A novel type of aromatic poly( ether ether ketone) s with carboxyl groups were prepared by polycondensation of 4,4-bis(4-hydroxyphenyl)pentanoic acid with difluoro-monomers. Their mo- lecular structures were deter...A novel type of aromatic poly( ether ether ketone) s with carboxyl groups were prepared by polycondensation of 4,4-bis(4-hydroxyphenyl)pentanoic acid with difluoro-monomers. Their mo- lecular structures were determined by ^1H-NMR and IR, respectively. Their molecular weights were measured by gel permeation chromatography ( GPC ), which showed that all the polymers had high molecule weights ( 〉 42 000). Due to the long side chains of polymers, all the polymers had good solubility (soluble in NMP, DMAc, THF, etc. ). The differential scanning calorimeter (DSC) detected their excellent glass transition temperatures ( Tg ) up to 195 ℃. The Tg increased with the content of carboxylic units in the polymer chains, because the interactions of H bonds increased with increasing content of carboxylic. The polymers could form transparent and flexible films, which make them a candidate for membrane materials.展开更多
Photo-grafting of hydrophilic monomer was used to enhance the hydrophilicity of poly(ether ether ketone) (PEEK) with the aim of extending its applications to biological fields. PEEK sheets were surface modified by...Photo-grafting of hydrophilic monomer was used to enhance the hydrophilicity of poly(ether ether ketone) (PEEK) with the aim of extending its applications to biological fields. PEEK sheets were surface modified by grafting of acrylamide(AAm) with ultraviolet(UV) irradiation in the presence or absence of benzophenone(BP). The effects of BP, irradiation time and monomer concentration on the surface wettability of PEEK were investigated. Characteriza tion of modified PEEK using scanning electron microscopy(SEM), energy-disperse spectrometer(EDS) and water contact angle measurements shows that AAm was successfully grafted on PEEK surface both in presence and absence of BP. With the increase in irradiation time and monomer concentration, contact angles decrease to as low as 30°, demonstrating a significant improvement of surface hydrophilicity. In agreement with the decrease in contact angle, under identical conditions, the nitrogen concentration increases, suggesting the increase in grafting degree of the grafting polymerization. This investigation demonstrates a self-initiation of PEEK due to its BP-like structure in the backbone of the polymer. Though the graft polymerization proceeds more readily in the presence of BP, the self-initiated graft polymerization is clearly observed.展开更多
A sulfonated poly(ether ether ketone) (SPEEK) membrane with a fairly high degree of sulfonation (DS) can swell excessively and even dissolve at high temperature. To solve these problems, insolvable functionalize...A sulfonated poly(ether ether ketone) (SPEEK) membrane with a fairly high degree of sulfonation (DS) can swell excessively and even dissolve at high temperature. To solve these problems, insolvable functionalized silica powder with sulfonic acid groups (SiOx-S) was added into the SPEEK matrix (DS = 55.1%) to prepare SPEEK/ SiOx-S composite membranes. The decrease in both the swelling degree and the methanol permeability of the membranes was a dose-dependent result of addition of the SiOx-S powder. Pure SPEEK membrane swelled 52.6% at 80℃, whereas the SPEEK/SiOx-S (15%, by mass) membrane swelled only 27.3% at the same temperature. From room temperature to 80℃, all SPEEK/SPEEK/SiOx-S composite membranes had methanol permeability of about one order of magnitude lower than that ofNafion115. Compared with pure SPEEK membranes, the addition of the SiOx-S powder not only leads to higher proton conductivity, but also increases the dimensional stability at higher temperatures, and greater proton conductivity can be achieved at higher temperature. The SPEEK/SiO4-S (20%, by mass) membrane could withstand temperature up to 145℃, at which in 100% relative humidity (RH) its proton conductivity exceeded slightly that of Nafion 1 15 membrane and reached 0.17 S·cm^-1, while pure SPEEK membrane dissolved at 90℃. The SPEEK/SiOx-S composite membranes are promising for use in direct methanol fuel cells because of their good dimensional stability, high proton conductivity, and low methanol permeability.展开更多
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 chlorometh...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. Quaternized 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.展开更多
