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1.
聚醚醚酮(PEEK)是一种性能优异的工程塑料。笔者简单地介绍了聚醚醚酮的特性,对近年来磺化聚醚醚酮的制备、SPEEK的性能及应用做了比较全面的归纳,并对磺化聚醚醚酮未来的发展前景进行了展望。  相似文献   

2.
用浓硫酸磺化对苯二酚型聚芳醚酮(PAEK-H)制备了磺化聚芳醚酮(SPAEK-H),采用核磁共振、红外光谱和热失重对SPAEK-H的结构进行了表征,结果表明,采用直接磺化法成功地将磺酸基团引入到了PAEK-H分子链中。对其离子交换容量和磺化度进行了计算,并对SPAEK—H进行了力学性能测试,表明SPAEK-H具有较高的离子交换容量,具备一定的力学性能,较商用的Nation膜拉伸强度和弹性模量都有所提升。  相似文献   

3.
Water‐soluble sulfonated acetone–formaldehyde (SAF) resins were synthesized by the reaction among acetone, formaldehyde, and sodium bisulfite. The factors affecting the properties of SAF resins and optimum conditions of preparation were investigated. The SAF resins prepared under proper conditions have good water solubility and high performance as a superplasticizer used in concrete. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 91: 3248–3250, 2004  相似文献   

4.
Synthesis and properties of novel side-chain-type sulfonated polyimides   总被引:1,自引:0,他引:1  
A series of side-chain-type sulfonated polyimides (SPIs) were synthesized from 4,4′-ketone dinaphthalene-1,1′,8,8′-tetracarboxylic dianhydride (KDNTDA), 2,2′-(4-sulfophenoxy) benzidine, and nonsulfonated diamines. The SPIs showed anisotropic membrane swelling in water with 2–4 times larger swelling in thickness direction than that in plane one, being much different from SPIs derived from 1,4,5,8-naphthalenetetracarboxylic dianhydride. They exhibited good solubility in dimethyl sulfoxide and 1-methyl-2-pyrrolidone even in proton form, which is favorable for processing in fuel cell applications. KDNTDA-based SPIs displayed good mechanical properties with reduced viscosities ranged from 1.1 to 2.4 dl g−1 at 35 °C in triethylamine salt form. They also showed reasonably high proton conductivity and thermal stability.  相似文献   

5.
Poly(2,6‐dimethyl‐1,4‐phenylene oxide) (PPO) is a chemically resistant polymer and, therefore, an attractive material for the formation of membranes. However, membranes of unmodified PPO prepared by an immersion precipitation possess very low hydraulic permeabilities at the filtration processes. The membranes with higher hydraulic permeabilities can be prepared from sulfonated PPO and/or from blends of unsulfonated PPO and sulfonated PPO. In conclusion, the mechanism of the formation of membranes from blends of unsulfonated PPO and sulfonated PPO is suggested. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 73: 161–167, 1999  相似文献   

6.
A series of new cholesteric liquid‐crystalline polysiloxanes ( P1 – P5 ) derived from menthyl groups were synthesized. The chemical structures of the monomers and polymers were characterized with Fourier transform infrared, 1H‐NMR, 13C‐NMR, and elemental analyses. The mesomorphic properties and thermal behavior were investigated with differential scanning calorimetry, polarizing optical microscopy, thermogravimetric analysis, and X‐ray diffraction measurements. The influence of the polymer structure on the thermal behavior was discussed. The monomer diosgeninyl 4‐allyloxybenzoate exhibited a typical cholesteric oily‐streak texture and a focal‐conic texture. Polymers P1 – P5 showed thermotropic liquid‐crystalline properties. P1 displayed a smectic fan‐shaped texture, P2 – P5 showed a cholesteric Grandjean texture, and P6 and P7 did not show mesomorphic properties. The experimental results demonstrated that the glass‐transition temperature and the clearing temperature decreased, and the mesomorphic properties weakened with an increasing concentration of menthyl units. Moreover, P1 – P5 exhibited wide mesophase temperature ranges and high thermal stability. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102:5559–5565, 2006  相似文献   

