Thioether Ketone Research Articles

Synthesis of sulfonated poly(fluorenyl ether thioether ketone)s with bulky-block structure and its application in vanadium redox flow battery

High-molecular-weight bulky-block poly(fluorenyl ether thioether ketone)s were successfully synthesized by a two steps one-pot protocol using N,N′-dimethy- S-carbamate masked dithiols for vanadium redox flow battery (VRB) application. The followed sulfonation procedure gave birth to novel sulfonated block poly(fluorenyl ether thioether ketone)s (SPFETKs) with controlled ionic exchange capacities (IEC). Membranes with proton conductivities higher than (IEC > 1.66 mequiv. g −1) or comparable to (IEC < 1.66 mequiv. g −1) that of Nafion117 membrane were achieved. The VO 2+ permeabilities of SPFETKs membranes were much lower than that of Nafion117 membrane. The thermal properties, mechanical properties, oxidative stability, water uptake, proton conductivity, VO 2+ permeability and cell performance were investigated in detail.

Synthesis and characterization of novel sulfonated poly(arylene thioether) ionomers for vanadiumredox flow battery applications

High-molecular-weight poly(arylene thioether ketone) (PTK) and poly(arylene thioether ketone ketone) (PTKK) polymers were successfully synthesized by one-pot polymerization of N,N′-dimethy-S-carbamate masked dithiols with activated dihalo compounds, followed by post-sulfonation using chlorosulfonic acid as the sulfonation agent in dichloromethane solution to give the production of sulfonated poly(arylene thioether ketone) (SPTK) and sulfonated poly(arylene thioether ketone ketone) (SPTKK) with appropriate ion-exchange capacities. The chemical structures were confirmed by 1H NMR, FT-IR and elemental analysis (EA). The thermal properties were fully investigated by TGA-IR. The synthesized SPTK and SPTKK polymers are soluble in aprotic solvents such as N,N′-dimethylacetamide (DMAc), N,N′-dimethylformamide and dimethyl sulfoxide, and can be cast into membranes on a glass plate from their DMAc solution. The proton conductivities of these membranes are comparable to Nafion117 membranes under the same conditions. Cell performance tests showed that the vanadium redox flow batteries (VRBs) assembled with SPTK and SPTKK membranes possessed higher Coulombic efficiencies than VRBs assembled with Nafion117 membranes at the current density of 50 mA cm−2, because of their one-order-of magnitude lower VO2+ permeabilities. In conclusion, these ionomers could be promising candidates as proton-exchange membranes for vanadium redox flow battery (VRB) applications.

Preparation and characterisation of novel random copoly(arylene ether–thioether ketone)s containing 2,2-bis(4-phenylene)propane units

This study investigates on the preparation and characterisation of new random copolymers containing the monomeric units of a poly(arylene ether ketone) (PEAEK) and a poly(arylene thioether ketone) (PTATK) previously synthesised by our group. The syntheses were performed using a one-pot polymerisation method starting from 4,4′-difluorobenzophenone, bis( N, N-dimethyl- S-carbamate) of 2,2-bis(4-mercaptophenyl)propane (MBTA) and bisphenol A (BPA). Different mole percentages of BPA with respect to MBTA, varying from 20% to 80%, were used. The copolymers, obtained in good yields, have molecular weights in the range from 19,000 to 32,000 as determined by GPC. The structural proof is provided by 1H NMR spectroscopy. The TGA analysis shows that the high stability of PEAEK is only slightly affected by the introduction of the PTATK co-units in the chain. Indeed, the presence of sulphur atoms induces an initial degradation process at temperatures slightly lower than that of PEAEK, but in a second stage tends to improve the formation of crosslinkings. Moreover, the copolymers with an amount of PEAEK equal to 40 and 20 mol% show a small crystallinity, due to the presence of PTATK units. The T g values are not affected by the composition of copolymers. Therefore, the presence of sulphur atoms in the polymer backbone does not significantly modify the PEAEK characteristics, whereas can induce important new properties, such as better flame resistance or higher refractive index.

