Synthesis of a new monomer for sulfonated poly(arylene ether sulfones)

Russian Chemical Bulletin - 4-({2,4-Bis[(4-chlorophenyl)sulfonyl]phenyl}thio)benzenesulfonic acid was synthesized based on the scheme suggested from the results of retrosynthetic analysis. This...     

Synthesis and characterization of sulfonated poly(acrylene ether sulfones)

Ionic groups incorporated into a polymer have a decided effect on its physical properties. A number of ionomers and polyelectrolytes have been widely applied. In particular, sulfonated bisphenol-A polysulfone (SPSF) has been used as a composite or single-component membrane for the desalination of water. In this article, the synthesis and physical characteristics of sulfonated polysulfone are addressed. A detailed synthesis route is provided and methods that yield determinable levels of sulfonation are described. These ion-containing polymers retain an excessive amount of residual salts, which, of course, are impurities to the system. Therefore, before any analyses were made the polymers were subjected to a thorough soxhlet extraction process with boiling water, which appeared to be quite effective. The degree of sulfonation was assessed by several methods such as ¹H NMR and FT-IR. A new ¹H NMR method was derived because the method cited in the literature proved to be too inconsistent for our work. The new ¹H NMR method used a quaternary ammonium counterion [N(CH₃)₄]. These methyl protons are easily measured and may be ratioed against the isopropylidene protons in the polymer backbone that act as an internal standard. Characterization of the physical properties of SPSF consisted of water uptake, differential scanning calorimetry (DSC), thermomechanical analysis (TMA), and solubility studies. Its physical appearance and mechanical behavior were improved by the solution procedure. Also addressed were the effects of different counterions (Na⁺ & Mg⁺⁺) with SPSFs of low levels of sulfonation. The variation in physical properties between the divalent and monovalent counterions is dramatic, especially when observed by TMA in the rubber plateau above the apparent glass temperature.     

Synthesis and characterization of poly(arylene ether imidazole)s

Poly(arylene ether imidazole)s were prepared by the aromatic nucleophilic displacement reaction of a bisphenol imidazole with activated aromatic dihalides. The polymers had glass transition temperatures ranging from 230 to 318°C and number-average molecular weights as high as 82,000 g/mol. Thermogravimetric analysis showed a 5% weight loss occurring ～ 400°C in air and ～ 500°C in nitrogen. Typical neat resin mechanical properties obtained at room temperature included tensile strength and tensile modulus of 14.2 and 407 ksi and fracture energy (G_lc) of 23 in. lb/in.² Titanium-to-titanium tensile shear strengths measured at 23 and 200°C were 4800 and 3000 psi, respectively. In addition, preliminary data were obtained on carbon fiber laminates. The chemistry, physical, and mechanical properties of these polymers are discussed.     

Synthesis and characterization of new fluorescent poly(arylene ether)s

The poly(arylene ether)s were prepared by the nucleophillic aromatic substitution polymerization of phenolphthalin and its derivatives with activated aromatic difluorides. The polymers had glass transition temperatures ranging from 210 to 240°C. Though the monomers have no fluorescence, the resulting polymers fluoresced a light green color in solid and solution states. The maximum excitation and emission wavelengths are 420 nm and 470 nm, respectively. In the polymer solutions, the fluorescence intensity decreased gradually, but the intensity was recovered by heating the polymer at 220°C for a few minutes. The fluorescent polymer had a stable radical. A model compound having the same repeating unit of the polymer was also prepared. The fluorescence properties of this model were almost the same as those of the polymers. © 1994 John Wiley & Sons, Inc.     