A sulfonated poly(ether ether ketone) (SPEEK) membrane with fairly high degree of sulfonation (DS) swells excessively and even dissolves at high temperature. To solve these problems, sulfonated phenolphthalein p...A sulfonated poly(ether ether ketone) (SPEEK) membrane with fairly high degree of sulfonation (DS) swells excessively and even dissolves at high temperature. To solve these problems, sulfonated phenolphthalein poly(ether sulfone) (SPES-C, DS= 53.7%) is blended with the SPEEK matrix (DS= 55.1%, 61.7%) to prepare SPEEKJSPES-C blend membrane. The decrease in swelling degree and methanol permeability of the membrane is dose-dependent. Pure SPEEK (DS = 61.7%) membrane dissolves completely in water at 70℃, whereas the swelling degree of the SPEEK (DS = 61.7%)/SPES-C (40%, by mass) membrane is 29.7% at 80℃. From room temperature to 80℃, the methanol permeability of all SPEEK (DS = 55.1%)/SPES-C blend membranes is about one order of magnitude lower than that of Nafion 115. At higher temperature, the addition of SPES-C polymer increases the dimensional stability and greater proton conductivity can be achieved. The SPEEK (DS = 55.1%)/SPES-C (40%, by mass) membrane can withstand temperatures up to 150℃. The proton conductivity of SPEEK (DS = 55.1%)/SPES-C (30%, by mass) membrane approaches 0.16 S·cm^-1, matching that of Nafion 115 at 140℃ and 100% RH, while pure SPEEK (DS = 55.1%) membrane dissolves at 90℃. The SPEEK/SPES-C blend membranes are promising for use in direct methanol fuel cells because of their good dimensional stability, high proton conductivity, and low methanol permeability.展开更多
UV-induced graft polymerization of acrylic acid(AA) on poly(ether ether ketone)(PEEK) films was carried out to introduce ―COOH for the subsequent immobilization of bovine serum albumin(BSA).BSA was introduced...UV-induced graft polymerization of acrylic acid(AA) on poly(ether ether ketone)(PEEK) films was carried out to introduce ―COOH for the subsequent immobilization of bovine serum albumin(BSA).BSA was introduced on PEEK surface based on the condensation reaction between ―NH 2 and ―COOH.The modified surface(PEEK-BSA) was characterized by energy-disperse spectrometry(EDS),X-ray photoelectron spectroscopy(XPS),water contact angle measurement and UV spectrum analysis.The contact angle was found to decrease from 104° for the virgin PEEK films to 63° for the BSA-immobilized PEEK films,demonstrating a significant improvement of surface hydrophilicity.Moreover,the appearance of nitrogen on PEEK film confirmed by XPS and EDS indicates the immobilization of BSA on PEEK surface.展开更多
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...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).展开更多
A new monomer, 1,4-bis(4-fluorobenzoyl) naphthalene(compound 2) was synthesized via a two-step reaction. 1,4-Naphthalenedicarboxylic acid chloride(compound 1) was prepared by using the acyl chlorization reaction of 1,...A new monomer, 1,4-bis(4-fluorobenzoyl) naphthalene(compound 2) was synthesized via a two-step reaction. 1,4-Naphthalenedicarboxylic acid chloride(compound 1) was prepared by using the acyl chlorization reaction of 1,4-naphthalenedicarboxylic acid with thionyl chloride. The Friedel-Crafts acylation of compound 1 with fluorobenzene afforded compound 2 in a 80% yield. The polycondensation of compound 2 with various bisphenols in tetramethylene sulfone(TMS) in the presence of excess potassium carbonate as a condensation reagent was carried out at 210 ℃ to quantitatively afford the corresponding poly(aryl ether ketone)s(compounds 3_8) containing 1,4-naphthalene moieties. Thermal analyses showed that the polymers have T g values ranging from 496 to 500 K and are thermally stable in air with initial mass loss above 500 ℃. These novel polymers exhibited an excellent solubility in organic solvents including NMP, DMAc, and chloroform, etc. In addition, the glass transition temperatures of these polymers increased and the polymers became insoluble in chloroform after treated at 260 ℃, indicating the occurrence of a thermal crosslinking reaction.展开更多
1, 2-Diliydro-4-(4-hydroxyphenyl)(2H)phthalazin-1-one(DHPZ) was sulfonated in concentrated Sulfuric acid. Poly(phthalazinone ether ketone) containing pendant sodium sulfonate group was synthesized from sulfonated and ...1, 2-Diliydro-4-(4-hydroxyphenyl)(2H)phthalazin-1-one(DHPZ) was sulfonated in concentrated Sulfuric acid. Poly(phthalazinone ether ketone) containing pendant sodium sulfonate group was synthesized from sulfonated and pure 1,2-dihydro-4-(4-hydroxyphenyl)(2H)phthalazin-1-one, and 4,4'-difluorodiphenylketone. The sulfonated monomer and sulfonated polymer were characterized with FT-IR and H-1-NMR.展开更多