Synthesis and ring-opening polymerization of macrocyclic (arylene thioether ketone) oligomers

Macrocyclic (arylene thioether ketone) oligomers together with a linear poly(phenylene sulfide ketone) oligomer were synthesized by a one-step reaction. The macrocycles and linear oligomer were fully characterized by 13C-NMR, H-NMR, matrix assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS), differential scanning calorimetry (DSC) and FT-IR. Uncatalyzed, simultaneously ring-opening polymerization (ROP) of the macrocycles and the mixture of macrocycles and linear oligomer were carried out under dynamic heating conditions. The ROP temperature of the macrocycles decreased upon mixing it with the linear oligomer. The ROP conditions and mechanism were investigated and discussed. The macrocycles and their mixture show potential applications in high temperature adhesives and sealants. Copyright © 2006 John Wiley & Sons, Ltd.

One step synthesis and rapid ring-opening polymerization of macrocyclic (arylene thioether ketone) oligomers

Well-crystal macrocyclic (arylene thioether ketone) oligomers were synthesized under high dilution condition by the reaction of Na2S with bis(4-fluoro-phenyl)-methanone in 1-methyl-pyrrolidone (NMP). The oligomers were fully characterized by Matrix-assisted laser desorption/ionization time-of-flight mass spectra (MALDI-TOF-MS), high-pressure liquid chromatography (HPLC), gel permeation chromatography (GPC), 1H NMR, 13C-NMR, and differential scanning calorimetry (DSC). According to DSC studies, uncatalyzed and rapid ring-opening polymerization (ROP) of the oligomers took place instantly when they were heated to melting point. Extracted by dichloro-methane, the obtained polymer neither loses any weight nor dissolves in boiling 1-chloro- naphthalene. These facts indicated that there are no residual oligomers within the resultant polymer. The as-prepared oligomers could be potentially used as high-temperature hot-melt adhesive at a high temperature > 350°C, and matrices for high-performance composites and nanocomposites. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 161–166, 2006

Crystal and molecular structure of the thioether-analogue of PEEK from X-ray powder data and diffraction-modelling

Analysis of X-ray powder data for the melt-crystallisable aromatic poly(thioether thioether ketone) [–S–Ar–S–Ar–CO–Ar] n , (‘PTTK’, Ar=1,4-phenylene), reveals that it adopts a crystal structure very different from that established for its ether-analogue PEEK. Molecular modelling and diffraction-simulation studies of PTTK show that the structure of this polymer is analogous to that of melt-crystallised poly(thioetherketone) [–S–Ar–CO–Ar] n in which the carbonyl linkages in symmetry-related chains are aligned anti-parallel to one another, and that these bridging units are crystallographically interchangeable. The final model for the crystal structure of PTTK is thus disordered, in the monoclinic space group I2/ a (two chains per unit cell), with cell dimensions a=7.83, b=6.06, c=10.35 Å, β=93.47°.

Sulfonated poly(arylene thioether ketone ketone sulfone)s for proton exchange membranes with high oxidative stability

Abstract Sulfonated poly(arylene thioether ketone ketone sulfone)s (SPATKKS) were synthesized by nucleophilic polycondensation of various amounts of 1,3- bis(4-fluorobenzoyl)benzene, 1,3-bis(3-sodium sulfonate-4-fluorobenzoyl)benzene, and 4,4’-dichlorodiphenylsulfone with 4,4’-thiobisbenzenethiol. Sulfonated poly- (arylene ether ketone ketone sulfone)s were also prepared in order to compare their oxidation resistance to peroxides with that of SPATKKS. SPATKKS show high oxidation resistance to peroxides. The resulting ionomers with moderate ion exchange capacity present excellent thermal stability (the 5% weight loss temperature is about 500°C) and low water uptake and swelling ratio until 85°C. The materials hold promise for application as proton exchange membranes in fuel cells.

