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1.
The interdiffusion and miscibility behavior of three different types of modified poly(arylether sulfone)s with deuterated poly(arylether sulfone) is studied by depth profiling using the nuclear reaction D(3He, α)p. The diffusion coefficients are found to be in the range of 10−15 and 10−14 cm2/s at 195°C. A random copolymer of poly(arylether sulfone) containing 4,4-bis-(4′-hydroxyphenyl)valeric acid units is only partially miscible with deuterated poly(arylether sulfone) when the comonomer content is 8.8 mol %, whereas blends with comonomer contents of 1.7 and 4.5 mol % are miscible as indicated by complete interdiffusion. The transition from miscibility to immiscibility is caused by repulsive interactions of copolymer segments and can be explained in terms of a mean-field theory of random copolymer blends. Also, poly(arylether sulfone)s grafted with 0.4 wt % maleic anhydride or having pyromellitic anhydride endgroups are miscible with deuterated poly(arylether sulfone)s. © 1997 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 35: 2083–2091, 1997  相似文献   

2.
High molecular-weight aromatic polyamides were obtained from 1,5- and 2,6-bis-(4′-carboxy-4-phenylenoxy-sulfonyl)naphthalene by direct polycondensation reaction in N-methyl-2-pyrrolidone with various aromatic diamines, using triphenyl phosphite and pyridine as condensing agents. The polymers were characterized by elemental analysis, thermogravimetric analysis, differential scanning calorimetry, and infrared analysis. The polyamides, obtained in quantitative yield, possessed inherent viscosities in the range 0.42–1.70 dL/g, glass transition temperatures between 245–310°C, and 10% weight loss temperatures in nitrogen and air above 435 and 424°C, respectively. Most of the polymers were soluble in aprotic solvents. The effect of the structure on properties, such as solubility, Tg, and thermal behavior, were also studied. © 1996 John Wiley & Sons, Inc.  相似文献   

3.
Two sulfonyl group-containing bis(ether anhydride)s, 4,4′-[sulfonylbis(1,4-phenylene)dioxy]diphthalic anhydride ( IV ) and 4,4′-[sulfonylbis(2,6-dimethyl-1,4-phenylene)dioxy]diphthalic anhydride (Me- IV ), were prepared in three steps starting from the nucleophilic nitrodisplacement reaction of the bisphenolate ions of 4,4′-sulfonyldiphenol and 4,4′-sulfonylbis(2,6-dimethylphenol) with 4-nitrophthalonitrile in N,N-dimethylformamide (DMF). High-molar-mass aromatic poly(ether sulfone imide)s were synthesized via a conventional two-stage procedure from the bis(ether anhydride)s and various aromatic diamines. The inherent viscosities of the intermediate poly(ether sulfone amic acid)s were in the ranges of 0.30–0.47 dL/g for those from IV and 0.64–1.34 dL/g for those from Me- IV. After thermal imidization, the resulting two series of poly(ether sulfone imide)s had inherent viscosities of 0.25–0.49 and 0.39–1.19 dL/g, respectively. Most of the polyimides showed distinct glass transitions on their differential scanning calorimetry (DSC) curves, and their glass transition temperatures (Tg) were recorded between 223–253 and 252–288°C, respectively. The results of thermogravimetry (TG) revealed that all the poly(ether sulfone imide)s showed no significant weight loss before 400°C. The methyl-substituted polymers showed higher Tg's but lower initial decomposition temperatures and less solubility compared to the corresponding unsubstituted polymers. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1649–1656, 1998  相似文献   

4.
Random copoly(p-phenylene sulfide sulfone/ketone)s (PPSS/K) are prepared in high yield by the polycondensation of sodium hydrosulfide (NaSH) with bis(4-chlorophenyl) sulfone (BCPS) and 4,4′-dichlorobenzophenone (DCBP). The polymerization is conducted between 200–220°C, depending on the composition of the copolymer, and in the presence of water without any detrimental effects to the molecular weight. The copolymers with sulfone/ketone mole ratios (S : K) > 25 : 75 are amorphous, while the copolymers with S : K ratios ≤ 25 : 75 are crystalline. These materials form tough, creaseable films and exhibit a linear increase in the glass transition temperature with increasing sulfone content. Sulfuric acid solutions of the copolymers are dark orange to red and display an increasing λmax in the uv-visible spectra as the S:K ratio of the copolymers decreases. © 1994 John Wiley & Sons, Inc.  相似文献   

