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1.
聚醚砜醚酮的合成与性能   总被引:1,自引:1,他引:1  
以4,4′-二羟基二苯砜和4,4′-二氟二苯酮为单体, 通过溶液缩聚合成了聚醚砜醚酮(PESEK), 其分子结构相当于聚醚砜(PES)与聚醚醚酮(PEEK)的交替共聚物. 在共聚物分子中, 存在砜基、醚基和酮基, 整个结构单元形成了大共轭体系, 聚合物属无定形聚合物, 玻璃化转变温度(Tg)为198 ℃, 介于PEEK和PES的Tg之间, 其热稳定性和加工性能优于PES, 而力学性能与PES接近.  相似文献   

2.
We have synthesized new poly(arylene ether sulfone) (PAES) and polydimethylsiloxane (PDMS) segmented block copolymers where the PAES segments contain 20–30% of 4,4′-dihydroxyterphenol (DHTP) and 70–80% of bisphenol A (BA) units. The tensile and thermal properties of these new polymeric materials were measured and were compared to those of existing bisphenol A PAES–PDMS segmented block copolymers (BA PAES-b-PDMS). Also, a high molecular weight BA–DHTP PAES random copolymer containing 80% BA and 20% DHTP was prepared and its properties were compared to Udel®, a commercial PAES based on BA. The BA–DHTP PAES random copolymer had a significantly higher modulus, 1800 MPa and a higher Tg, 196 °C when compared to Udel®. In the segmented block copolymer materials, increased modulus and tensile strain at break (elongation) were also found when DHTP was incorporated into the PAES segments.  相似文献   

3.
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.  相似文献   

4.
Random and block copolymers of poly (ether sulfone) (PES) and poly (ether ether sulfone) (PEES) were synthesized by the nucleophilic polycondensation of 4,4′‐dichlorodiphenyl sulfone (DCDPS) with 4,4′‐dihydroxydiphenyl sulfone (DHDPS) and hydroquinone (HQ). Chemical structures of these copolymers were characterized by 13C NMR. The monomer molar fraction, sequential distribution, and degree of randomness of the copolymers were determined through analyses of the resonances of quaternary carbons in the DCDPS unit. Experimental results show that the molar fractions of the comonomer determined by 13C NMR analyses are close to the charged values in the synthetic step. Moreover, these copolymers, which were prepared by different polymerization methods, revealed different number‐average sequential length and degree of randomness. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 1624–1630, 2005  相似文献   

5.
We present a series of novel poly(arylene ether sulfone) copolymers containing pendant oligoaniline groups. A novel monomer containing oligoaniline, 2,6‐difluorobenzoyl aniline tetramer (DFAT), was synthesized by reaction of 2,6‐difluorobenzoyl chloride and parent aniline tetramer and incorporated into the aforementioned copolymers via direct copolymerization with 4,4′‐dichlorodiphenyl sulfone (DCDPS), and 4,4′‐isopropylidene diphenol (BPA) using N,N′‐dimethylacetamide as solvent. The structures of these copolymers were confirmed by FTIR, 1H NMR, and GPC. Spectral analysis of the copolymers in different oxidation states was investigated via UV‐visible spectra. The copolymers exhibited outstanding thermal stability and good solubility in various organic solvents. Their electroactivity, explored with cyclic voltammetry, was found to increase as the content of oligoaniline in the polymer increased. The electric and dielectric properties of the copolymers were also studied in detail. The electrochromic performance of the copolymers was investigated by electrochromic photographs and transmittance spectra; the color of the copolymer thin films changes from grey (at 0.0 V), to green (at 0.4 V), to blue (at 0.6 V) and to pearl blue (at 1.0 V) and the maximum transmittance change (ΔT) at 700 nm is 42.6% (90.7% ? 48.1%). © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011  相似文献   

6.
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.  相似文献   

7.
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 (Dσ) 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). Dσ 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.  相似文献   

8.
Chloromethylated poly(phthalazinone ether sulfone ketone) (CMPPESK) was prepared from poly(phthalazinone ether sulfone ketone) (PPESK) using chloromethyl octyl ethers (CMOE) with lower toxicity as chloromethylated regent.CMPPESK was soluble in N-methyl-2-pyrrolidone (NMP),N,N-dimethylacetamide (DMAc) and chloroform.Quatemized poly(phthalazinone ether sulfone ketone) (QAPPESK) was prepared from CMPPESK by quaternization.QAPPESK had excellent solvent resistance, which was only partly soluble in sulfuric acid (98%) and swollen in N,N-dimethylformamide (DMF).The vanadium redox flow battery (V-RFB) using QAPPESK anion-exchange membrane had better performance with 88.3% of overall energy efficiency.  相似文献   

