A ternary hybrid membrane architecture consisting of sulfonated fluorinated multi-block copolymer （SFMC）, sulfonated （poly ether ether ketone） （SPEEK） and I or 5 wt% graphene oxide （GO） was fabricated through ...A ternary hybrid membrane architecture consisting of sulfonated fluorinated multi-block copolymer （SFMC）, sulfonated （poly ether ether ketone） （SPEEK） and I or 5 wt% graphene oxide （GO） was fabricated through a facile solution casting approach. The simple, but effective monomer sulfonation was performed for SFMC to create compact and rigid hydrophobic backbone structures, while conventional random sulfonation was carried-out for SPEEK. Hydrophilic-hydrophobic-hydrophilic structure of SFMC enhances the compatibility with SPEEK and GO and allows for an unprecedented approach to alter me- chanical strength and proton conductivity of ternary hybrid membrane, as verified from universal test machine （UTM） curves and alternating current （AC） impedance plots. The impact of GO integration on the morphology and roughness of hybrid membrane was scrutinized using field emission scanning electron microscope （FE-SEM） and atomic force microscope （AFM）. Ternary hybrid showed uniform intercalation of GO nanosheets throughout the entire surface of membrane with an increased surface roughness of 8.91 nm. The constructed ternary hybrid membrane revealed excellent water absorption, ion exchange capacity and gas barrier properties, while retaining reasonable dimensional stability. The well-optimized ternary hybrid membrane containing 5 wt% GO revealed a maximum proton conductivity of 111.9 mS/cm, which is higher by a factor of two-fold with respect to that of bare SFMC membrane. The maximum PEMFC power density of 528.07mW/cm2 was yielded by ternary hybrid membrane at a load current density of 1321.1 mA/cm2 when operating the cell at 70 ℃ under 100% relative humidity （RH）. In comparison, a maximum power density of only 182.06 mW/cm2 was exhibited by the bare SFMC membrane at a load current density of 455.56 mA/cm2 under same operating conditions.展开更多
Acrylic acid (AAc) and styrene (St) were grafted onto poly(vinylidene fluoride) (PVDF) powder or membrane samples by pre-irradiation graft copolymerization.The grafted chains were proved by FT-IR spectroscopy analysis...Acrylic acid (AAc) and styrene (St) were grafted onto poly(vinylidene fluoride) (PVDF) powder or membrane samples by pre-irradiation graft copolymerization.The grafted chains were proved by FT-IR spectroscopy analysis.The degree of grafting (DG) of the grafted PVDF was determined by fluorine elemental analysis (FEA) method,and was compared with the DGs determined by weighing method,acid-base back titration method and quantitative FT-IR method.The results show that the FEA method is accurate,convenient and universal,especially for the grafted polymer powders.展开更多
The development of alkaline fuel cells is moving forward at an accelerated pace,and the application of ether-free bonded polymers to anion exchange membranes(AEMs)has been widely investigated.However,the question of ...The development of alkaline fuel cells is moving forward at an accelerated pace,and the application of ether-free bonded polymers to anion exchange membranes(AEMs)has been widely investigated.However,the question of the“trade-off”between AEM ionic conductivity and dimensional stability remains difficult.The strategy of inducing microphase separation to improve the performance of AEM has attracted much attention recently,but the design of optimal molecular structures is still being explored.Here,this work introduced different ratios of 3-bromo-1,1,1-trifluoroacetone(x=40,50,and 60)into the main chain of poly(p-terphenylene isatin).Because fluorinated groups have excellent hydrophobicity,hydrophilic hydroxyl-containing side chains are introduced to jointly adjust the formation of phase separation structure.The results show that PTI-PTF_(50)-NOH AEM with the appropriate fluorinated group ratio has the best ionic conductivity and alkali stability under the combined effect of both.It has an ionic conductivity of 133.83 mS cm^(-1)at 80°C.In addition,the OH-conductivity remains at 89%of the initial value at 80°C and 3 M KOH for 1056 h of immersion.The cell polarization curve based on PTI-PTF_(50)-NOH shows a power density of 734.76 mW cm^(-2)at a current density of 1807.7 mA cm^(-2).展开更多
