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1.
High‐molecular‐weight poly(phthalazinone)s with very high glass‐transition temperatures (Tg's) were synthesized via a novel N–C coupling reaction. New bisphthalazinone monomers ( 7a–e ) were synthesized from 2‐(4‐chlorobenzoyl) phthalic acid in two steps. Poly(phthalazinone)s, having inherent viscosities in the range of 0.34–0.91 dL/g, were prepared by the reaction of the bis(phthalazinone) monomers with an activated aryl halide in a dipolar aprotic solvent in the presence of potassium carbonate. The poly(phthalazinone)s exhibited Tg's greater than 230 °C. polymer 8b synthesized from diphenyl biphenol and bis(4‐flurophenyl) sulfone demonstrated the highest Tg of 297 °C. Thermal stabilities of the poly(phthalazinone)s were determined by thermogravimetric analysis. All the poly(phthalazinone)s showed a similar pattern of decomposition with no weight loss below 450 °C in nitrogen. The temperatures of 5% weight loss were observed to be about 500 °C. The poly(phthalazinone)s containing 4,4′‐isopropylidenediphenol and 4,4′‐(hexafluoroisopropylidene) diphenol and diphenyl ether linkage were soluble in chlorinated solvents such as chloroform. Other poly‐(phthalazinone)s were soluble in dipolar aprotic solvents such as N,N′‐dimethylacetamide. The soluble poly(phthalazinone)s can be cast as flexible films from solution. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 2481–2490, 2003  相似文献   

2.
A series of novel phenolphthalein‐containing sulfonated poly(arylene ether phosphine oxide)s (sPAEPP) with various sulfonation degrees were synthesized by direct polycondensation. The structure of sPAEPP was confirmed by 1H‐NMR, 13C‐NMR, and IR spectroscopy. The high‐molecular weight of these polymers was determined by gel permeation chromatography (GPC). The transparent, tough, and flexible membranes could be achieved by solution casting. The macroscopic properties and microstructure of the obtained membranes were investigated in detail. The results showed that these sPAEPP membranes displayed excellent properties in terms of swelling, proton conductivity, and methanol permeability. For example, sPAEPP‐100 membrane exhibited an appropriate water uptake of 33.1%, a swelling ratio of only 11.7% (lower than 20.1% of Nafion 117), a proton conductivity of 0.11 S cm?1 (similar to that of Nafion 117) at 80 °C, and a methanol permeability of 4.82 × 10?7 cm2 s?1. Meanwhile, it also presented outstanding oxidative stability. Atomic force microscope (AFM) micrographs showed that the hydrophilic domains of the sPAEPP‐100 membrane formed connected and narrow ionic channels, which contributed to its high proton conductivity and good dimensional stability. As a result, sPAEPP‐100 membrane displays excellent application prospect for fuel cells. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019 , 57, 1097–1104  相似文献   

3.
A general method for the preparation of poly(aryl ether amide)s has been developed where the generation of an aryl ether linkage is the polymer-forming reaction. The amide linkage was found to be sufficiently electron-withdrawing to activate halo-substituents towards nucleophilic aromatic substitution analogous to conventional activating groups (i.e., sulfone, ketone, etc.). Model reactions demonstrated that the amide-activated displacement occurred with high selectivity in near quantitative yield and was judged suitable as a polymer-forming reaction. Appropriately fluoro-substituted amides were prepared and subjected to displacement polymerization with bisphenoxides in a N-methyl-2-pyrrolidone (NMP)/N-cyclohexyl-2-pyrrolidone (CHP) solvent mixture. High molecular weight polymers with glass transition temperatures in the 200–225°C range were obtained. © 1993 John Wiley & Sons, Inc.  相似文献   