An imidazolium functionalized poly(ether ether ketone ketone)(PEEKK-DIm OH)anion exchange membrane(AEM)readily soluble in certain low-boiling-point solvents(isopropanol)is prepared.The solubility results are consisten...An imidazolium functionalized poly(ether ether ketone ketone)(PEEKK-DIm OH)anion exchange membrane(AEM)readily soluble in certain low-boiling-point solvents(isopropanol)is prepared.The solubility results are consistent with the results of molecular dynamics simulations.By varying the chloromethylation reaction temperature or concentrated sulfuric acid concentration of PEEKK,the degrees of chloromethylation of PEEKK are changed from 54% to 92%,the corresponding PEEKK-DIm OH AEMs with the ion exchange capacities(IECs)of 1.14–1.65 mmol·g^(-1).The PEEKK-DIm OH 92% AEM shows high hydroxide conductivity(31 m S·cm^(-1)),suitable water uptake(94%)and acceptable swelling ratio(39%)at 60°C.In addition,the PEEKK-DIm OH AEMs possess good thermal and alkaline stability.The maximum power density(46.16 mW·cm^(-2))of fuel cell prepared with PEEKK-DIm OH 92%AEM as exchange membrane and ionomer is much higher than that with commercial AHA membranes.All the above results indicate that the PEEKK used in this study is a promising AEM matrix material for alkaline fuel cells.展开更多
Trimethoxysilyl-functionalized PPEK(PKGS) films had been designed to serve as wear resistant coatings for silicon surfaces. These surface films were formed by a dip-coating technique applied to self-assembled monola...Trimethoxysilyl-functionalized PPEK(PKGS) films had been designed to serve as wear resistant coatings for silicon surfaces. These surface films were formed by a dip-coating technique applied to self-assembled monolayers(SAMs).The formation and wetting behavior of PKGS films were characterized by means of contact angle measurement.The friction coefficient of the film prepared is very low(about 0.1),and the anti-wear behavior is good,with a lack of failure after sliding over 1800 s.展开更多
A new poly(aryl ether ketone) containing biphenylphthalazinone moiety was prepared by the reaction of 4-(4-hydroxybiphenyl) phthalazine-1-one with 4, 4'-difluorobenzophenone. The monomer and the polymer were chara...A new poly(aryl ether ketone) containing biphenylphthalazinone moiety was prepared by the reaction of 4-(4-hydroxybiphenyl) phthalazine-1-one with 4, 4'-difluorobenzophenone. The monomer and the polymer were characterized by FT-IR and H-1-NMR. Some properties of this polymer were described.展开更多
A novel soluble poly(aryl ether ketone) was prepared by the reaction of 4-(3-phenyl-4-hydroxyphenyl)phthalazinone with 4,4'-difluorobenzophenone. The polymer was characterized by DSC, TGA and X-ray diffraction.
A novel heterocyclic poly (aryl ether ketone ketone) (PPEKK) containing cyclohexenering was prepared from 1-methyl-cyclohex-1-ene-4, 5 -diyl-bis(4-chlorophenyl methanone) and 4 (4-hydroxyphenyl)(2H) phthalazin-1-one. ...A novel heterocyclic poly (aryl ether ketone ketone) (PPEKK) containing cyclohexenering was prepared from 1-methyl-cyclohex-1-ene-4, 5 -diyl-bis(4-chlorophenyl methanone) and 4 (4-hydroxyphenyl)(2H) phthalazin-1-one. The polymer was characterized by FTIR, 1HNMR, DSC,TG and X-ray analysis.展开更多
Poly( aryl ether ketone) copolymers containing 2,7-naphthylene and hydroquinone(HQ) moieties with various compositions were prepared by the reaction of 4,4'-difluorobenzophenone(DFB) 2,7-naphthylene and hydroqu...Poly( aryl ether ketone) copolymers containing 2,7-naphthylene and hydroquinone(HQ) moieties with various compositions were prepared by the reaction of 4,4'-difluorobenzophenone(DFB) 2,7-naphthylene and hydroquinone in the presence of sodium carbonate and potassium carbonate ( 19: 1, mass ratio) in diphenyl sulfone (DPS). The thermal analysis results of the copolymers show that the glass transition temperatures(Tgs) increase, while the melting temperatures(Tra) and tile 5.0% weight loss temperatures ( Td ) decrease with the increase of the 2,7-naphthalene moieties. For the copolymers synthesized at a molar fraction of 2,7-naphthalene in the difluoro monomers being over 0.30, no peaks corresponding to the cold crystallization temperature and the melting temperature could be detected, indicating that these copolymers are almost amorphous. The crystal structures of the copolymers with a molar fraction of 2,7-naphthalene being less than 0. 30 are rhombic.展开更多