5.
A series of new poly(aryl ether)s containing the pyrimidine moiety were prepared by a nucleophilic aromatic substitution polymerization reaction in an aprotic solvent (DMAc) in the presence of excess potassium carbonate. These polymers are high molecular weight, amorphous, and soluble in common solvents at room temperature. The polymers are easily cast from solution into flexible, colorless, and transparent films. They showed high glass transition temperatures ranging from 198 to 304°C by DSC analysis. The 5% weight losses by thermogravimetric analysis ranged from 478 to 580°C, indicating that these polymers are very thermostable in nitrogen and air. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1107–1110, 1998  相似文献   

6.
A series of isomeric bis(chlorophthalimide)s (BCPIs) were conveniently prepared from 3-chlorophthalic anhydride, 4-chlorophthalic anhydride, and mixtures thereof. Polymerization of BCPIs with bis(4-mercaptophenyl) sulfone (BMPS) proceeded smoothly in the presence of tributylamine, from which a class of isomeric poly(thioether ether sulfone imide)s (PTESIs) with inherent viscosities of 0.45-0.82 dL/g were obtained. The solubility, thermal stability, and mechanical properties of these polymers were characterized. Compared to the PTESIs derived from single BCPIs, i.e., 3,3′-, 3,4′-, or 4,4′-BCPIs, the PTESIs derived from mixed BCPIs showed better solubility and higher storage modulus. These PTESIs also demonstrated good thermal stability, giving only 5% weight loss at temperature of 490 °C in nitrogen atmosphere. The glass transition temperatures (Tgs) of these isomeric PTESIs were between 242 and 265 °C, and were increased with increasing of the ratio of 3-chlorophthalimide unit in the polymer backbone.  相似文献   

7.
A partially fluorinated and sulfonated poly(arylene sulfone) (SPSO) was successfully synthesized via nucleophilic polycondensation of 2,2‐bis(4‐fluorophenyl)hexafluoro‐propane with 4,4′‐thiobisbenzenethiol (TBBT). In a second step, the prepared poly(arylene sulfide) was oxidized to SPSO. The polymer was blended with the polybenzimidazole PBIOO® to obtain a mechanically stable membrane. This film was compared with other polymer blends, which were synthesized in our group in the last years. We were especially interested in the influence of different bridging groups such as ether, ketone, and sulfone groups. The affect on properties such as water uptake (WU), thermal stability, proton conductivity, and oxidative stability were analyzed in this work. Additionally, the blend membranes were characterized by gel permeation chromatography. The novel SPSO blend shows a high molecular weight, and its blend membrane with PBIOO has an excellent onset of ? SO3H group splitting‐off temperature (Tonset) of 334 °C. The proton conductivity amounts to 0.11 S cm?1, and the water uptake reaches 30%. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011  相似文献   

8.
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  相似文献   

9.
Novel methyl-substituted aromatic poly (ether sulfone)s and poly (ether ketone)s were synthesized from combinations of 3,3′,5,5′-tetramethylbipheny-4,4′-diol and 2,2′,3,3′,5,5′-hexamethylbiphenyl-4,4′-diol, and 4,4′-dichlorodiphenyl sulfone and 4,4′-difluorobenzo-phenone by nucleophilic aromatic substitution polycondensation. The polycondensations proceeded quantitatively in a N-methyl-2-pyrrolidone-toluene solvent system in the presence of anhydrous potassium carbonate to afford the polymers with inherent viscosities between 0.86 and 1.55 dL/g. The methyl-substituted poly (ether sulfone)s and poly (ether ketone)s showed good solubility in common organic solvents such as chloroform, tetrahydrofuran, pyridine, m-cresol, and N,N-dimethylacetamide. The tetramethyl- and hexamethyl-substituted aromatic polyethers had higher glass transition temperatures than the corresponding unsubstituted polymers, and did not decompose below 350°C in both air and nitrogen atmospheres. The films of the methyl-substituted poly (ether ketone)s became insoluble in chloroform by the irradiation of ultraviolet light, indicating the occurrence of photochemical crosslinking reactions. © 1994 John Wiley & Sons, Inc.  相似文献   