Inspired by the concept of "polymer-in-ceramic",a composite poly(ε-caprolactone)(PCL)/ceramic containing LiTFSI is prepared and investigated as a solid electrolyte for all-solid-state batteries.The composit...Inspired by the concept of "polymer-in-ceramic",a composite poly(ε-caprolactone)(PCL)/ceramic containing LiTFSI is prepared and investigated as a solid electrolyte for all-solid-state batteries.The composite with the optimum concentration of 45 wt% LiTFSI and 75 wt% Li1.5Al0.5Ge1.5(PO4)3(LAGP,NASICON-type structure) exhibits a high ionic conductivity(σi=0.17 mS cm-1) at 30℃,a transference number of 0.30,and is stable up to 5.0 V.The composite electrolyte is a flexible and self-standing membrane.Solid-state LiFePO4//Li batteries with this composite electrolyte demonstrate excellent cycling stability with high discharge capacity of 157 mA h g-1,high capacity retention of 96% and coulombic efficiency of 98.5% after 130 cycles at 30℃ and 0.1 C rate.These electrochemical properties are better than other PCL-based allsolid-lithium batteries,and validate the concept of "polymer-in-ceramic" by avoiding the drawback of lower conductivity in prior "polymer-in-ceramic" electrolyte at high concentration of the ceramic.展开更多
A kind of highly fluorinated bisphenol monomer was synthesized. It was characterized by FTIR, 1H NMR and MS. 6F PEEK and 6F PEEKK were prepared via aromatic nucleophilic substitution, based on [3,5 di(trifluoromethyl)...A kind of highly fluorinated bisphenol monomer was synthesized. It was characterized by FTIR, 1H NMR and MS. 6F PEEK and 6F PEEKK were prepared via aromatic nucleophilic substitution, based on [3,5 di(trifluoromethyl)] phenylhydroquinone and difluoro monomers. The T gs of 6F PEEK and 6F PEEKK are 423 and 436 K, respectively. The 6F polymers exhibit a high thermal stability and good solubility. The flexible, creasable and transparent thin films were easily obtained by compression moulding and solution casting.展开更多
A novel crosslinkable fluorinated poly(ether ether ketone) with acetylenylbenzene end groups was prepared by solution condensation. The chemical structure of such polymer was confirmed by FTIR and 1H NMR. The crosslin...A novel crosslinkable fluorinated poly(ether ether ketone) with acetylenylbenzene end groups was prepared by solution condensation. The chemical structure of such polymer was confirmed by FTIR and 1H NMR. The crosslinking behavior and thermal stability were investigated by DSC and TGA respectively. The DSC thermogram for the first heating run shows a glass transition of 6F-PEEK at about 395 K and a exothermic peak correspongding to the self-crosslinking reaction of fluorinated poly(ether ether ketong) at about 700 K. For the second heating run, the exothermic peak disappered and the glass transition shifted to a higher temperature. The crosslinked polymer shown excelent thermal stability and solvent-resistence. The temperature for 5% weight loss was 774 K and the self-crosslinked polymer was no more disolved by polar solvents, which disolved in before crosslinking, such as DMF, DMAc and NMP. This kind of polymer may be a potential material used as electro-optical devices.展开更多
The crosslinkable trifluoromethylated poly(aryl ethers) terminated with phenylethynyl moieties(11F-PAE-PEP)s were prepared in two step syntheses. The structure of 11F-PAE-PEP was confirmed by FTIR and 1H NMR. The cros...The crosslinkable trifluoromethylated poly(aryl ethers) terminated with phenylethynyl moieties(11F-PAE-PEP)s were prepared in two step syntheses. The structure of 11F-PAE-PEP was confirmed by FTIR and 1H NMR. The crosslinking behavior was studied by DSC. There is a remarkable increase of T g after crosslinking of the poly(aryl ethers). The T g values of crosslinked polymers were 437 and 446 K, respectively. The crosslinked polymers could not be soluble in common organic solvents, such as N,N-dimethylformamide, N,N-dimethylacetamide, N-methyl-2-pyrrolidinone, chloroform, and tetrahydrofuran. The temperatures at a 5% mass loss of the crosslinked polymers in air were above 789 K. They showed a good optical property, too. This kind of polymers will be the promising materials used as the microelectronics and optical waveguide devices.展开更多