交联型聚芳醚砜两亲嵌段聚合物的合成与表征

首先分别合成了主链上含有查尔酮结构的疏水段和侧链上含有叔胺的亲水段,然后通过疏水段与亲水段的末端缩合反应合成了一系列光敏性聚芳醚砜两亲嵌段聚合物,其结构和热性能分别通过1 H NMR,FT-IR,UV-Vis光谱,TGA和万能力学试验机等进行表征测试.该两亲性嵌段聚合物具有良好的溶解性、热稳性、力学性能和光敏性,在紫外光谱322nm处有最大吸收峰,在常温下经紫外光照射,分子链之间发生[2+2]环加成反应,聚合物分子之间形成交联结构,最大交联度可达到64%.     

Synthesis and characterization of novel poly(arylene ether)s containing 1,3,4-oxadiazole units

Starting from some new 2,5-disubstituted-1,3,4-oxadiazole difluorides, synthesized by cyclocondensation of dihydrazides with 4-fluorobenzoic acid, novel poly(arylene ether)s were prepared by halo displacement polymerizations with bisphenol A in the presence of potassium carbonate. Model reactions demonstrated the unsuitableness for halo displacement reactions of the difluoride containing the SO₂ group. The synthesis and characterization of polymers are discussed and the thermal properties are compared with those of other polymers reported in literature.     

Synthesis and properties of poly(arylene ether phenyl-s-triazine)s

A series of new poly(arylene ether phenyl-s-triazine)s was prepared by the nucleophilic aromatic substitution polymerization of the potassium salt of bisphenols with 2,4-bis (halophenyl)-6-phenyl-s-triazine in N-methyl-2-pyrrolidone at elevated temperature. The polymers with inherent viscosities exceeding 0.5 were obtained after polymerization for 1 h using 2,4-bis(fluorophenyl)-6-phenyl-s-triazine as a monomer. The glass transition temperatures of the resulting polymers ranged from 200 to 260°C depending on the bisphenol used in the polymer synthesis. The poly(arylene ether phenyl-s-triazine)s demonstrated excellent thermal stabilities in excess of 490°C (5% weight loss in air). The isothermal TGA measurements (400°C under air or nitrogen atmosphere) revealed that the 4,4'-biphenol- and hydroquinone-based poly(arylene ether phenyl-s-triazine)s belong to the most superior class of heat resistant polymers, such as polyimide Kapton?. The mechanical properties of these polymers are also described. © 1994 John Wiley & Sons, Inc.     

Synthesis and characterization of multiblock copolymers based on hydrophilic disulfonated poly(arylene ether sulfone) and hydrophobic partially fluorinated poly(arylene ether ketone) for fuel cell applications

Sulfonated fluorinated multiblock copolymers based on high performance polymers were synthesized and evaluated for use as proton exchange membranes (PEMs). The multiblock copolymers consist of fully disulfonated poly(arylene ether sulfone) and partially fluorinated poly(arylene ether ketone) as hydrophilic and hydrophobic segments, respectively. Synthesis of the multiblock copolymers was achieved by a condensation coupling reaction between controlled molecular weight hydrophilic and hydrophobic oligomers. The coupling reaction could be conducted at relatively low temperatures (e.g., 105 °C) by utilizing highly reactive hexafluorobenzene (HFB) as a linkage group. The low coupling reaction temperature could prevent a possible trans‐etherification, which can randomize the hydrophilic‐hydrophobic sequences. Tough ductile membranes were prepared by solution casting and their membrane properties were evaluated. With similar ion exchange capacities (IECs), proton conductivity and water uptake were strongly influenced by the hydrophilic and hydrophobic block sequence lengths. Conductivity and water uptake increased with increasing block length by developing nanophase separated morphologies. Atomic force microscopy (AFM) and transmission electron microscopy (TEM) experiments revealed that the connectivity of the hydrophilic segments was enhanced by increasing the block length. The systematic synthesis and characterization of the copolymers are reported. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 214–222, 2010     

Synthesis and properties of poly(arylene ether sulfone)s and poly(arylene ether ketones) derived from 4,4″-dihydroxy-o-terphenyl

Novel poly(arylene ether)s with a rigid and zigzag 4,4″-o-terphenyldiyl structure, introduced into the polymer backbone were synthesized by nucleophilic displacement reaction of 4,4″-dihydroxy-o-terphenyl with several activated aromatic dihalides in virtually quantitative yields. The poly(arylene ether)s having high molecular weight show both good solubility in common organic solvents and high thermal stability up to 545°C. They are amorphous with glass transition temperatures of 160–200°C.     