A phosphrous-containing poly(aryl ether ketone) was synthesized derived from bisphenol-A and bis[4-(4- fluorobenzoyl)phenyl] phenyl phosphine oxide (FPPPO) by nucleophilic substitution reaction. The structure of...A phosphrous-containing poly(aryl ether ketone) was synthesized derived from bisphenol-A and bis[4-(4- fluorobenzoyl)phenyl] phenyl phosphine oxide (FPPPO) by nucleophilic substitution reaction. The structure of the polymer was characterized by FT-IR, ^1H-NMR and ^31p-NMR. The thermal property of the PAEK was measured by DSC and TGA. The glass transition temperature (Tg) of the polymer was 205℃, and the 5% weight loss temperature under nitrogen was 475℃. Good solubility of the polymer in organic solvents, such as N-methylpyrrolidone, dimethylformamide, dimethylacetamide, dimethylsulfoxide and chloroalkanes was observed, flexible film was obtained from the polymer's CH2Cl2 solution. The limiting oxygen index (LOI) of the PAEK was 40, which indicated that organic phosphorus moiety can offer good flame retardant property to the polymer.展开更多
Proton conducting composite membranes from sulfonated polyether ether ketone and SiO2 for direct methanol fuel cell (DMFC) application were prepared with sulfonated polyether ether ketone(SPEEK) and tetracethoxy s...Proton conducting composite membranes from sulfonated polyether ether ketone and SiO2 for direct methanol fuel cell (DMFC) application were prepared with sulfonated polyether ether ketone(SPEEK) and tetracethoxy silane(TEOS) by sol-gel method. The covalent crosslinking structure was formed between —SO3H of SPEEK via SiO2. The SEM images show that the interfacial compatibility of SPEEK and SiO2 is improved obviously and SiO2 disperses uniformly in the polymer matrix and the particle diameter of SiO2 does not exceed 40 nm. The proton conductivity of composite membranes decreases slightly compared with the SPEEK membrane while the methanol permeability and swelling of composite membrane are improved remarkablely owing to covalent cross-linking between —SO3H and SiO2 .展开更多
Poly(ether ether ketone)(PEEK)has drown researchers’wide attention because of the exceptional performances such as mechanical properties,thermal stability,chemical resistance,and biocompatibility.These properties end...Poly(ether ether ketone)(PEEK)has drown researchers’wide attention because of the exceptional performances such as mechanical properties,thermal stability,chemical resistance,and biocompatibility.These properties endow it with broad potential use in biomedical,engineering,and aerospace applications.In addition,multifunctional fillers have been intensively incorporated into PEEK matrix,as it is conducive to the enhanced properties,and has the desired properties in concrete applications.This review introduced the basic content and synthesis pathway of PEEKs and their composites,focusing on the various applications,including biomedical,machinery,energy storage,and aerospace applications.Considerable efforts have been devoted to explore the concrete modified method to obtain the desired performances of PEEK based materials.At the end,existing problems and development directions for the PEEK based materials were analyzed and predicted.展开更多
A series of Poly(arly ether sulfone ether ketone)s containing pendant methyl groups were synthesized by the reaction of 4,4'-[sulfonylbis (1,4-phenylene)dioxy] dibenzoyl chloride (SODBC) with 4,4'- diphenoxy d...A series of Poly(arly ether sulfone ether ketone)s containing pendant methyl groups were synthesized by the reaction of 4,4'-[sulfonylbis (1,4-phenylene)dioxy] dibenzoyl chloride (SODBC) with 4,4'- diphenoxy diphenylsulfone (DPODPS), 4,4'- di(2-methylphenoxy) diphenylsulfone (o-Me-DPODPS), 4,4'- di(3-methylphenoxy) diphenylsulfone (m-Me-DPODPS), 4,4'- di (2,6-bimethylphenoxy) biphenylsulfone(o-Me2-DPODPS) respectively, in a mixture of 1,2-dichloroethane (DCE) and N-methylpyrrolidone (NMP). These reactions were catalyzed by anhydrous aluminum chloride (AlCl). The characteristic of copolymers were studied by means of advanced analytical techniques such as FT-IR,1H-NMR, DSC, TGA and WAXD. The results show glass transition temperature (Tg) in the range of 193-206℃, thermally stable in excess of 434℃ and excellent solubility in polar solvents. Methyl-substituted Poly(aryl ether sulfone ketone)s had higher glass transition temperatures, lower initial decomposition temperatures than the unsubstituted ones.展开更多