7.
Novel bisphenol A‐based sulfonated poly(arylene ether sulfone) (bi A‐SPAES) copolymers were successfully synthesized via direct copolymerization of disodium 3,3′‐disulfonate‐4,4′‐dichlorodiphenylsulfone, 4,4′‐dichlorodiphenylsulfone, and bisphenol A. The copolymer structure was confirmed by Fourier transform infrared spectra and 1H NMR analysis. The series of sulfonated copolymers based membranes were prepared and evaluated for proton exchange membranes (PEM). The membranes showed good thermal stability and mechanical property. Transmission electron microscopy was used to obtain the microstructures of the synthesized polymers. The membranes exhibit increased water uptake from 8% to 66%, ion exchange capacities from 0.41 to 2.18 meq/g and proton conductivities (25°C) from 0.012 to 0.102 S/cm with the degree of sulfonation increasing. The proton conductivities of bi A‐SPAES‐6 membrane (0.10–0.15 S/cm) with high‐sulfonated degree are higher than that of Nafion 117 membrane (0.095–0.117 S/cm) at all temperatures (20–100°C). Especially, the methanol diffusion coefficients of membranes (1.7 × 10?8 cm2/s–8.5 × 10?7 cm2/s) are much lower than that of Nafion 117 membrane (2.1 × 10?6 cm2/s). The new synthesized copolymer was therefore proposed as a candidate of material for PEM in direct methanol fuel cell. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   

8.
Because of their unique structures and properties, π-conjugated polymers have attracted the attention of scientists and engineers. The authors have studied the synthesis of two kinds of π-conjugated poly(aromatic acetylene)s, i.e. poly(arylacetylene)s and poly(aryleneethynylene)s with the aim of obtaining new polymers having novel functions or higher performances. This review mainly concerns the authors' results, as follows: first, we describe the synthesis and properties of achiral poly(arylacetylene)s, containing trimethylsilyl groups, oligodimethylsiloxanyl groups, dendritic groups, and glavinoxyl groups, for application as oxygen permselective membrane materials. Their self-membrane-forming abilities and high oxygen permeabilities are presented. Second, the synthesis by asymmetric-induced polymerization of chiral poly(arylacetylene)s having both a main-chain chirality and chiral pendant groups and their application as optical resolution membranes are described. Third, two new synthetic methods for preparing chiral helical poly(phenylacetylene)s without the coexistence of any other chiral moieties are presented. One is helix-sense-selective addition polymerization and the other is in situ removal of chiral pendant groups from membranes of poly(arylacetylene)s that also contain a main-chain chirality. The chiral helical poly(arylacetylene)s were tested as optical resolution membranes. The chiral and achiral poly(arylacetylene)s were synthesized by addition polymerization using metathesis catalysts or rhodium complexes. Finally, the synthesis of regiospecific poly(aryleneethynylene)s bearing stable radicals by the polycondensation of bromoethynylanthracene derivatives using a Pd(0) complex is described. The magnetization and the static magnetic susceptibility of the polyradicals are explained.  相似文献   

9.
The viscosity and retention of several copolymers of acrylamide (AM) with sodium salt of 2‐acrylamido‐2‐methylpropane sulfonic acid (PAMS), and also hydrolyzed polyacrylamide (HPAM) have been studied under aerobic condition with and without the sacrificial agent, isobutyl alcohol (IBA) added at a temperature of 80°C. Parallel experiments have been performed in synthetic seawater (SSW) and 5 wt % NaCl. The viscosity at high temperature has been studied as a function of aging time, shear rate, sulfonation degree, molecular weight, and concentration of IBA. The retention in porous medium for sulfonated polyacrylamide polymers was measured in core floods using outcrop Berea sandstone. For the studied polymer sacrificial agent may protect polymer structure at high temperature. Higher sacrificial agent concentration gives better thermal stability in both 5 wt % NaCl and SSW solvents. Sulfonation degree also has a direct effect on thermal stability, i.e., higher sulfonation degree lead to better thermal stability in terms of viscosity. By increasing temperature, less relative reduction in polymer solution viscosity was observed for the polymer with lower molecular weight. The presence of divalent ions at high temperature leads to strong reduction of HPAM polymer solution viscosity, but the viscosity is better maintained for PAMS copolymer solution at high temperature. The precipitation of HPAM first occurred after 3 months at 80°C and for PAMS copolymer with lowest sulfonation degree precipitation started after 7 months. For the studied polymers the retention was found to be relatively independent of temperature and compared to HPAM a much lower retention is observed for the sulfonated copolymers. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   