Sulfur-containing polymers. Synthesis and properties of novel poly(arylene thioether)s based on 2,2-bis(4-mercaptophenyl)propane

Novel poly(arylene thioether)s were synthesised using the one pot polymerisation method from the bis( N,N-dimethyl-S-carbamate) of 2,2-bis(4-mercaptophenyl)propane and activated difluoro aromatic compounds. Each of the polymers, obtained in good yields and with fairly high molecular weights, were characterised by IR, GPC and NMR analyses. In particular, the NMR characterisation was performed using 1H NMR, 13C NMR, DEPT, 2D COSY and 2D HSQC experiments. To study the effect on the thermal properties of replacing the ethereal oxygen atoms with sulfur atoms, we have synthesised the counterparts, the poly(arylene ether)s, with similar molecular weights. We observed that the substitution of the ethereal oxygen atoms with sulfur atoms results in a slightly lower thermal stability for the poly(thioether ketone)s, both under nitrogen and in air, and does not modify the T g values. For the poly(thioether sulfone), on the other hand, the thermal stability is equal to that of the poly(ether sulfone), while the T g is 10 °C lower. Furthermore, each sample is completely amorphous, with the exception of one of the poly(thioether ketone)s (sample 1b), which shows the capacity to crystallise, even if with a very slow crystallisation kinetics.

Spontaneous Ring‐Opening Polymerization of Macrocyclic Aromatic Thioether Ketones under Transient High‐Temperature Conditions

AbstractSummary: Spontaneous ring‐opening polymerization of macrocyclic aromatic thioether ketones [1,4‐SC6H4COC6H4]n (n = 3 and 4), in which the thioether linkages are para to the ketone, occurs during rapid, transient heating to 480 °C, to afford a soluble, semi‐crystalline poly(thioether ketone) of high molar mass (ηinh &gt; 1.0 dL · g−1). Corresponding macrocyclic ether ketones, and a macrocyclic thioether ether ketone in which the thioether linkage is para to the ether rather than to the ketone, show no evidence of polymerization under analogous conditions.The uncatalysed ring‐opening polymerization of macrocycle 1, within the pores of an alumina microfiltration membrane, leads to formation of polymer 3 with the microstructure shown in the above scanning electron micrograph.magnified imageThe uncatalysed ring‐opening polymerization of macrocycle 1, within the pores of an alumina microfiltration membrane, leads to formation of polymer 3 with the microstructure shown in the above scanning electron micrograph.

Rapid, Uncatalyzed Ring-Opening Polymerization of Individual Macrocyclic Poly(arylene thioether ketone)s under Dynamic Heating Conditions

Uncatalyzed, ring-opening polymerization of individual macrocyclic poly(arylene thioether ketone)s (1−4) and mixtures (5) under dynamic heating conditions has been demonstrated for the first time. High-molecular-weight, film-forming products were obtained after heating of the macrocycles up to 480 °C, with a heating rate of 10−20 °C /min. Depending on the macrocyclic structure and heat treatment conditions, the polymers obtained were amorphous or semicrystalline, soluble or slightly cross-linked. NMR analyses of the soluble polymers revealed their linear, highly regular structure. According to NMR, DSC, and TGA studies, the polymers obtained do not contain any residual macrocycles. The polymers with thio-p-arylene moieties in the main chain were thermally stabile. The catalyzed ring-opening polymerization of 5 carried out in diphenyl sulfone solution is also reported for comparison. Using quantum mechanical calculations of the ring opening of macrocycles, a reaction mechanism is suggested. Preparation of ...

Syntheses of Semicrystalline Aromatic Poly(thioether thioether ketone)s (PTTK and PTBTK) and Their Copolymers with Ether Analogues

One-pot polymerization between bis(N,N'-dimethyl-S-carbamate)s and activated dihalo compounds was extended to the synthesis of semicrystalline poly(arylene thioether)s as well as their copolymers. Aromatic poly(thioether thioether ketone) (PTTK) and poly(thioether biphenyl thioether ketone) (PTBTK) were synthesized from 4,4'-difluorobenzophenone and bis(N,N'-dimethyl-S-carbamate)s prepared from hydroquinone and 4,4'-biphenol via the Newman-Kwart rearrangement reaction, respectively. Random copolymers were prepared by copolymerization of 4,4'-difluorobenzophenone with a mixture of bis(N,N'-dimethyl-S-carbamate)s or with a bis(N,N'-dimethyl-S-carbamate) and hydroquinone or 4,4'-biphenol. The reactions were carried out in benzophenone solution in the presence of a mixture of Cs 2 CO 3 and CaCO 3 as the bases at polymerization temperatures ranging from 200 to 300 °C in order to keep the products in solution. All the polymers obtained were semicrystalline, as evidenced from the sharp melting points from the DSC scans for the polymers as prepared. However, the crystallization speeds for these polymers are very different depending on the compositions. The relationships between T g , T m , and structures are discussed. PTTK has a T g of 136 °C, T m of 304 °C, and an inherent viscosity of 0.32 dL/g in concentrated sulfuric acid, while PTBTK has a T g of 173 °C, T m of 351 °C, and an inherent viscosity of 0.46 dL/g.

