Effects of the structure on the properties of new poly(arylene ether sulfone)s containing naphthalene units

A series of new poly(arylene ether sulfone)s has been obtained by solution condensation polymerisation starting from 1,5- and 2,6-bis-(4-fluorosulfonyl)naphthalene with various aromatic dihydroxy compounds. The polymers, obtained in quantitative yields, possessed inherent viscosities in the range 0.28-0.68 dl g⁻¹, had good thermal stability (10% weight loss temperatures were above 405 and 420 °C respectively in nitrogen and air) and high glass transition temperatures (in the range 217-258 °C). They have been characterised by elemental and infrared analyses, GPC and wide-angle X-ray diffraction. The properties of these poly(arylene ether sulfone)s have been compared with those of the corresponding poly(arylene ether ketone)s.     

Controlled sulfonation of poly(arylene ether sulfone)s and poly(arylene ether ketone)s with different molecular structures for polymer electrolyte membranes

Poly(arylene ether sulfone) copolymers derived from 9,9-bis(4-hydroxyphenyl)fluorene, bisphenol S and 4,4′-difluorodiphenylsulfone and poly(arylene ether ketone) copolymers derived from 4-phenoxybiphenyl, diphenyl ether and isophthaloyl chloride were prepared as precursor polymers for sulfonation reaction in which sulfonic groups are introduced quantitatively into specified positions. Sulfonation reaction for these two series of copolymers by concentrated sulfuric acid was successfully carried out to give sulfonated polymers with controlled positions and degree of sulfonation. Thermal stability, moisture absorption and proton conductivity for these two series of copolymers were measured and the results were compared to those of perfluorosulfonic acid polymers.     

含氰基侧基聚芳醚砜的合成与表征

汉２，６－二卤苯甲腈、４，４′－二氯二苯砜、４，４′－二羟基二苯砜、间苯二酚、对苯二酚、酚酞及双酚Ａ为主要原料，合成了含不同结构单元和不同氰基含量的含氰基侧基的聚芳醚砜，并采用ＩＲ、＾１３ＣＮＭＲ等分析手段对其结构进行了表征，同时研究了结构单元和氰基含量对聚芳醚砜性能的影响。     

一类侧链型磺化聚芳醚砜质子交换膜的合成及表征

以4,4'-二氟二苯砜和N-溴代丁二酰亚胺为起始原料,经两步有机反应设计并合成了一种新型活性二氟砜单体:3,3'-双(苯氧基苯基)-4,4'-二氟二苯砜,并由该单体与4,4'-二氟二苯砜、4,4'-二羟基二苯甲酮经亲核缩聚合成了侧链型聚芳醚砜聚合物(PAES-xx).通过较温和的后磺化反应,制得了一系列磺化聚芳醚砜质子交换膜(SPAES-xx).对所制侧链型聚芳醚砜质子交换膜的结构和性能分别进行了表征分析.结果表明,该类质子交换膜具有适中的吸水率和较好的尺寸稳定性,80℃时最高质子传导率达0.16 S/cm.此外,该类质子交换膜还具有良好的热稳定性和机械性能,起始分解温度约为250℃;膜的拉伸强度为29.5~42.0MPa,拉伸模量为0.62~1.23 GPa,断裂伸长率在9.0%~31.9%.磺化膜优良的综合性能主要归因于侧链磺化结构的引入和相分离结构的形成.     

Poly(arylene ether)s,poly(arylene thioether)s,and poly(arylene sulfone)s derived from a dihydroxy(imidoarylene) monomer

Novel poly(arylene ether)s, poly(arylene thioether)s, and poly(arylene sulfone)s were synthesized from the dihydroxy(imidoarylene) monomer 1 . The syntheses of poly(arylene ether)s were carried out in DMAc in the presence of anhydrous K₂CO₃ by a nucleophilic substitution reaction between the bisphenol and activated difluoro compounds. Poly(arylene thioether)s were synthesized according to the recently discovered one-pot polymerization reaction between a bis(N,N′-dimethyl-S-carbamate) and activated difluoro compounds in the presence of a mixture of Cs₂CO₃ and CaCO₃. The bis(N,N′-dimethyl-S-carbamate) 3 was synthesized by the thermal rearrangement reaction of bis(N,N′-dimethylthiocarbamate) 2 , which was synthesized from 1 by a phase-transfer catalyzed reaction. The poly(arylene thioether)s were further oxidized to form poly(arylene sulfone)s, which would be very difficult, if not impossible, to synthesize by other methods. All of the polymers described have extremely high T_gs and thermal stability as determined from DSC and TGA analysis. Poly(arylene sulfone)s have the highest T_gs and they are in the range of 298–361°C. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1201–1208, 1998     