10.
Novel crosslinked sulfonated poly(ether sulfone)s (PESs) were prepared by thermal irradiation of the allyl-terminated telechelic sulfone polymers using a bisazide. The sulfonated polymers in different comonomer compositions were fully characterized by 1H NMR, and the crosslinked structure was also verified by FT-IR spectroscopic analyses. Having both the uniform distribution of the hydrophilic conductive sites and controlled hydrophobic nature by minimized crosslinking over the rigid rod poly(ether sulfone) backbone, the crosslinked polymer membrane (PES-60) offered excellent proton conductivity of 0.79 S cm−1 at 100 °C together with hydrolytic and oxidative stability. In addition, only 17% of methanol permeability of the Nafion® was observed for the crosslinked PES-60.  相似文献   

11.
The synthesis and characterization of a series of novel poly(aryl amide imide)s based on diphenyltrimellitic anhydride are described. The poly(aryl amide imide)s, having inherent viscosities of 0.39–1.43 dL/g in N-methyl-2-pyrrolidinone at 30°C, were prepared by polymerization with aromatic diamines in N,N-dimethylacetamide and subsequent chemical imidization. All the polymers were amorphous, readily soluble in aprotic polar solvents such as DMAC, NMP, dimethylsulfoxide, N,N-dimethylformamide, and m-cresol, and could be cast to form flexible and tough films. The glass transition temperatures were in the range of 284–366°C, and the temperatures for 5% weight loss in nitrogen were above 468°C. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 4541–4545, 1999  相似文献   

12.
Long‐chain branched poly(ether sulfone)s (PESs) were synthesized via self‐polycondensation of AB2 macromonomers. The linear PES oligomers synthesized by self‐polycondensation of 4‐chloro‐4′‐(4‐hydroxyphenyloxy)diphenyl sulfone were terminated with 4‐(3,5‐methoxyphenoxy)‐4′‐fluorodiphenyl sulfone to form AB2 macromonomer precursors. After conversion from methoxy to hydroxy groups, the AB2 macromonomers were self‐polycondensed to form long‐chain branched PESs. NMR measurements support the formation of the target macromonomers ( = 2930–67,800 (g mol?1); Mn = number average molecular weight) and long‐chain branched PESs. Gel permeation chromatography with multiangle light scattering measurements indicated the formation of high‐molecular‐weight (Mw) polymers over 104. The root‐mean‐square radius of gyration (Rg) suggests that the shape of the long‐chain branched PES synthesized from small AB2 macromonomers in solution is similar to that of hyperbranched polymers. Increasing resulted in larger Rg, suggesting a transition from hyperbranched to a linear‐like architecture in the resulting long‐chain branched PESs. Rheological measurements suggested the presence of strongly entangled chains in the long‐chain branched PES. Higher tensile modulus and smaller elongation at the break were observed in the tensile tests of the long‐chain branched PESs. It is assumed that the enhanced molecular entanglement points may act as physical crosslinks at room temperature. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 1825–1831  相似文献   