9.
Thin (60 μm) and thick (250 μm) samples of poly(ether ether ketone) were subjected to radiochemical ageing at 24 kGy h−1 dose rate for doses up to 30.7 MGy at 60 °C in air. FTIR spectrophotometry (hydroxyl and carbonyl build-up), ATR microscopy (oxidation profiles), ammonia gaseous treatment (determination of carbonyl nature), density, DSC (glass transition temperature, cold crystallization and melting point changes), and gel content measurements (crosslinking) were conducted for examination of polymer degradation. Thin samples were shown to undergo principally chain scission process whereas thick ones undergo mainly crosslinking. This difference can be attributed to the kinetic control of oxidation by oxygen diffusion. A mechanistic scheme was proposed from radiochemical yields estimations.  相似文献   

10.
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   

11.
New segmented aromatic poly(ether sulfone)-amide and poly(ether sulfone)-imide copolymers were synthesized by the chain extension of α,w-diamine-terminated poly(ether sulfone) oligomer with both aromatic dicarboxylic acid chlorides and tetracarboxylic dianhydrides, respectively. Crystallization of the poly(ether sulfone)unit was suppressed by the introduction of amide or imide linkage along the polymer backbone, giving amorphous copolymers that were +eadily soluble in various organic solvents. The copolymers had somewhat higher glass transition temperatures than the parent poly(ether sulfone). They afforded transparent and tough films by solution casting. © 1992 John Wiley & Sons, Inc.  相似文献   

12.
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   

13.
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.  相似文献   

14.
A series of α,ω-dihydroxy polyarylene sulfones (PAES) were synthesized comprising bisphenol A (PAES1, Mn=1800, 4900, and 9500 daltons), 4,4-biphenol (PAES2, Mn=4100 daltons), and hexafluorobisphenol A (PAES3, Mn=3300 daltons). These were reacted with α,ω-dibromo poly(vinylidene fluoride) (PVDF, Mn=1200 daltons) prepared by telomerization, to yield block copolymers possessing rigid and flexible segments. Block copolymers were characterized by FTIR, NMR, GPC, DSC, TGA and TEM. In several cases the block copolymers exhibited distinct thermal transitions, i.e. Tm and Tg for PVDF and PAES segments, respectively. Where observable, Tg of PAES domains in the block copolymers occurred at a temperature lower than the corresponding PAES homopolymer due to the flexible nature of the surrounding PVDF domains. Block copolymers exhibited a similar thermal stability to the corresponding PAES homopolymers but higher stability than the PVDF homopolymer, and much higher still than α,ω-dibromo PVDF. TEM analyses indicate that phase separation of PAES and PVDF domains occurs on the nanometer scale.  相似文献   

15.
Abstract

Hydrophilicity-controlled poly(arylene ether sulfone) copolymers with phenolphthalein-based carboxylic acid groups (PES-COOH-X) were synthesized via direct copolymerization by adjusting the feed molar ratio. The chemical structures of the obtained copolymers were confirmed by 1H nuclear magnetic resonance (NMR) spectroscopy. The copolymers showed good solubility in common aprotic solvents and exhibited excellent mechanical properties. The water contact angles of the obtained copolymers could be reduced by approximately 52% from 92.1° to 44.2° with increasing content of phenolphthalein-derived monomer, 2-[bis(4-hydroxyphenyl)methyl] benzoic acid (PPH-COOH), in the feed molar ratio. A series of PES-COOH-X membranes was prepared via a conventional immersion precipitation phase inversion method. The effects of the monomer feed molar ratio on the morphology, hydrophilicity, pure water flux, and water uptake of the prepared membranes were investigated. The results showed that the pure water flux of the PES-COOH-X membranes was significantly enhanced by almost a factor of two as compared to the pristine PES membrane. From the water contact angle data, it was identified that the hydrophilicity of the membranes was increased rapidly with increasing PPH-COOH content in the membranes. These hydrophilicity-controlled poly(arylene ether sulfone) copolymers may be considered as good candidates for separation membrane materials.  相似文献   