4.
Poly(arylene ether)s containing N-arylenebenzimidazole groups were prepared by the aromatic nucleophilic displacement reaction of two new bis(hydroxyphenyl-N-arylenebenzimidazole)s with activated aromatic difluorides in sulfolane at 200°C in the presence of anhydrous potassium carbonate. The bis(hydroxyphenyl-N-arylenebenzimidazole)s were prepared from bis(o-aminoanilino) arylenes and phenyl-4-hydroxybenzoate. The polymers were soluble in N-methyl-2-pyrrolidinone and m-cresol and exhibited inherent viscosities from 0.37–0.86 dL/g and glass transition temperatures from 219–289°C. Thermogravimetric analyses showed 5% weight losses from 463–506°C in air and 467–522°C in nitrogen. Unoriented thin films exhibited tensile strengths, moduli, and break elongations at 23°C of 10.2–12.5 ksi, 318–365 ksi, and 4–7%, respectively, and at 177°C of 5.1–6.9 ksi, 256–296 ksi, and 1–5%, respectively. A 50 : 50 random copolymer prepared from 1,3-bis(4-fluorobenzoyl) benzene, 1,1'-(4,4'-biphenylene)-bis[2-(4-hydroxyphenyl)benzimidazole], and 5,5'-bis[2-(4-hydroxyphenyl)benzimidazole] exhibited higher moisture absorption and lower tensile properties than those predicted by a rule of mixtures relationship. The chemical, physical, and mechanical properties of these polymers are discussed. © 1993 John Wiley & Sons, Inc.?  相似文献   

5.
An unsymmetrical and noncoplanar heterocyclic dianhydride was synthesized from a bisphenol‐like phthalazinone, 4‐(4‐hydroxylphenyl)‐2,3‐phthalazin‐1‐one, and a series of novel poly(ether imide)s based on it, with intrinsic viscosities of 0.67–1.42 dL/g, were obtained by one‐step solution polymerization in m‐cresol at 200 °C for 20 h. The polymers were readily soluble in N‐methyl‐2‐pyrrolidinone and m‐cresol. The poly(ether imide)s derived from 4,4′‐oxydianiline and 4,4′‐methylenedianiline were also very soluble in chloroform, 1,1′,2,2′‐tetrachloroethane, and N,N‐dimethylacetamide. The glass‐transition temperatures were 289–326 °C, as determined by differential scanning calorimetry. All the degradation temperatures for 5% weight loss occurred above 482 °C in nitrogen. The tensile strength of thin films of some of the polymers varied from 103.1 to 121.4 MPa. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 6089–6097, 2004  相似文献   

6.
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 Tg/Tm ratios. © 1995 John Wiley & Sons, Inc.  相似文献   

7.
Novel poly(arylene ether)s with sulfonic acid containing pendent groups were successfully synthesized by the nucleophilic displacement of aromatic dihalides with bisphenols in an aprotic solvent in the presence of excess potassium carbonate followed by sulfonation with chlorosulfonic acid. The sulfonation took place only at the controlled positions on the phenyl rings due to the novel bisphenol structures designed. The sulfonic acid group containing polymers were very soluble in common organic solvents, such as dimethyl sulfoxide, N,N′‐dimethylacetamide, and dimethylformamide, but swelled only slightly in water. These sulfonic acid group containing polymers were readily cast into tough and smooth films from organic solvents. The synthesized polymers had high glass‐transition temperatures of 171.0–240.7 °C and high molecular weights of 15,600–33,000 Da. These films could potentially be used as proton‐exchange membranes for fuel cells. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 1779–1788, 2004  相似文献   

8.
以四烯丙基联苯二酚(TABP)、 双酚A和十氟联苯为原料, 通过室温缩聚制得含氟聚芳醚(FPAEs), 再将其与3-巯基丙酸进行加成, 制得羧基化含氟聚芳醚(CFPAEs). 通过改变TABP的投料量来调节产物的羧基含量. 以N-甲基吡咯烷酮(NMP)为溶剂, 将CFPAE涂层喷涂在马口铁上. 研究发现, CFPAE涂层具有优异的热稳定性和机械强度, 羧基的引入可显著提高含氟聚芳醚涂层的附着力. 当羧基含量为0.265 mmol/g时, 涂层的黏附力等级为0级, 铅笔硬度为6H, 不引起涂层破坏的最小轴棒直径为0.5 mm, 水接触角为103.9°. 此外, CFPAE涂层还具有优异的耐酸、 耐盐、 抗紫外老化和防腐蚀等性能. 研究结果表明, 羧基化是拓展含氟聚芳醚在特种氟碳涂料上应用的一种有效途径.  相似文献   