Synthesis and characterization of multiblock partially fluorinated hydrophobic poly(arylene ether sulfone)‐hydrophilic disulfonated poly(arylene ether sulfone) copolymers for proton exchange membranes

Hydrophobic‐hydrophilic sequence multiblock copolymers, based on alternating segments of phenoxide terminated fully disulfonated poly(arylene ether sulfone) (BPS100) and fluorine‐terminated poly(arylene ether sulfone) (6FBPS0) were synthesized and evaluated for application as proton exchange membranes. By utilizing mild reaction conditions the ether–ether interchange reactions were minimized, preventing the randomization of the multiblock copolymers. Tough, ductile, transparent membranes were solution cast from the block copolymers and were characterized with regard to intrinsic viscosity, morphology, water uptake, and proton conductivity. The conductivity values of the 6FBPS0‐BPSH100 membranes were compared to Nafion 212 and a partially fluorinated sulfonated poly(arylene ether sulfone) random copolymer (6F40BP60). The nanophase separated morphology was confirmed by transmission electron microscopy and small angle X‐ray scattering, and enhanced proton conductivity at reduced relative humidity was observed with longer block lengths. © 2013 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013     

Synthesis and properties of poly(arylene ether imide ketone)s

Poly(arylene ether ketone)s containing imide units were prepared by the aromatic nucleophilic displacement reaction of the potassium salts of bisphenols with bis(4-fluorobenzoyl)phthalimides in N-methyl-2-pyrrolidone at elevated temperature. The polymers having inherent viscosities of 0.34–0.77 dL/g were obtained in 2 h. The polymers exhibited glass transition temperatures ranging from 216 to 268°C and decomposition temperatures (5% weight loss under air atmosphere) ranging from 450–570°C mainly depending on the bisphenols used in the polymer synthesis. The isothermal TGA measurements (400°C under air or nitrogen atmosphere) revealed that the 4,4'-biphenol- and hydroquinone-based poly(arylene ether ketone imide)s belong to a superior class of heat resistant polymers. The mechanical properties of these polymers are also described. © 1994 John Wiley & Sons, Inc.     

Synthesis and characterization of soluble,fluorescent poly(arylene ether)s,poly(arylene thioether)s,and poly(arylene sulfone)s containing 1,3,5‐triphenylbenzene segments

The bisphenol 4,4″‐dihydroxy‐5′‐phenyl‐m‐terphenyl ( 4 ), containing a 1,3,5‐triphenylbenzene moiety, was synthesized from a pyrylium salt obtained by the reaction of benzaldehyde with p‐methoxyacetophenone with boron trifluoride etherate as a condensing agent. Polymers were obtained from 4 by a nucleophilic displacement reaction with various activated difluoro monomers and with K₂CO₃ as a base. A series of new poly(arylene ether)s ( 8a – 8f ) were obtained that contained phenyl‐substituted m‐terphenyl segments in the polymer chain. Polymers with inherent viscosities of 0.41–0.99 dL/g were obtained in yields greater than 96%. The polymers were soluble in a variety of organic solvents, including nonpolar solvents such as toluene. Clear, transparent, and flexible films cast from CHCl₃ showed high glass‐transition temperatures (T_g = 198–270 °C) and had excellent thermal stability, as shown by temperatures of 5% weight loss greater than 500 °C. 4 was converted via N,N‐dimethyl‐O‐thiocarbamate into the masked dithiol 4,4″‐bis(N,N′‐dimethyl‐S‐thiocarbamate)‐5′‐phenyl‐m‐terphenyl and was polymerized with activated difluoro compounds in the presence of a mixture of Cs₂CO₃ and CaCO₃ as a base in diphenyl sulfone as a solvent. A series of new poly(arylene thioether)s ( 9a – 9e ) were obtained with T_g values similar to those of 8a – 8e . 9a – 9e were further oxidized into poly(arylene sulfone)s with T_g values 40–80 °C higher than those for 8a – 8e and 9a – 9e . These polymers also had good solubility in organic solvents. A sulfonic acid group was selectively introduced onto the pendent phenyl group of polymers 8a and 8f by reaction with chlorosulfonic acid. The polymers were soluble in dipolar aprotic solvents and formed films via casting from dimethylformamide. Polymers 8a – 8f , 11a , and 11f showed blue and red fluorescence under ultraviolet–visible light with emission maxima at 380–440 nm. © 2002 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 40: 496–510, 2002; DOI 10.1002/pola.10136     