16.
The synthesis of novel phosphorus-nitrogen synergism aromatic poly(ether sulfone)s was carried out successfully by using phosphorus-containing and nitrogen-containing biphenol-like monomers, 1,1′-bis(4-hydroxyphenyl)-metheylene-bispheny-1-oxophosphine oxide (DOPO-PhOH) and 1,2-dihydro-4-(4-hydroxyphenyl)phthalazin-1(2H)-one (DHPZ), in the usual synthesis procedure. Polymers with sufficient molecular weights could be obtained. The structure of the phosphorus-nitrogen containing poly(ether sulfone)s was characterized by means of Fourier transform infrared spectra (FTIR) and nuclear magnetic resonance spectroscopy (1H NMR, 31P NMR). The influence of monomer ratio on their thermal stability was also investigated by adjusting the proportion of DOPO-PhOH/DHPZ (mol/mol) from 80/20 to 20/80. The molecular weight and glass-transition temperatures (Tg′s) of the polymers increased with increasing content of the DHPZ monomer. The high thermal stabilities were depended on the different proportion of diol type incorporated.  相似文献   

17.
A new monomer, 4,4′‐bis(4‐phenoxybenzoyl)diphenyl(BPOBDP), was synthesized via a two‐step synthetic procedure. A series of novel poly(ether sulfone ether ketone ketone)/poly(ether ketone diphenyl ketone ether ketone ketone) copolymers were prepared by electrophilic Friedel–Crafts solution copolycondensation of isophthaloyl chloride (IPC) with a mixture of 4,4′‐diphenoxydiphenylsulfone (DPODPS) and 4,4′‐bis(4‐phenoxybenzoyl)diphenyl (BPOBDP), in the presence of anhydrous aluminum chloride and N‐methylpyrrolidone (NMP) in 1,2‐dichloroethane (DCE). The copolymers with 10–50 mol% DPODPS are semicrystalline and have remarkably increased Tgs over commercially available PEEK and PEKK. The copolymers with 40–50 mol% DPODPS had not only high Tgs of 170–172°C, but also moderate Tms of 326–333°C, which are extremely suitable for melt processing. These copolymers have tensile strengths of 96.5–108.1 MPa, Young's moduli of 1.98–3.05 GPa, and elongations at break of 13–26% and exhibit excellent thermal stability and good resistance to acidity, alkali, and common organic solvents. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

18.
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.  相似文献   

19.
The properties of diglycidyl ether of bisphenol-A epoxy resin toughened with poly(ether sulfone ether ketone) (PESEK) and poly(ether sulfone) (PES) polymers were investigated. PESEK was synthesised by the nucleophilic substitution reaction of 4,4’-difluorobenzophenone with dihydroxydiphenylsulfone using sulfolane as solvent and potassium carbonate as catalyst at 230 °C. The T g–composition behaviour of the homogeneous epoxy resin/PESEK blend was modelled using Fox, Gordon–Taylor and Kelley–Bueche equations. A single relaxation near the glass transition of epoxy resin was observed in all the blend systems. From dynamic mechanical analysis, the crosslink density of the blends was found to decrease with increase in the thermoplastic concentration. The storage modulus of the epoxy/PESEK blends was lower than that of neat resin, whilst it is higher for epoxy/PES blends up to glass transition temperature, thereafter it decreases. Scanning electron microscopic studies of the blends revealed a homogeneous morphology. The homogeneity of the blends was attributed to the similarity in chemical structure of the modifier and the cured epoxy network and due to the H-bonding interactions between the blend components. The fracture toughness of epoxy resin increased on blending with PESEK and PES. The increase in fracture toughness was due to the increase in ductility of the matrix. The thermal stability of the blends was comparable to that of neat epoxy resin.  相似文献   

20.
A novel type of crosslinkable poly(aryl ether sulfone)(PAES) bearing an allyl pendant(PES-OAllyl) was synthesized by a grafting reaction of hydrophenyl-containing PAES(PES-OH) and allyl bromide. PES-OH was prepared by a demethylation reaction of a methoxyphenylated PAES(PES-OCH3) in the presence of pyridine/hydrochlo- ride. The PES-OCH3 was synthesized by an aromatic nucleophilic substitution of bis(4-chlorophenyl)sulfone and (p-methoxy)phenylhydroquinone. Both DSC and solubility investigation were used to ...  相似文献   

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