10.
Sulfonated multiblock copolynaphthalimides (co-SPIs) with block length of 5-20 were prepared by a two-pot polymerization method from 1,4,5,8-naphthalenetetracarboxylic dianhydride, sulfonated diamines of 2,2′-bis(4-sulfophenoxy)benzidine (BSPOB) and 4,4′-bis(4-aminophenoxy)biphenyl-3,3′-disulfonic acid (BAPBDS) and nonsulfonated diamines. The scanning transmission electron microscopy showed that the BSPOB-based multiblock co-SPI membranes had well-defined microphase-separated structure where the hydrophilic and hydrophobic layer-like domains were oriented in the plane direction of membrane. On the other hand, the BAPBDS-based multiblock co-SPIs and all the random co-SPIs showed the homogeneous morphology. The water uptake, anisotropic membrane swelling, anisotropic proton conductivity and polymer electrolyte fuel cell (PEFC) performance were investigated for the multiblock and random co-SPIs. The results demonstrated strong effects of the membrane morphology on these properties. The BSPOB-based multiblock co-SPI membranes exhibited the larger through-plane swelling and the lower through-plane conductivity than the random ones, and as a result exhibited the lower PEFC performances. This study gives good understanding of the morphology-property relationship in novel block architectures' design.  相似文献   

11.
Kangcheng Chen 《Polymer》2009,50(2):510-4951
A novel sulfonated diamine bearing sulfophenyl pendant groups, namely, 4,4′-bis (4-aminophenoxy)-3,3′-bis(4-sulfophenyl) biphenyl and a series of sulfonated polyimides (SPIs) based on it were successfully synthesized. The SPIs had high viscosity and gave tough, flexible and transparent membranes. The SPI membranes showed anisotropic membrane swelling in water with 2.5-4 times larger swelling in thickness direction than in plane one. They displayed reasonably high proton conductivity. For example, the conductivities for the SPI with an ion exchange capacity of 1.80 mequiv/g were 104 and 7.3 mS/cm in water and 50% RH, respectively, at 60 °C. They maintained high mechanical strength and proton conductivity even after aging in water at 130 °C for 500 h, showing the high water stability comparable to the best SPI reported so far. In polymer electrolyte fuel cells (PEFCs) operated at 90 °C and 50% RH, they showed fairly high cell performances and have high potential for PEFC applications.  相似文献   

12.
A series of amorphous fluoro‐polyetherimides based on 2,2′‐bis(3,4‐dicarboxyphenyl) hexafluropropane dianhydride (6FDA) and di‐ether‐containing diamines 4,4′‐bis(3‐aminophenoxy)diphenyl sulfone (m‐SED), 4,4′‐bis(4‐aminophenoxy)diphenyl sulfone (p‐SED), 4,4′‐bis(4‐aminophenoxy)diphenyl propane (BPADE) were synthesized. These melt processable polyetherimide polymers from p‐SED and BPADE showed excellent electrical properties. The dielectric constants, 2.74 and 2.65 at 10 MHz respectively, are lower than commercially available polyetherimide ULTEM® 1000, and polyimide Kapton® H films. In addition, we found that trifluoromethyl groups‐containing polyimides not only show extraordinary electrical properties, but they also exhibit excellent long‐term thermo‐oxidative stability and reduced water absorption relative to non‐fluorinated polyimides. The weight retention of these fluoro‐polyetherimides at 315°C for 300 h in air varies from 93% to 98%. Whereas, their moisture absorption at 100 RH at 50°C was in the range of 0.3% to 1.05%, which is much lower than those of Ultem 1000 and Kapton H. In the case of fluoro‐polyetherimides from p‐SED and m‐SED (para and meta isomers) diamines with ‘ether’ and sulfonyl (‐SO2‐) spacer groups, the d‐spacing and Tg values decreased from 4.72Å to 4.56Å and 293°C to 244°C respectively. Similarly, the transparency of these polymer films (in the range of 80% to 90%) at 500 nm solar wavelength was higher than Ultem 1000 and Kapton H.  相似文献   