Co‐poly(aryl ether sulfone)s containing phthalimidine moiety in the main chain

Several new co‐poly(arylene ether sulfone)s have been prepared by the reaction of 4,4′‐fluorodiphenyl sulfone (FDS) with different bisphenols namely 4,4′‐isopropylidenediphenol (BPA), 4,4′‐hexafluoroisopropylidenediphenol (6F‐BPA), and N‐phenyl‐3,3‐bis(4‐hydroxyphenyl)phthalimidine(PA). The homo‐poly(arylene ether sulfone)s are named as 1a, 2a, and 3a. The copolymers namely 2b, 2c, 2d and 3b, 3c, 3d have been prepared, respectively, on reaction of FDS with BPA or 6F‐BPA using different molar ratios of PA such as 25, 50, and 75. The poly(aryl ether sulfone)s 1a containing PA unit in the main chain showed a very high glass transition temperature of 280°C and an outstanding thermal stability up to 510°C for 5% weight loss under synthetic air. Depending on the mole% of PA, the glass transition temperatures of the copolymers can be varied. The polymers were soluble in a wide range of organic solvents. Transparent thin films of these polymers exhibited tensile strengths upto 84 MPa and Young's modulus up to 3.16 GPa. The films of these polymers showed low water absorption of 0.24%. Copyright © 2009 John Wiley & Sons, Ltd.     

Poly(arylene ether sulfone)s containing pendant sulfonic acid groups as membrane materials for direct methanol fuel cells

A series of poly(arylene ether sulfone)s containing pendant sulfonic acid groups have been prepared by an aromatic substitution polymerization reaction using 4,4-difluorodiphenylsulfone, 6,7-dihydroxy-2-naphthalenesulfonate, and various hydroxyl terminated monomers in the presence of potassium carbonate. The synthesized sulfonated polymers have been characterized by nuclear magnetic resonance spectroscopy, Fourier transform infrared spectroscopy, gel permeation chromatography, ion exchange capacity, thermogravimetric analysis, and proton conductivity measurements. With a molecular weight of 50,000–59,000 g/mol and an ion exchange capacity of 1.17 meq./g, these polymers are thermally stable up to 250 °C. They are found to exhibit better performance at 65 and 80 °C in direct methanol fuel cells than Nafion 115 membrane despite lower proton conductivity due to a significantly lower methanol crossover.     

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.     

交联嵌段磺化聚芳醚砜质子交换膜的制备及性能

为提高磺化聚芳醚砜(SPAES)质子交换膜的质子传导率及稳定性, 制备了一系列交联嵌段SPAES质子交换膜(cbSPAES). 采用嵌段共聚方法, 在P₂O₅存在下, 利用磺酸基团与聚合物主链上活泼氢的脱水反应进行交联改性合成嵌段聚合物. 采用电化学阻抗谱技术测定了cbSPAES膜的质子传导率, 通过测试水中膜平面及厚度方向的尺寸变化率评价膜的尺寸稳定性, 通过加速老化试验评价膜的水解稳定性. 结果表明, 与未交联膜相比, cbSPAES膜的尺寸稳定性及水解稳定性明显提高; 在交联程度相同时, cbSPAES膜的吸水率和质子传导率随着磺化链段长度的增加呈上升的趋势. 如cbSPAES(30/10)-10膜在60 ℃水中的吸水率为65%, 平面方向和厚度方向的尺寸变化率分别为0.16和0.18, 质子传导率达到163 mS/cm.     

Sulfonated poly(arylene ether sulfone) ionomers containing fluorenyl groups for fuel cell applications

A series of sulfonated poly(arylene ether sulfone)s (SPEs) containing fluorenyl groups as bulky components were synthesized and characterized for fuel cell applications. Introduction of disodium 3,3′-disulfo-4,4′-difluorophenyl sulfone (SFPS) monomer gave ionomers with high acidity and accordingly high proton conductivity as well as high proton diffusion coefficient (D_σ) at low humidity. The membrane of SPE60 (where the number denotes mole percentage of the component containing sulfonic acid groups; IEC (ion exchange capacity) = 1.68 mequiv./g) exhibited high proton conductivity of 4.6 × 10⁻³ S/cm at 40% RH and 80 °C, which is one order of magnitude higher than that (6 × 10⁻⁴ S/cm) of our previous SPE (SPE-1, IEC = 1.58 mequiv./g). D_σ of SPE60 membrane was ca. 4 times higher than that of the SPE-1 membrane at low water volume fraction. SPE membranes showed good oxidative and hydrolytic stability as well as favorable thermal and mechanical properties. Small-angle X-ray scattering analyses showed that the phase separation of SPE membranes was much less developed than that of the perfluorinated Nafion membrane which accounts for lower hydrogen and oxygen permeability of the former membranes.     