基金Supported by Open Project of State Key Laboratory of Supramolecular Structure and Materials(SKLSSM201114)the National Natural Science Foundation of China(51103010)
文摘A novel type of aromatic poly( ether ether ketone) s with carboxyl groups were prepared by polycondensation of 4,4-bis(4-hydroxyphenyl)pentanoic acid with difluoro-monomers. Their mo- lecular structures were determined by ^1H-NMR and IR, respectively. Their molecular weights were measured by gel permeation chromatography ( GPC ), which showed that all the polymers had high molecule weights ( 〉 42 000). Due to the long side chains of polymers, all the polymers had good solubility (soluble in NMP, DMAc, THF, etc. ). The differential scanning calorimeter (DSC) detected their excellent glass transition temperatures ( Tg ) up to 195 ℃. The Tg increased with the content of carboxylic units in the polymer chains, because the interactions of H bonds increased with increasing content of carboxylic. The polymers could form transparent and flexible films, which make them a candidate for membrane materials.
基金Supported by the Scientific and Technological Development Programs of Beijing Municipal Education Commission, China (No.KM201010011004)the Scientific Research Foundation for the Returned Overseas Chinese Scholars, Ministry of Education, China, the 2011 Merit-based Research Funding for Picked Returned Overseas Scholars, Beijing Municipality, ChinaBeijing Technology and Business University Through a Research Project Approved for Undergraduates
文摘Photo-grafting of hydrophilic monomer was used to enhance the hydrophilicity of poly(ether ether ketone) (PEEK) with the aim of extending its applications to biological fields. PEEK sheets were surface modified by grafting of acrylamide(AAm) with ultraviolet(UV) irradiation in the presence or absence of benzophenone(BP). The effects of BP, irradiation time and monomer concentration on the surface wettability of PEEK were investigated. Characteriza tion of modified PEEK using scanning electron microscopy(SEM), energy-disperse spectrometer(EDS) and water contact angle measurements shows that AAm was successfully grafted on PEEK surface both in presence and absence of BP. With the increase in irradiation time and monomer concentration, contact angles decrease to as low as 30°, demonstrating a significant improvement of surface hydrophilicity. In agreement with the decrease in contact angle, under identical conditions, the nitrogen concentration increases, suggesting the increase in grafting degree of the grafting polymerization. This investigation demonstrates a self-initiation of PEEK due to its BP-like structure in the backbone of the polymer. Though the graft polymerization proceeds more readily in the presence of BP, the self-initiated graft polymerization is clearly observed.
基金Supported by the State Key Development Program for Basic Research of China (2008CB617502), the National Natural Science Foundation of China (20606025), and Program for Changjiang Scholars and Innovative Research Team in University of China (IRT0641).
文摘A sulfonated poly(ether ether ketone) (SPEEK) membrane with a fairly high degree of sulfonation (DS) can swell excessively and even dissolve at high temperature. To solve these problems, insolvable functionalized silica powder with sulfonic acid groups (SiOx-S) was added into the SPEEK matrix (DS = 55.1%) to prepare SPEEK/ SiOx-S composite membranes. The decrease in both the swelling degree and the methanol permeability of the membranes was a dose-dependent result of addition of the SiOx-S powder. Pure SPEEK membrane swelled 52.6% at 80℃, whereas the SPEEK/SiOx-S (15%, by mass) membrane swelled only 27.3% at the same temperature. From room temperature to 80℃, all SPEEK/SPEEK/SiOx-S composite membranes had methanol permeability of about one order of magnitude lower than that ofNafion115. Compared with pure SPEEK membranes, the addition of the SiOx-S powder not only leads to higher proton conductivity, but also increases the dimensional stability at higher temperatures, and greater proton conductivity can be achieved at higher temperature. The SPEEK/SiO4-S (20%, by mass) membrane could withstand temperature up to 145℃, at which in 100% relative humidity (RH) its proton conductivity exceeded slightly that of Nafion 1 15 membrane and reached 0.17 S·cm^-1, while pure SPEEK membrane dissolved at 90℃. The SPEEK/SiOx-S composite membranes are promising for use in direct methanol fuel cells because of their good dimensional stability, high proton conductivity, and low methanol permeability.