Synthesis and Characterization of Amorphous Aromatic Poly(Thioether Ketone)s and Poly(Thioether Phenyl Phosphine Oxide)s

A series of aromatic poly(thioether ketone)s were synthesized from 4,4′-dimercaptodiphenyl ether (I) and 4,4′-dimercaptodiphenyl thioether (II), by reaction with a series of ketone-activated aromatic fluoro compounds (IIIa-e) in DMF in the presence of anhydrous K2CO3. Two poly(thioether phenyl phosphine oxide)s were also prepared from bis(4-fluorophenyl)phenyl phosphine oxide (IV). The aromatic polythioethers had inherent viscosities of 0.3–0.88 dL/g. All polymers were amorphous and soluble in such solvents as CHCl3, DMF, DMAc, NMP, and DMSO. The glass transition temperatures of these aromatic polythioethers were in the 154–251°C range, and the 5% weight loss temperatures in TGA were in the 420–541°C range in N2 and the 503–527°C range in air. Wide-angle x-ray diffraction data on selected polymers showed that the polymers were amorphous.

Rheological and chemorheological studies of cyclic aryl ether ketone and aryl ether thioether ketone oligomers containing the 1,2‐dibenzoylbenzene moiety

Rheological and chemorheological studies of cyclic aryl ether ketone and aryl ether thioether ketone oligomers containing the 1,2‐dibenzoylbenzene moiety

Rheological and chemorheological studies of cyclic aryl ether ketone and aryl ether thioether ketone oligomers containing the 1,2-dibenzoylbenzene moiety

The melt stability, shear rate, and temperature dependence of steady-state shear viscosity of molten cyclic aryl ether ketone and thioether ketone oligomers containing the 1,2-dibenzoylbenzene moiety have been investigated. The isothermal chemorheology of the ring-opening polymerization of cyclic oligomers 4 and 9 in the presence of a nucleophilic initiator was also conducted. The cyclic aryl ether ketone oligomers are thermally stable in the melt, and their melt viscosity is several orders of magnitude lower than their high molecular weight linear counterparts. At a given temperature, the steady-state shear viscosity of the molten cyclics initially undergoes shear thinning as the shear rate increases, and once the shear rate is above 10 s -1 , the molten cyclic oligomers behave like Newtonian fluids. For the amorphous cyclic oligomers studied, the steady-state shear viscosity at 100 s -1 at a given temperature only depends on their glass transition temperature. The cyclic aryl thioether ketone oligomers are thermally unstable in the melt and undergo ring-opening polymerization in the absence of an initiator to form high molecular weight linear polymers with a concomitant rapid increase in viscosity. The rate of change in viscosity increases with temperature and is promoted by the addition of a catalytic amount of elemental sulfur or a disulfide such as 2,2-dithiobis(benzothiazole). It is hypothesized that the ring-opening polymerization is initiated by the in situ generated thiyl radical(s) and proceeds via a free-radical route.

4-(Chloroacetyl)pyridinium Salt: A New Chromophoric and Solvatochromic Reagent of the Thiol Group

N-(4‘-chlorobenzyl)-4-(chloroacetyl)pyridinium chloride was prepared from the N-(4‘-chlorobenzyl)-4-acetylpyridinium chloride by chlorination with sulfuryl chloride. This chloro ketone had a half life of 150 min at pH 7.3 and reacted specifically with thiols. The reaction product with pentanethiol crystallized as an enol whose structure was determined by X-ray diffraction. The structure indicated conjugation of the sulfur with the pyridinium ring. In solution this enol was in equilibrium with the corresponding ketone and with the hydrate or the hemiketal according to the solvent. The enol was the major species in DMSO while in water the ketone and the hydrate were major. This solvent dependent equilibrium was reflected in the variation of the absorption coefficient at the maximum wavelength at around 400 nm according to the solvent. The absorption maximum wavelength of the thioether, a negative solvatochrome, depended on the solvent and showed a close to linear relationship with the polarity index of Snyder. The enolic hydroxyl group has a pKa of 7.4 and the α thioether ketone a pKa of 7.9. The chloro ketone is a useful reagent to explore the environment of reactive cysteine residue in proteins, giving information on the polarity of the environment by the position of the absorption maximum wavelength and the pKa of the enolic hydroxyl group.