Synthesis and properties of new crystalline poly(arylene ether nitriles)

Crystalline poly(arylene ether nitrile) could be prepared by the polycondensation of 2,6-dihalobenzonitrile with resorcinol at 200°C in N-methylpyrrolidone in the presence of sodium carbonate. A reaction temperature of at least 200°C was necessary to attain high molecular weight polymer. Spectral data indicated that the polymer had the structure of a poly(meta-phenylene ether) with pendent nitrile groups on every other phenylene unit. Despite this structure, the crystallinity and the crystallization rate of the polymer were greater than those of the corresponding polymer with a para-linked structure. The glass transition temperature and the melting temperature of the polymer were almost the same as those of poly(etheretherketone) (PEEK^TM). A series of other new poly(arylene ether nitriles) were also examined. The polymers derived from 4,4′-biphenol, dihydroxytetra-phenylmethane, dihydroxydiphenylsulfone, and 1,5-isoquinolinediol had high glass transition temperatures. The poly(arylene ether nitriles) exhibited excellent tensile strength compared with the corresponding ketone- or sulfone-containing polymers. Comparing the three different kinds of polymers containing the same bisphenol units, the order of glass transition temperature was found to be sulfone- > nitrile- > ketone-containing polymers, while the order of tensile strength was nitrile- > ketone- > sulfone-containing polymers. The excellent mechanical properties are attributable to dipole-dipole interactions of nitrile groups. © 1993 John Wiley & Sons, Inc.     

Synthesis and characterization of postsulfonated poly(arylene ether sulfone) diblock copolymers for proton exchange membranes

Sulfonated poly(arylene ether sulfone) diblock copolymers were studied through the postsulfonation process. Two kinds of hydrophobic oligomers with a molecular weight of 20 kDa were prepared in advance as block sequences and then coupled together to obtain diblock copolymers. One oligomer was synthesized from bis(4‐hydroxyphenyl) sulfone (BHPS) and 4,4′‐difluorodiphenyl sulfone (DFDPS), which was thought to be incapable of postsulfonation. The other oligomer was synthesized from hydroquinone (HQ) and 4,4′‐dichlorodiphenyl sulfone (DCDPS), which successfully proceeded to a hydrophilic sequence as a result of sulfonation onto the HQ moiety after the coupling reaction. Consequently, a diblock copolymer with high molecular weight was obtained; although its intrinsic viscosity was too low to form a tough membrane because of its high rigidity and high crystallinity. Therefore, the use of decafluorobiphenyl (10F) as a termination reagent was investigated with the aim of achieving higher coupling reactivity and a kinky property. As a result, a sulfonated diblock copolymer was successfully obtained with sufficient molecular weight and intrinsic viscosity to form the membrane, as well as with adequate thermal properties. It was observed that proton conductivity, water uptake, and the water diffusion coefficient increased with higher ion exchange capacity. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 700–712, 2009     

Synthesis and characterization of new poly(arylene ether)s containing heterocyclic units. II.