基金partly financed by the Major State Basic Research Development Program of China(No.2003 CB615700)the National Natural Science Foundation of China(No.20604005).
文摘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. Quaternized 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.
基金Supported by the State Key Development Program for Basic Research of China (2008CB617502), the National Natural Science Foundation of China (20606025), and Program for Changjiang Scholars and Innovative Research Team in University of China (IRT0641).
文摘A sulfonated poly(ether ether ketone) (SPEEK) membrane with fairly high degree of sulfonation (DS) swells excessively and even dissolves at high temperature. To solve these problems, sulfonated phenolphthalein poly(ether sulfone) (SPES-C, DS= 53.7%) is blended with the SPEEK matrix (DS= 55.1%, 61.7%) to prepare SPEEKJSPES-C blend membrane. The decrease in swelling degree and methanol permeability of the membrane is dose-dependent. Pure SPEEK (DS = 61.7%) membrane dissolves completely in water at 70℃, whereas the swelling degree of the SPEEK (DS = 61.7%)/SPES-C (40%, by mass) membrane is 29.7% at 80℃. From room temperature to 80℃, the methanol permeability of all SPEEK (DS = 55.1%)/SPES-C blend membranes is about one order of magnitude lower than that of Nafion 115. At higher temperature, the addition of SPES-C polymer increases the dimensional stability and greater proton conductivity can be achieved. The SPEEK (DS = 55.1%)/SPES-C (40%, by mass) membrane can withstand temperatures up to 150℃. The proton conductivity of SPEEK (DS = 55.1%)/SPES-C (30%, by mass) membrane approaches 0.16 S·cm^-1, matching that of Nafion 115 at 140℃ and 100% RH, while pure SPEEK (DS = 55.1%) membrane dissolves at 90℃. The SPEEK/SPES-C blend membranes are promising for use in direct methanol fuel cells because of their good dimensional stability, high proton conductivity, and low methanol permeability.
基金Supported by the Scientific and Technological Development Programs of Beijing Municipal Education Commission,China(No.KM201010011004)the Scientific Research Foundation for the Returned Overseas Chinese Scholars,Ministry of Education,China,the 2011 Merit-based Research Funding for Picked Returned Overseas Scholars,Beijing Municipality(China)the Research Project Approved for Graduate Students of Beijing Technology and Business University,China(No.19000101026)
文摘UV-induced graft polymerization of acrylic acid(AA) on poly(ether ether ketone)(PEEK) films was carried out to introduce ―COOH for the subsequent immobilization of bovine serum albumin(BSA).BSA was introduced on PEEK surface based on the condensation reaction between ―NH 2 and ―COOH.The modified surface(PEEK-BSA) was characterized by energy-disperse spectrometry(EDS),X-ray photoelectron spectroscopy(XPS),water contact angle measurement and UV spectrum analysis.The contact angle was found to decrease from 104° for the virgin PEEK films to 63° for the BSA-immobilized PEEK films,demonstrating a significant improvement of surface hydrophilicity.Moreover,the appearance of nitrogen on PEEK film confirmed by XPS and EDS indicates the immobilization of BSA on PEEK surface.
文摘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).
基金Supported by the National Natural Science Foundation of China(No.5 0 2 0 30 0 4 )
文摘A new monomer, 1,4-bis(4-fluorobenzoyl) naphthalene(compound 2) was synthesized via a two-step reaction. 1,4-Naphthalenedicarboxylic acid chloride(compound 1) was prepared by using the acyl chlorization reaction of 1,4-naphthalenedicarboxylic acid with thionyl chloride. The Friedel-Crafts acylation of compound 1 with fluorobenzene afforded compound 2 in a 80% yield. The polycondensation of compound 2 with various bisphenols in tetramethylene sulfone(TMS) in the presence of excess potassium carbonate as a condensation reagent was carried out at 210 ℃ to quantitatively afford the corresponding poly(aryl ether ketone)s(compounds 3_8) containing 1,4-naphthalene moieties. Thermal analyses showed that the polymers have T g values ranging from 496 to 500 K and are thermally stable in air with initial mass loss above 500 ℃. These novel polymers exhibited an excellent solubility in organic solvents including NMP, DMAc, and chloroform, etc. In addition, the glass transition temperatures of these polymers increased and the polymers became insoluble in chloroform after treated at 260 ℃, indicating the occurrence of a thermal crosslinking reaction.
