics Engineers

Polymers functionalized with 1,2-benzenedithiolate-bridged model compound of [FeFe]-hydrogenase: Synthesis, characterization and their catalytic activity

Three polymers functionalized with 1,2-benzenedithiolate-bridged diiron carbonyl units, Polymers 1–3, were prepared by using three diazide monomers with different organic frames via “click chemistry”. These polymers were characterized by IR spectroscopy, thermal gravimetric analysis, scanning electron microscopy and electrochemistry. Their solubility, morphology and catalysis on proton reduction are largely controlled by the organic moieties of the diazides. The presence of carboxylates in Polymer 3 causes significant difference both physically and chemically (electrochemically). It is soluble in water but decomposes rapidly in DMSO. Its stability is much improved after being assembled into membrane electrodes. The electrodes assembled from these polymers are relatively robust and all operational in water. The carboxylate in Polymer 3 turns out a better proton-relay in catalysis by exhibiting higher catalytic efficiency in both solution and solid state (membrane electrode).

Synthesis and characterization of highly fluorinated sulfonated polytriazoles for proton exchange membrane application

A series of polytriazole copolymers were synthesized by the click polymerization of fluorinated dialkyne with a mixture of two different diazide monomers and the proton exchange membrane properties of the copolymers were investigated.

Mechanical, thermal and electrical properties of polyimides containing 1, 2, 3-triazole ring prepared by click reaction

4-Aminophenyl propargyl ether (APPE) containing alkynyl group and diazide monomers were synthesized for the click reaction. 1, 2, 3-triazole-containing diamine monomers were synthesized by the 1, 3-dipolar cycloaddition reaction in the presence of Cu (I) catalyst by click reaction which was used to prepare a novel polyimide containing 1, 2, 3-triazole ring (polytriazoleimide) by polycondensation reaction with aromatic dianhydride. The chemical structure of the monomers and polymers was confirmed by FT-IR, 1H-NMR and 13C-NMR spectral techniques. Polytriazoleimides exhibit low dielectric constant of 2.74–3.12 at 1 MHz, high thermal stability, the temperature corresponding to a 5 % weight loss from (441–473 °C) and good flame retardancy (LOI value 35.6–38.8). Glass transition temperature was observed to be between 218 and 248 °C and storage modulus between 2.61 and 3.54 GPa. These polymers are readily soluble in highly polar organic solvents. Furthermore, the incorporation of 1, 2, 3-triazole significantly improves the glass transition temperature, thermal stability and storage modulus of the polymer. Hence the click coupling is an effective approach to develop the structural and functional polyimides.