9.
Based on green chemistry, a simple and efficient direct synthesis of 4‐(4′‐hydroxyaryl)(2H)phthalazin‐1‐ones ( 2a–2f ) was developed in a two‐step reaction, in which the Friedel–Crafts acylation reaction of six phenols with phthalic anhydride was initially carried out and then followed by cyclization with hydrazine hydrate in good to excellent yields with high regioselectivity. A number of novel heterocyclic poly(arylene ether ketone)s were prepared conveniently from several unsymmetrical, twist, and noncoplanar phthalazinone‐containing monomers ( 2a–2f ) and an activated difluoro monomer via a N? C coupling reaction. It was very interesting that the obtained monomers and polymers exhibited diverse properties with the variation of the number and location of the substituted methyl groups. All these polymers had a high molecular weight with Mn and ηinh in the range of 44,960–169,000 Da and 0.38–0.79 dL/g, respectively. Actually, the obtained polymers displayed excellent thermal properties with Tg's ranging from 222 to 248 °C and 5% weight loss temperatures in nitrogen higher than 430 °C. Moreover, these polymers were readily soluble in common organic solvents, such as N‐methyl‐2‐pyrrolidone, chloroform, pyridine, and m‐cresol, and could be cast into flexible and colorless or nearly colorless films by spin‐coating or casting processes. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 1525–1535, 2007  相似文献   

10.
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 Tg. The comparison between techniques sheds some light on the distribution of free volume. © 1992 John Wiley & Sons, Inc.  相似文献   

11.
将合成的含氰基的双二氮杂萘酮单体与二氟芳香单体进行亲核取代反应, 制备了三种含氰基的新型聚芳醚, 并用TGA, DSC和GPC等分析手段对其综合性能进行表征. 结果表明, 含氰基聚芳醚具有优异的热稳定性(T5%>492 ℃)、较高的玻璃化转变温度(Tg=262~320 ℃)和良好的溶解性能, 易溶于氯代烷烃(如氯仿)和极性非质子性溶剂(如DMAc, DMF, NMP等).  相似文献   

12.
A novel aromatic diacid, 4, 4′-bis[2-(4-carboxyphenyl)phthalazin- 1-one-4-yl]-bisphenyl ether III, containing bisphthalazinone and ether linkages was prepared from nucleophilic substitution of p-chlorobenzonitrile with the bisphenol-like monomer I, followed by alkaline hydrolysis of the intermediate dinitrile II. A series of poly(ether amide)s containing bisphthalazinone and ether linkages derived from diacid III and aromatic diamines were synthesized by one-step solution condensation polymerization using triphenyl phosphite and pyridine as condensing agents. Moreover, the properties of poly(ether amide)s including thermal stability,solubility and crystallinity were also studied.  相似文献   

13.
Poly(arylene ether ketone)s (PAEKs) are the most commonly known high‐performance materials used for ion exchange and fuel cell membranes. Described here is the design of novel sulfonated PAEKs (SPAEKs) and nonsulfonated PAEKs containing crown ether units in the main chain, which can be used in sensing applications and ion‐selective membranes. To this end, 4,4′(5′)‐di(hydroxybenzo)‐18‐crown‐6 was synthesized and used as monomer in a step growth polymerization to form crown ether‐containing PAEKs and SPAEKs. The successful synthesis of PAEKs containing 18‐crown‐6 and sulfonate groups was confirmed by gel permeation chromatography, Fourier transform infrared spectroscopy, and nuclear magnetic resonance spectroscopy. Membranes are fabricated from the sulfonated polymers. Potassium ion transport properties of the SPAEK and crown ether‐containing SPAEK membranes are assessed by diffusion dialysis. Potassium ion diffusion in the crown ether‐containing SPAEK membranes is almost four times lower than K+ diffusion in the native polymer membranes, without crown ether. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 2786–2793  相似文献   