基金the National Natural Science Foundation of China for financial support.
文摘1, 2-Diliydro-4-(4-hydroxyphenyl)(2H)phthalazin-1-one(DHPZ) was sulfonated in concentrated Sulfuric acid. Poly(phthalazinone ether ketone) containing pendant sodium sulfonate group was synthesized from sulfonated and pure 1,2-dihydro-4-(4-hydroxyphenyl)(2H)phthalazin-1-one, and 4,4'-difluorodiphenylketone. The sulfonated monomer and sulfonated polymer were characterized with FT-IR and H-1-NMR.
基金Supported by the National Natural Science Foundation of China(21706023,21476044,21406031)the National Key Research and Development Program of China(2016YFB0101203)+2 种基金Education Department of Liaoning Province of China(LT2015007)Fundamental Research Funds for the Central Universities(DUT16TD19)the Changjiang Scholars Program(T2012049)
文摘An imidazolium functionalized poly(ether ether ketone ketone)(PEEKK-DIm OH)anion exchange membrane(AEM)readily soluble in certain low-boiling-point solvents(isopropanol)is prepared.The solubility results are consistent with the results of molecular dynamics simulations.By varying the chloromethylation reaction temperature or concentrated sulfuric acid concentration of PEEKK,the degrees of chloromethylation of PEEKK are changed from 54% to 92%,the corresponding PEEKK-DIm OH AEMs with the ion exchange capacities(IECs)of 1.14–1.65 mmol·g^(-1).The PEEKK-DIm OH 92% AEM shows high hydroxide conductivity(31 m S·cm^(-1)),suitable water uptake(94%)and acceptable swelling ratio(39%)at 60°C.In addition,the PEEKK-DIm OH AEMs possess good thermal and alkaline stability.The maximum power density(46.16 mW·cm^(-2))of fuel cell prepared with PEEKK-DIm OH 92%AEM as exchange membrane and ionomer is much higher than that with commercial AHA membranes.All the above results indicate that the PEEKK used in this study is a promising AEM matrix material for alkaline fuel cells.
基金This project was financially supported by National High Technology and Development Program of China(863 Program)(No.2003AA33G030)
文摘Trimethoxysilyl-functionalized PPEK(PKGS) films had been designed to serve as wear resistant coatings for silicon surfaces. These surface films were formed by a dip-coating technique applied to self-assembled monolayers(SAMs).The formation and wetting behavior of PKGS films were characterized by means of contact angle measurement.The friction coefficient of the film prepared is very low(about 0.1),and the anti-wear behavior is good,with a lack of failure after sliding over 1800 s.
基金This work was supported by the National Natural Science Foundation of China.
文摘A new poly(aryl ether ketone) containing biphenylphthalazinone moiety was prepared by the reaction of 4-(4-hydroxybiphenyl) phthalazine-1-one with 4, 4'-difluorobenzophenone. The monomer and the polymer were characterized by FT-IR and H-1-NMR. Some properties of this polymer were described.
基金This work was supported by the National Natural Science Foundation.
文摘A novel soluble poly(aryl ether ketone) was prepared by the reaction of 4-(3-phenyl-4-hydroxyphenyl)phthalazinone with 4,4'-difluorobenzophenone. The polymer was characterized by DSC, TGA and X-ray diffraction.
文摘A novel heterocyclic poly (aryl ether ketone ketone) (PPEKK) containing cyclohexenering was prepared from 1-methyl-cyclohex-1-ene-4, 5 -diyl-bis(4-chlorophenyl methanone) and 4 (4-hydroxyphenyl)(2H) phthalazin-1-one. The polymer was characterized by FTIR, 1HNMR, DSC,TG and X-ray analysis.
文摘Poly( aryl ether ketone) copolymers containing 2,7-naphthylene and hydroquinone(HQ) moieties with various compositions were prepared by the reaction of 4,4'-difluorobenzophenone(DFB) 2,7-naphthylene and hydroquinone in the presence of sodium carbonate and potassium carbonate ( 19: 1, mass ratio) in diphenyl sulfone (DPS). The thermal analysis results of the copolymers show that the glass transition temperatures(Tgs) increase, while the melting temperatures(Tra) and tile 5.0% weight loss temperatures ( Td ) decrease with the increase of the 2,7-naphthalene moieties. For the copolymers synthesized at a molar fraction of 2,7-naphthalene in the difluoro monomers being over 0.30, no peaks corresponding to the cold crystallization temperature and the melting temperature could be detected, indicating that these copolymers are almost amorphous. The crystal structures of the copolymers with a molar fraction of 2,7-naphthalene being less than 0. 30 are rhombic.