13.
The ability to achieve high molecular weight poly(ether ketone)s from the polycondensation of bis(aryl chloride)s with bis(phenolate)s has been consistently demonstrated. The polymerizations presented here help to delineate for specific bis(aryl chloride)/bisphenolate pairs the reaction conditions required to obtain high molecular weight polymers. Polycondensation of 1,3-bis(4-chlorobenzoyl)-5-tert-butylbenzene ( 6 ) and 2,2′-bis(4-chlorobenzoyl)-biphenyl ( 15 ) with various bisphenolates as well as of 2,2′-bis(4-hydroxyphenoxy)biphenyl ( 33 ) with 4,4′-dichlorobenzophenone ( 41 ) and 1,3-bis(4-chlorobenzoyl)benzene ( 43 ) were used as representative model systems to select reaction conditions that led to high molecular weight polymers. © 1995 John Wiley & Sons, Inc.  相似文献   

14.
The miscibility of blends of phenolphthalein poly(ether ether sulfone) (PES-C) and poly(ethylene oxide) (PEO) was established on the basis of the thermal analysis results. Differential scanning calorimetry (DSC) studies showed that the PES-C/PEO blends prepared by casting from N,N-dimethylformamide (DMF) possessed a single, composition-dependent glass transition temperature (Tg), and thus that PES-C and PEO are miscible in the amorphous state at all compositions at lower temperature. At higher temperature, the blends underwent phase separation, and the PES-C/PEO blend system was found to display a lower critical solution temperature (LCST) behavior. The phase separation process in the blends has also been investigated by using DSC. Annealed at high temperatures, the PES-C/PEO blends exhibited significant changes of thermal properties, such as the enthalpy of crystallization and fusion, temperatures of crystallization and melting, depending on blend composition when phase separation occurred. These changes reflect different characteristics of phase structure in the blends, and were taken as probes to determine phase boundary. From both the thermal analysis and optical microscopy, the phase diagram of the blend system was established. © 1997 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 35 : 1383–1392, 1997  相似文献   

15.
A novel series of poly(aryl ether sulfone ketone)s (PPESKs) containing phthalazinone and biphenyl moieties were prepared by two-step nucleophilic polycondensation reaction. The ^-Mw values of these copolymers were between 38,330 and 67,900. The glass transition temperatures (Tg) and 5% decomposition temperatures were ranged in 253-269 ℃ and 488-500 ℃, respectively, The structures of these copolymers were confirmed by FT-IR and ^1H NMR. Moreover, all the resultant copolymers were amorphous determined by wide angle X-ray diffraction (WAXD).  相似文献   

16.
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   

17.
Two series of novel amorphous poly(aryl ether phthalazine)s have been prepared via an intramolecular ring closure reaction of poly(aryl ether ketone)s (PAEKs) with hydrazine monohydrate. Fluorinated PAEKs, which display solubility in solvents incorporating a ketone functionality such as acetone or ethyl acetate, were converted to poly(aryl ether phthalazine)s to observe if these polymers would display similar solubility characteristics. The poly(aryl ether phthalazine)s have glass transition temperatures in the range of 278–320°C and show 5% weight loss points greater than 500°C in air and nitrogen atmospheres. The fluorinated poly(aryl ether phthalazine)s were not soluble in ketonic solvents. A series of poly(aryl ether phthalazine)s incorporating pendant 2-naphthalenyl moieties has been prepared in an attempt to produce amorphous, thermally stable polymers with high glass transition temperatures. The polymers have glass transition temperatures in the range of 287–334°C and show 5% weight loss points greater than 500°C in air and nitrogen atmospheres. Poly(aryl ether phthalazine)s undergo an exothermic reaction above the glass transition temperature. The major product of this reaction is a rearrangement of the phthalazine moieties to quiazoline moieties, however some crosslinking of the polymers occurs. Cured samples of the poly(aryl ether phthalazine)s show a small increase in the polymer Tg and are insoluble in all solvents tested. © 1996 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 34:1897–1905, 1996  相似文献   

18.
含萘结构聚芳醚砜的合成与表征   总被引:4,自引:0,他引:4  
聚芳醚砜;亚萘基;耐热性;溶解度;含萘结构聚芳醚砜的合成与表征  相似文献   

19.
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 Tgs and thermal stability as determined from DSC and TGA analysis. Poly(arylene sulfone)s have the highest Tgs 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  相似文献   

20.
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.  相似文献   

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