14.
Considerable research has been carried out to develop new condensation polymerscontai- mug heterocyclic units since many of these polymers possess outstandingstrength and moduli and are used predominantly as high temperature-resistant materialsand fibers. Phthalazinone and its derivatives have been known for almost a century'.Recently Hay et ap'3 first reported that phthalazinone and its derivatives were bisphenolIike monomers which can be polymerized with the activated aryl dihalide monomers …  相似文献   

15.
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 (Tg). The cured films also exhibited excellent thermal stability, transparency and hydrophobicity derived from fluorine atoms. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   

16.
A novel phosphonic acid containing bisphenol was successfully synthesized from phenolphthalein and m‐aminophenylphosphonic acid. A series of homo‐ and copoly‐(arylene ether)s containing phosphonic acid groups were prepared by solution nucleophilic polycondensation. These phosphonic acid containing polymers can readily be dissolved in common organic solvents, such as dimethyl sulfoxide, N‐methyl‐2‐pyrrolidinone, and N‐cyclohexylpyrrolidinone, and can be cast into tough and smooth films. The presence of phosphonic acid pendants in the poly‐(arylene ether)s was confirmed by NMR, matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry, and conductivity measurements. This is the first report on the attachment of phenylphosphonic acid groups as side chains to aromatic polyethers. These poly‐(arylene ether)s had very high glass‐transition temperatures ranging from 254 to >315 °C and high molecular weights. The conductivities of the synthesized polymers were analyzed by the Cole–Cole method, and they ranged from 10?5 to 10?6 Scm?1. The synthesized polymers also exhibited good solution processability. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 3218–3226, 2001  相似文献   

17.
新型的含芳香二腈基磺化聚芳醚腈酮的合成与表征   总被引:1,自引:0,他引:1  
通过Diels-Alder反应合成了一种新型的含芳香二腈基的双酚单体, 并利用此单体与活性二卤化物共聚合成了一系列高分子量的磺化聚芳醚腈酮聚合物. 聚合物的结构通过元素分析和核磁共振谱进行表征. 结果表明, 该聚合物具有优良的导质子率、尺寸和化学稳定性及良好的力学性能.  相似文献   

18.
A series of sterically‐encumbered, sulfonated, poly(arylene ether) copolymers were synthesized and their proton conductivity examined. The series was prepared by copolymerizing a novel monomer, 2″,3″,5″,6″‐tetraphenyl‐[1,1′:4',1″:4″,1″':4″',1″″‐quinquephenyl]‐4,4″″‐diol, with 4,4'‐difluorobenzophenone and bisphenol A. Subsequent sulfonation and solution casting provided membranes possessing ion exchange capacities of 1.9 to 2.7 mmol/g and excellent mechanical properties (Young's modulus, 0.2–1.2 GPa; tensile strength, 35–70 MPa; elongation at break, 62–231%). Water uptake ranged from 34 to 98 wt% at 80 °C/100% RH. Proton conductivities ranged between 0.24 to 16 mS/cm at 80 °C/60% RH, and 3 to 167 mS/cm at 80 °C/95% RH. TEM analysis of the polymers, in the dehydrated state, revealed isolated spherical aggregates of ions, which presumably coalesce when hydrated to provide highly conductive pathways. The strategy of using highly‐encumbered polymer frameworks for the design of mechanically‐robust and dimensionally‐stable proton conducting membranes is demonstrated. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 2579‐2587  相似文献   

19.
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.  相似文献   

20.
Summary: Poly(arylene ether amine)s were synthesized by a nucleophilic aromatic substitution polycondensation of bis[4‐fluoro‐3‐(trifluoromethyl)phenyl]amine with several bisphenols. Even though the monomer has an electron‐donating diphenylamine moiety, which normally deactivates a nucleophilic aromatic substitution (SNAr) reaction, the polymerization proceeded by a SNAr reaction to give high‐molecular‐weight polymers. The polymers show good solubility in common organic solvents and have Tgs in the range of 123 °C to 177 °C.

High‐molecular‐weight poly(arylene ether amine)s synthesized by a SNAr reaction with the monomer containing an electron‐donating diphenylamine moiety.  相似文献   


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