基金This work was supported by the National Natural Science Foundation of China(No.50203008).
文摘A phosphrous-containing poly(aryl ether ketone) was synthesized derived from bisphenol-A and bis[4-(4- fluorobenzoyl)phenyl] phenyl phosphine oxide (FPPPO) by nucleophilic substitution reaction. The structure of the polymer was characterized by FT-IR, ^1H-NMR and ^31p-NMR. The thermal property of the PAEK was measured by DSC and TGA. The glass transition temperature (Tg) of the polymer was 205℃, and the 5% weight loss temperature under nitrogen was 475℃. Good solubility of the polymer in organic solvents, such as N-methylpyrrolidone, dimethylformamide, dimethylacetamide, dimethylsulfoxide and chloroalkanes was observed, flexible film was obtained from the polymer's CH2Cl2 solution. The limiting oxygen index (LOI) of the PAEK was 40, which indicated that organic phosphorus moiety can offer good flame retardant property to the polymer.
文摘Proton conducting composite membranes from sulfonated polyether ether ketone and SiO2 for direct methanol fuel cell (DMFC) application were prepared with sulfonated polyether ether ketone(SPEEK) and tetracethoxy silane(TEOS) by sol-gel method. The covalent crosslinking structure was formed between —SO3H of SPEEK via SiO2. The SEM images show that the interfacial compatibility of SPEEK and SiO2 is improved obviously and SiO2 disperses uniformly in the polymer matrix and the particle diameter of SiO2 does not exceed 40 nm. The proton conductivity of composite membranes decreases slightly compared with the SPEEK membrane while the methanol permeability and swelling of composite membrane are improved remarkablely owing to covalent cross-linking between —SO3H and SiO2 .
基金National Natural Science Foundation of China(Grant Nos.11632005,11672086 and 11802077)the Foundation for Innovative Research Groups of the National Natural Science Foundation of China(Grant No.11421091).
文摘Poly(ether ether ketone)(PEEK)has drown researchers’wide attention because of the exceptional performances such as mechanical properties,thermal stability,chemical resistance,and biocompatibility.These properties endow it with broad potential use in biomedical,engineering,and aerospace applications.In addition,multifunctional fillers have been intensively incorporated into PEEK matrix,as it is conducive to the enhanced properties,and has the desired properties in concrete applications.This review introduced the basic content and synthesis pathway of PEEKs and their composites,focusing on the various applications,including biomedical,machinery,energy storage,and aerospace applications.Considerable efforts have been devoted to explore the concrete modified method to obtain the desired performances of PEEK based materials.At the end,existing problems and development directions for the PEEK based materials were analyzed and predicted.
基金This work was supported by National Science Foundation of China (No. 20264001 ), National Science Foundation of Jiangxi Province, Innovation Fund for Technology Based Firms of China (No. 06C26213601342).
文摘A series of Poly(arly ether sulfone ether ketone)s containing pendant methyl groups were synthesized by the reaction of 4,4'-[sulfonylbis (1,4-phenylene)dioxy] dibenzoyl chloride (SODBC) with 4,4'- diphenoxy diphenylsulfone (DPODPS), 4,4'- di(2-methylphenoxy) diphenylsulfone (o-Me-DPODPS), 4,4'- di(3-methylphenoxy) diphenylsulfone (m-Me-DPODPS), 4,4'- di (2,6-bimethylphenoxy) biphenylsulfone(o-Me2-DPODPS) respectively, in a mixture of 1,2-dichloroethane (DCE) and N-methylpyrrolidone (NMP). These reactions were catalyzed by anhydrous aluminum chloride (AlCl). The characteristic of copolymers were studied by means of advanced analytical techniques such as FT-IR,1H-NMR, DSC, TGA and WAXD. The results show glass transition temperature (Tg) in the range of 193-206℃, thermally stable in excess of 434℃ and excellent solubility in polar solvents. Methyl-substituted Poly(aryl ether sulfone ketone)s had higher glass transition temperatures, lower initial decomposition temperatures than the unsubstituted ones.