13.
A novel polymer (poly[2,2'‐(4,4'‐bithiazolylene)][N‐(2‐ethylhexyl)‐3,6‐carbazylene] (PBTCA) was first synthesized from 2,2′‐diamino‐4,4′‐bithiazole and N‐(2‐ethylhexyl)‐3,6‐diformylcarbazole. The structure of the polymer was determined with IR and 1H‐NMR spectroscopy. The PBTCA–Nd3+ complex was prepared via the mixing of neodymium trichloride hexahydrate and PBTCA in dimethyl sulfoxide under a nitrogen atmosphere. The magnetic behaviors of the Nd3+ complex of a poly(Schiff base) were measured as a function of the magnetic field strength (0–50 kOe) at 4 K and as a function of the temperature (4–300 K). The results show that PBTCA–Nd3+ is a ferromagnet when the temperature is below 15 K, and above that, it is a diamagnet. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 443–446, 2006  相似文献   

14.
A series of novel composite methanol‐blocking polymer electrolyte membranes based on sulfonated polyimide (SPI) and aminopropyltriethoxysilane (APTES) doping with sulfonated mesoporous silica (S‐mSiO2) were prepared by the casting procedure. The microstructure and properties of the resulting hybrid membranes were extensively characterized. The crosslinking networks of amino silica phase together with sulfonated mesoporous silica improved the thermal stability of the hybrid membranes to a certain extent in the second decomposition temperature (250–400°C). The composite membranes doping with sulfonated mesoporous silica (SPI/APTES/S‐mSiO2) displayed superior comprehensive performance to the SPI and SPI/APTES membranes, in which the homogeneously embedded S‐mSiO2 provided new pathways for proton conduction, rendered more tortuous pathways as well as greater resistance for methanol crossover. The hybrid membrane with 3 wt % S‐mSiO2 into SPI/APTES‐4 (SPI/A‐4) exhibited the methanol permeability of 4.68 × 10?6 cm2 s?1at 25°C and proton conductivity of 0.184 S cm?1 at 80°C and 100%RH, while SPI/A‐4 membrane had the methanol permeability of 5.16 × 10?6 cm2 s?1 at 25°C and proton conductivity of 0.172 S cm?1 at 80°C and 100%RH and Nafion 117 exhibited the values of 8.80 × 10?6 cm2 s?1 and 0.176 S cm?1 in the same test conditions, respectively. The hybrid membranes were stable up to about 80°C and demonstrated a higher ratio of proton conductivity to methanol permeability than that of Nafion117. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   

15.
Four series of novel fully aromatic thermotropic liquid crystalline high molecular weight poly(amide-esters were prepared by direct polycondensation from terephthalic acid (TPA) and 2,6-naphthalene dicarboxlic acid with various aromatic diols and diamines in the presence of diphenyl chlorophosphate (DPCP), LiCl, and pyridine. The structures and thermal properties of the synthesized poly(amide-ester) s were examined by FTIR spectrum, wide angle X-ray diffraction (WAXD), differential scanning calorimetry (DSC), thermal optical polarized microscope and thermogravimetric analysis (TGA). The effects of the amounts and kinds of the aromatic diols and diamines (bisphenyl units, naphthalene and (un)substituted phenylene structures) on the molecular weight and thermal properties of the synthesized poly (amide-ester) s were investigated in this study. When a portion of the amide groups were replaced with the ester groups, most of the synthesized poly(amide-ester)s containing naphthalene or substituted hydroquinone units showed excellent mesophase and thermal stability, but the poly(amide-ester)s containing bisphenyl structures lost the mesophase behaviors. The P3 series of poly(amide-ester)s derived from TPA and 2,6-naphthalene dicarboxlic acid with phenylhydroquinone and various diamines possess liquid crystalline properties, even some of the diamines containing kink structures.  相似文献   

16.
Rigid-rod conjugated poly(aryleneethynylenevinylene)s were prepared from diethynyl aromatic compounds containing alkoxy groups and trans,trans-1,4-bis(β-bromoviny ])benzene by palladium-catalyzed coupling reaction. Polymerizations were carried out in THF in the presence of Pd catalyst, CuI and diethyl amine and gave a series of poly(aryleneethynylenevinylene)s with weight average molecular weight up to 56,000. The characterization of polymers by IR, NMR, UV-Vis, thermogravimetry, DSC, optical microscopy and X-ray are reported. The polymers exhibited intense fluorescence in solution (THF) and absorption band shifted to longer wavelength in films of the polymers. Polymers with long alkoxy side chains showed good solubility in THF, CH2Cl2 and CHCl3.  相似文献   