含氟磺化双三蝶烯型聚芳醚砜质子交换膜的制备及性能

利用3,3,4,4-四氟二苯砜、十氟联苯、6F-双酚A及6,13-双三蝶烯二酚,通过亲核取代共聚及后磺化方法制备了2个系列不同磺化度的磺化双三蝶烯型聚芳醚砜,并通过氢核磁共振波谱(1H NMR)对其化学结构进行了表征.研究发现,所得磺化聚芳醚砜均表现出了优异的热稳定性.此类膜材料具有优良的机械性能、尺寸稳定性、氧化稳定性及高温低湿度条件下高的质子传导率.透射电子显微镜的结果表明,聚合物主链中大量氟原子的引入显著改善了聚合物的相分离结构,并且随着聚合物主链中氟含量的增加,亲水区域明显增大.这也是含氟磺化双三蝶烯型聚芳醚砜质子交换膜材料在高温低湿度条件下具有高质子传导率的主要原因.     

含(4-磷酸)苯侧基聚芳醚砜的合成及杂化

本文通过含溴聚芳醚砜合成可溶性含(4-磷酸)苯侧基聚芳醚砜, 并通过与磺酸功能化聚倍半硅氧烷杂化的方法, 制备了磷酸聚合物为基体的有机-无机杂化高性能质子交换膜材料.     

The degradation mechanism of sulfonated poly(arylene ether sulfone)s in an oxidative environment

The degradation of sulfonated aromatic hydrocarbons based polymer electrolyte membranes is an important issue for fuel cell stability. However, its mechanism is relatively unclear. We have conducted accelerated radical tests and degradation product analysis for various sulfonated poly(arylene ether sulfone) (SPES) compounds. We evaluated the chemical durability of SPES, and observed its degradation mechanism under oxidative attack by hydrogen peroxide. Various SPES compounds were synthesized from 4,4′-biphenol, 4,4′-dihydroxy diphenyl sulfone, and 4,4′-dihydroxy benzophenone comonomers, and their physical properties were evaluated. SPES copolymerized with 4,4′-dihydroxy diphenyl sulfone had a higher durability towards oxidative attack compared with the other compounds studied, and SPES copolymerized with 4,4′-dihydroxy benzophenone exhibited the lowest durability.     

Free volume in glassy poly(arylene ether ketone)s

Amorphous polyarylene ether ketones were examined in the glassy state by positron annihilation lifetime spectroscopy (PALS) and in the melt by standard rheological techniques. Specimens were well-characterized fractions of two isomeric structures. PALS clearly shows that the polymer with meta linkages in its backbone contains larger voids (> 0.25 nm radius). Thus despite their similar bulk densities, the two materials must pack very differently on a local scale. On the other hand, the free volumes inferred from the WLF treatment of melt viscosity data are practically identical in both materials ca. 4% at T_g. The comparison between techniques sheds some light on the distribution of free volume. © 1992 John Wiley & Sons, Inc.     

Synthesis,characterization, and thermal properties of novel arylene sulfone ether polyimides and polyamides

A new aromatic sulfone ether diamine was synthesized by nucleophilic aromatic substitution reaction of 5‐amino‐1‐naphthol with bis(4‐chlorophenyl) sulfone in the presence of potassium carbonate in a polar aprotic solvent. Polycondensation reactions of the obtained diamine with pyromellitic dianhydride (PMDA), benzophenonetetracarboxylic dianhydride (BTDA), and hexafluoroisopropylidene diphthalic anhydride (6FDA) resulted in preparation of thermally stable poly(sulfone ether imide)s. Poly(sulfone ether amide)s also were prepared by reaction of the diamine with terephthaloyl chloride (TPC) and isophthaloyl chloride (IPC). The prepared monomer and polymers were characterized by conventional methods. Physical and mechanical properties of polymers, including thermal stability, thermal behavior, solution viscosity, solubility behavior, and modulus, also were studied. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 1487–1492, 2000     