A kind of high Fluorine-containing poly(aryl ether) without side reaction was synthesized in a two-step synthesis. Its structure was confirmed by FTIR, 1H NMR and 19F NMR. The polymer shows an excellent thermal stabil...A kind of high Fluorine-containing poly(aryl ether) without side reaction was synthesized in a two-step synthesis. Its structure was confirmed by FTIR, 1H NMR and 19F NMR. The polymer shows an excellent thermal stability, good solubility, low water absorption, low dielectric constant and low refractive index. Flexible and transparant thin film can be easily obtained by compression moulding or solution casting. The polymer would be a promising material used for microelectronics and waveguide devices.展开更多
A novel bifluoro-monomer containing naphthalene moieties was synthesized and characterized by using FTIR, MS and NMR. Different poly(aryl ether ketone)s based on 1,4-bis(4,4′-fluorobenzoyl) naphthalene were prepared ...A novel bifluoro-monomer containing naphthalene moieties was synthesized and characterized by using FTIR, MS and NMR. Different poly(aryl ether ketone)s based on 1,4-bis(4,4′-fluorobenzoyl) naphthalene were prepared via aromatic nucleophilic substitution reaction. The polymers with a high molecular weight can be readily obtained due to the highly activity of the used monomer. 3F-PEEK-nK and 6F-PEEK-nK polymers were determined to exhibit good thermal stabilities with high T-g of 450 K and 457 K, respectively. Moreover, these polymers show a satisfactory solubility and can be cast into flexible and transparent films.展开更多
The novel and soluble poly(ether ether ketone)(PEEK)containing fluorin structure(6F-PEEK)was prepared by nucleophilic reaction of 4,4’-difluorobenzophenone,bisphenol A and hexafluobisphenol A in the presence of anhyd...The novel and soluble poly(ether ether ketone)(PEEK)containing fluorin structure(6F-PEEK)was prepared by nucleophilic reaction of 4,4’-difluorobenzophenone,bisphenol A and hexafluobisphenol A in the presence of anhydrous K2CO3 with tetramethylene sulfone as the solvents.The molecular weight of the polymer was determined by GPC.The structure of the polymer was characterized by FTIR,1H NMR and 19F NMR spectroscopies.The glass transition temperature and the temperature for 5% mass loss of 6F-PEEK were 153 and 493 ℃,respectively.The polymer exhibits an excellent thermal stability,mechanical property and solubility.The rate of elongation at break,tensile strength and tensile modulus of 6F-PEEK were 55.2%,66 MPa,and 2.13 GPa,respectively.展开更多
基金supported by the Korea Institute of Energy Technology Evaluation and Planning(KETEP)the Ministry of Trade,Industry&Energy(MOTIE)of the Republic of Korea(No.20164030201070)supported by Basic Science Research Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Science,ICT and future Planning(NRF-2017R1A2B4005230)
文摘A ternary hybrid membrane architecture consisting of sulfonated fluorinated multi-block copolymer （SFMC）, sulfonated （poly ether ether ketone） （SPEEK） and I or 5 wt% graphene oxide （GO） was fabricated through a facile solution casting approach. The simple, but effective monomer sulfonation was performed for SFMC to create compact and rigid hydrophobic backbone structures, while conventional random sulfonation was carried-out for SPEEK. Hydrophilic-hydrophobic-hydrophilic structure of SFMC enhances the compatibility with SPEEK and GO and allows for an unprecedented approach to alter me- chanical strength and proton conductivity of ternary hybrid membrane, as verified from universal test machine （UTM） curves and alternating current （AC） impedance plots. The impact of GO integration on the morphology and roughness of hybrid membrane was scrutinized using field emission scanning electron microscope （FE-SEM） and atomic force microscope （AFM）. Ternary hybrid showed uniform intercalation of GO nanosheets throughout the entire surface of membrane with an increased surface roughness of 8.91 nm. The constructed ternary hybrid membrane revealed excellent water absorption, ion exchange capacity and gas barrier properties, while retaining reasonable dimensional stability. The well-optimized ternary hybrid membrane containing 5 wt% GO revealed a maximum proton conductivity of 111.9 mS/cm, which is higher by a factor of two-fold with respect to that of bare SFMC membrane. The maximum PEMFC power density of 528.07mW/cm2 was yielded by ternary hybrid membrane at a load current density of 1321.1 mA/cm2 when operating the cell at 70 ℃ under 100% relative humidity （RH）. In comparison, a maximum power density of only 182.06 mW/cm2 was exhibited by the bare SFMC membrane at a load current density of 455.56 mA/cm2 under same operating conditions.