Free-Radical Ring-Opening Polymerization of Macrocyclic Aryl Ether Thioether Ketone Oligomers

A facile free-radical ring-opening polymerization of macrocyclic aryl ether thioether ketone oligomers is described. Polymerization of the cyclic oligomers via a transthioetherification reaction to high molecular weight linear polymers is achieved both in the melt and in solution in the presence of a catalytic amount of elemental sulfur or 2,2‘-dithiobis(benzothiazole) (DTB). The free-radical nature of the polymerization reaction is indicated by electron paramagnetic resonance spectroscopy (EPR). The ring-opening polymerization reaction is unusual in that the molecular weight of the polymers obtained increases as the conversion of cyclic oligomers increases. The ring−chain equilibrium dramatically favors the formation of linear polymer, in which only low levels of cyclic materials are present after polymerization, even though the reaction is not enthalpically driven. The interchain equilibration is also a facile process during polymerization. This intermolecular transthioetherification is demonstrated by ...

Soluble, High Molecular Weight Ladder Polymers Possessing a Poly(phenylene sulfide) Backbone

A novel route to aromatic ladder-type polymers consisting of linearly annulated six-membered rings is presented. The synthetic sequence involves a polycondensation of dithioresorcinols and aromatic dichlorodiketones to high molecular weight poly(thioether ketone)s under basic conditions. The polymer-analogous ring closure to the desired ladder structures was accomplished by reducing the keto functionalities to the corresponding secondary polyalcohols followed by a Friedel-Crafts-analogous intramolecular cyclization. The course of the polycondensation and the subsequent polymer-analogous reaction steps was studied using model dimers. A uniform formation of completely linear annulated six-membered rings was found for 2-methylated dithioresorcinol as one of the starting compounds. The novel ladder polymers are attractive precursors for the synthesis of poly(arylene methide)s and polycations of the thioxanthylium type, which are isoelectronically related to the hitherto unknown poly[n]acene.

Syntheses and blend behavior of poly(phenylene thioether ether ketone)s (PTEKs) and poly(phenylene sulfone ether ketone)s (PSEKs)

A series of poly(phenylene thioether ketone)s (PTEKs) containing well defined oligo(phenylene sulfide) segments has been prepared via the nucleophilic aromatic substitution of bis(4-fluorobenzoyl)-terminated oligo(phenylene sulfide)s with various bisphenols. Amorphous and partially crystalline PTEKs with glass transition temperatures ranging from 110C to 184 C have been obtained. Poly(phenylene sulfone ether ketone)s (PSEKs), prepared by oxidizing PTEKs in a formic acid/hydrogen peroxide slurry. and PTEKs derived from 4,4'-bis(4-fiuorobenzoyl)diphenylsulfide and hydroquinone are miscible with Ultrason E2010P (PES). The thermal, dynamic mechanical and morphological properties ofPTEK/PES and PSEK/PES blends are reported.

Synthesis of aromatic poly(thioether ketone)

AbstractAromatic poly(thioether ketone)s were prepared by the direct polycondensation of aromatic dicarboxylic acids with aryl compounds containing ether or sulfide structures using phosphorus pentoxide/methanesulfonic acid (PPMA) as a condensing agent and solvent. Polycondensation proceeded smoothly and produced aromatic poly(thioether ketone)s with inherent viscosities up to 0.73 dL/g. The synthesis of substituted aryl ketones by the reaction of substituted benzoic acids with aryl compounds in PMMA was studied in detail to demonstrate the feasibility of the reaction for polymer formation. The thermogravimetry of the aromatic poly(thioether ketone)s showed a 10% weight loss in air and nitrogen at around 450 and 460°C, respectively. © 1992 John Wiley &amp; Sons, Inc.