填充型具有微孔结构的磺化聚芳醚砜/聚醚砜复合质子交换膜的制备及性能

制备了基于磺化聚芳醚砜(SPAES)及聚醚砜(PES)的填充型复合质子交换膜, 研究了其吸水率、 尺寸变化、 热-机械特性、 质子电导率、 甲醇透过性及稳定性等性能. 通过浸入沉淀相转化法, 采用磺化度分别为30%(S30), 40%(S40)及50%(S50)的SPAES与PES制备了系列微孔型复合质子交换膜 Sx-y(x为SPAES的磺化度, y为SPAES的质量分数); 然后利用真空抽滤法在微孔中填充S50制备了相应的填充型复合质子交换膜Sx-y+F50. 结果表明, 由于微孔的引入及皮层结构的存在, Sx-y膜在低离子交换容量(IEC)条件下仍具有较高的电导率、 优良的机械强度、 优异的化学稳定性及较低的甲醇透过性. 经S50填充后, Sx-y+F50膜的IEC及电导率明显提升, 甲醇透过率大幅下降, 但机械强度及化学稳定性未见劣化. 其中S30-40+F50膜(IEC=0.69 mmol/g)的综合性能最佳, 其质子电导率在90 ℃水中达到50.4 mS/cm; 经140 ℃水处理24 h后失重率仅为8.2%, 质子电导率降低仅9%; 经过芬顿试剂(3% H₂O₂, 20 mg/L FeSO₄, 80 ℃, 1 h)处理后失重率仅为0.66%; 甲醇透过率仅为6.8×10^-8 cm²/s.     

Radiation degradation of poly(arylene ether ketone)s

The resistance of five poly(arylene ether ketone)s with related chemical structures to degradation by ionizing radiation has been studied by ESR spectroscopy and yields of volatile products. All of the polymers showed high resistance to radiation with low yields of radicals after irradiation in vacuum at 77 K (when up to 84% of the radicals were identified as radical anions) and much lower yields at 300 K. The yields of volatile products were much less than reported for poly(arylene sulfone)s [1, 2]. Methyl substitution on a main-chain aromatic ring decreased the radiation resistance, but methane only comprised 10% of the volatile products from the methyl-substituted polymers. A polymer containing an isopropylidene group in the main chain and a substituent aromatic carbonyl showed significantly decreased radiation resistance. Extremely low radical yields were obtained after irradiation in air at 300 K, contrary to many polymers. XPS analysis showed an increase in C–O bonds on the surface after irradiation in air.     

Synthesis and characterization of copoly(arylene sulfide)s

Copolymerizations of p-dichlorobenzene (DCB)/4-bromophenyl ether (BPE), DCB/4,4′-dibromobiphenyl (DBB), and DBB/BPE pairs with sodium sulfide under high temperature (270–290°C) utilizing N-methyl-2-pyrrolidinone (NMP) as solvent were carried out to give C(DCB/BPE), C(DCB/DBB), and C(DBB/BPE) copolymers, respectively. The reactivity of dihaloaromatic monomers toward thiolate anion in the polycondensation reaction followed the order DBB > DCB > BPE. The reactivity gap between DBB and DCB toward thiolate anion seemed to be smaller than that between BPE and DCB, resulting in both high yield and high molecular weight in the C(DCB/DBB) copolymers compared to C(DCB/BPE) copolymers. The copolymerization of DBB/BPE pair with sodium sulfide, which has larger reactivity gap than the DCB/DBB or DCB/BPE pair, gave mixtures of PBS and PPSE homopolymers especially in the range of 50–80 mol % BPE in the feed. The C(DCB/DBB) and C(DCB/BPE) copolymers, however, exhibited random copolymer character in all comonomer ratios in the feed as evidenced by copolymer composition and DSC data. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 2311–2317, 1999     

Synthesis and properties of multiblock copoly(arylene ether)s containing superacid groups for fuel cell membranes

A series of block copoly(arylene ether)s containing pendant superacid groups were synthesized, and their properties were investigated for fuel cell applications. Two series of telechelic oligomers, iodo‐substituted oligo(arylene ether ketone)s and oligo(arylene ether sulfone)s, were synthesized. The degree of oligomerization and the end groups were controlled by changing the feed ratio of the monomers. The nucleophilic substitution polymerization of the two oligomers provided iodo‐substituted precursor block copolymers. The iodo groups were converted to perfluorosulfonic acid groups via the Ullmann coupling reaction. The high degree of perfluorosulfonation (up to 83%) was achieved by optimizing the reaction conditions. Tough and bendable membranes were prepared by solution casting. The ionomer membranes exhibited characteristic hydrophilic/hydrophobic phase separation with large hydrophilic clusters (ca. 10 nm), which were different from that of our previous random copolymers with similar molecular structure. The block copolymer structure was found to be effective in improving the proton‐conducting behavior of the superacid‐modified poly(arylene ether) ionomer membranes without increasing the ion exchange capacity (IEC). The highest proton conductivity was 0.13 S/cm at 80 °C, 90% relative humidity, for the block copolymer ionomer membrane with IEC = 1.29 mequiv/g. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011