17.
Sulfonated poly(amide‐imide) (SPAI) copolymer was synthesized, characterized, and blended into poly(ether sulfone) (PES)/dimethylacetamide casting solutions to prepare ultrafiltration membranes. Different weight ratios of the copolymer (0–10 wt %) were mixed in the PES casting solution. The analyses of contact angle and attenuated total reflection‐Fourier transform infrared spectra were used to study hydrophilicity and physicochemical properties of the membrane surface, respectively. The membranes were further characterized by scanning electron microscopy images, ultrafiltration performance, and fouling analyses. The outcomes showed that addition of the SPAI in the PES matrix improved considerably the membranes hydrophilicity. Moreover, with increasing SPAI concentration, the porosity, flux recovery ratio, and pure water permeability of the modified membranes were improved. The pure water flux was increased from 3.6 to 12.4 kg/m2 h by increasing 2 wt % SPAI. The antifouling property of the modified PES membranes against bovine serum albumin, tested by a dead‐end filtration setup revealed that bovine serum albumin rejection of the obtained membrane was also enhanced and the antifouling properties of the blending membranes were improved. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46477.  相似文献   

18.
A series of poly(azomethine ester) copolymers were synthesized by the solution polycondensation method with different diamines. The synthesized polymers were characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis, differential scanning calorimetry (DSC), hot‐stage polarized microscopy, wide‐angle X‐ray diffraction, and solution viscosity. All polymers showed good thermal stability. The thermotropic liquid‐crystalline properties were examined by DSC and by microscopic observations. Except for one, all of the polymers showed nematic liquid‐crystalline behavior. The effects of temperature on crystallinity and the substituent on solubility, thermal stability, melting temperature, and viscosity were also studied. The voluminosity and shape factor were also computed from the viscosity data. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 153–160, 2003  相似文献   

19.
Development of alternate materials to Nafion, based on ionically conducting polymers and their blends is important for the wider applications of proton exchange membrane fuel cells. In this work, blends of sulfonated poly(ether ether ketone) (SPEEK) with poly(ether sulfone) (PES) are investigated. SPEEK with various ion exchange capacity (IEC) was prepared and blended with PES, which is nonionic and hydrophobic in nature. A comparative study of the water uptake, proton conductivity, and thermo‐mechanical characteristics of SPEEK and the blend membranes as a function of the IEC is presented. Addition of PES decreases the water uptake and conductivity of SPEEK. Chemical and thermal stability and mechanical properties of the membrane improve with the addition of PES. The effect of water content on the thermo‐mechanical properties of membranes was also studied. The morphology of blend membranes was studied using SEM to understand the microstructure and miscibility of the components. On the basis of the results, a plausible microstructure of the blends is presented, and is shown to be useful in understanding the variation of different properties with blending. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013  相似文献   

20.
A new naphthalene‐ring‐containing bis(ester–amine), 1,5‐bis(3‐aminobenzoyloxy)naphthalene, was prepared from the condensation of 1,5‐dihydroxynaphthalene with 3‐nitrobenzoyl chloride followed by catalytic hydrogenation. A series of novel naphthalene‐containing poly(ester–amide)s was synthesized by direct phosphorylation polyamidation from this bis(ester–amine) with various aromatic dicarboxylic acids. The polymers were produced in high yields and had moderate inherent viscosities of 0.47–0.81 dL g?1. The poly(ester–amide) derived from terephthalic acid was semicrystalline and showed less solubility. Other polymers derived from less rigid and symmetrical diacids were amorphous and readily soluble in most polar organic solvents and could be solution‐cast into transparent, flexible and tough films with good mechanical properties. The amorphous poly(ester–amide)s displayed well‐defined glass transition temperatures of between 179 and 225 °C from differential scanning calorimetry and softening temperatures of between 178 and 211 °C from thermomechanical analysis. These poly(ester–amide)s did not show significant decomposition below 400 °C in nitrogen or air. Copyright © 2004 Society of Chemical Industry  相似文献   

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