A series of new poly(arylene ether)s, containing naphthalene, pyridine, and quinoline units have been prepared by solution condensation polymerization. The synthesis involves nucleophilic displacement of aromatic dihalides with aromatic potassium bisphenates in an anhydrous dipolar aprotic solvent at elevated temperatures. The polymers, having inherent viscosity from 0.24 to 1.32 dL/g, were obtained in quantitative yield, have excellent thermal stability as shown by 10% weight loss temperatures in nitrogen and air (above 450 and 430°C, respectively) and high glass transition temperatures (in the range of 150–220°C). The introduction of quinoline moieties in the polymer backbone positively influences the thermal properties, such as high T_g/T_m ratios. © 1995 John Wiley & Sons, Inc.     

Synthesis and characterization of poly(arylene ether)s containing triphenylmethane moieties for proton exchange membrane

A series of poly(arylene ether)s containing triphenylmethane moiety were synthesized by the nucleophilic displacement of aromatic dihalides with bisphenols in an aprotic solvent in the presence of excess potassium carbonate. High molecular weight and fibrous polymers in white color can be readily afforded in short reaction time. The structures of the synthesized monomers and polymers were investigated by ¹H NMR and MS techniques. The sulfonation position of the synthesized polymer can be easily controlled and the water-up-take can be conveniently tailored by changing the amount of sulfonation agent. This sulfonated polymer 4b is soluble in polar organic solvents, such as NMP, DMAc, DMSO, DMF, ethylene glycol monomethyl ether, and can be readily cast into tough and smooth films from solutions. The sulfonated polymers can be potentially used as the proton-exchange membranes for fuel-cells.     

Synthesis of poly(arylene ether ketones) with terminal phenolic groups

Poly(arylene ether ketones) with preset molecular weights (reduced viscosity from 0. 2 to 0.82 dL g^–1) containing terminal phenolic groups were synthesized by the reactions of 4,4-difluorobenzophenone with bisphenol A or phenolphthalein in the presence of K₂CO₃ in N,N-dimethylacetamide. The influence of an excess of bisphenols on the molecular weights of the polymers obtained was studied. The structures of the polymers were confirmed by ¹H NMR spectroscopy. The molecular weight distributions of the polymers were determined.Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1958–1961, September, 2004.     

Synthesis of thermally crosslinkable fluorine‐containing poly(arylene ether ketone)s—II. Propargyl ether terminated poly(arylene ether ketone)s

Novel thermally crosslinkable fluorine‐containing poly(arylene ether ketone)s comprised of 2,3,5, 6‐tetrafluoro‐1,4‐phenylene moiety were synthesized by the termination of polymer chain ends with propargyl ether groups in order to improve solvent resistance. Crosslinking reaction occurred over 250°C through the formation of both chromen ring and polyene structure. This structure change brought about not only the outstanding solvent resistance but also the increase in glass transition temperature (T_g). The cured films also exhibited excellent thermal stability, transparency and hydrophobicity derived from fluorine atoms. Copyright © 2004 John Wiley & Sons, Ltd.     

Dynamic mechanical relaxation effects in some poly(arylene sulfones)

Poly-4,4′-oxydiphenylenesulfonyl and poly-4,4′-methylenediphenylenesulfonyl were synthesized by an electrophilic substitution polymerization of the arylene monosulfonyl chloride monomers. The glass-transition temperatures T_g of these polymers were determined by calorimetric and dynamic mechanical measurements, and the number-average molecular weights were determined by vapor-pressure osmometry. Both polymers were found to have the same T_g at equivalent molecular weight; the limiting value at high molecular weight is 238°C. Both polymers have two dynamic mechanical relaxation peaks at temperatures far below T_g. One is in the neighborhood of 0°C, and the other is at ?110°C. Plausible origins for these relaxations, and the absence of any near 0°C in poly(4,4′-isopropylidenediphenylene-co-4,4′-sulfonyldiphenylene dioxide), are discussed.