基金Supported by National Natural Science Foundation of China (10875164,10805070)the Knowledge Innovation Project of Chinese Academy of Sciences,Shanghai Municipal Commission for Science and Technology (10ZR1436700),and SRF for ROCS of the Ministry of Education
文摘Acrylic acid (AAc) and styrene (St) were grafted onto poly(vinylidene fluoride) (PVDF) powder or membrane samples by pre-irradiation graft copolymerization.The grafted chains were proved by FT-IR spectroscopy analysis.The degree of grafting (DG) of the grafted PVDF was determined by fluorine elemental analysis (FEA) method,and was compared with the DGs determined by weighing method,acid-base back titration method and quantitative FT-IR method.The results show that the FEA method is accurate,convenient and universal,especially for the grafted polymer powders.
基金Natural Science Foundation of China(grant nos 22075031)Jilin Provincial Science&Technology Department(grant nos 20220201105GX)Jilin Provincial Development and Reform Commission(grant nos 2023C034-4)。
文摘The development of alkaline fuel cells is moving forward at an accelerated pace,and the application of ether-free bonded polymers to anion exchange membranes(AEMs)has been widely investigated.However,the question of the“trade-off”between AEM ionic conductivity and dimensional stability remains difficult.The strategy of inducing microphase separation to improve the performance of AEM has attracted much attention recently,but the design of optimal molecular structures is still being explored.Here,this work introduced different ratios of 3-bromo-1,1,1-trifluoroacetone(x=40,50,and 60)into the main chain of poly(p-terphenylene isatin).Because fluorinated groups have excellent hydrophobicity,hydrophilic hydroxyl-containing side chains are introduced to jointly adjust the formation of phase separation structure.The results show that PTI-PTF_(50)-NOH AEM with the appropriate fluorinated group ratio has the best ionic conductivity and alkali stability under the combined effect of both.It has an ionic conductivity of 133.83 mS cm^(-1)at 80°C.In addition,the OH-conductivity remains at 89%of the initial value at 80°C and 3 M KOH for 1056 h of immersion.The cell polarization curve based on PTI-PTF_(50)-NOH shows a power density of 734.76 mW cm^(-2)at a current density of 1807.7 mA cm^(-2).
基金supported by the National Key R&D Program of China (2016YFB0100500)Special fund of key technology research and development projects (20180201097GX) (20180201099GX) (20180201096GX) (20190302130GX)+1 种基金Jilin province science and technology department. The R&D Program of power batteries with low temperature and high energy, Science and Technology Bureau of Changchun (19SS013)Key Subject Construction of Physical Chemistry of Northeast Normal University。
文摘Inspired by the concept of "polymer-in-ceramic",a composite poly(ε-caprolactone)(PCL)/ceramic containing LiTFSI is prepared and investigated as a solid electrolyte for all-solid-state batteries.The composite with the optimum concentration of 45 wt% LiTFSI and 75 wt% Li1.5Al0.5Ge1.5(PO4)3(LAGP,NASICON-type structure) exhibits a high ionic conductivity(σi=0.17 mS cm-1) at 30℃,a transference number of 0.30,and is stable up to 5.0 V.The composite electrolyte is a flexible and self-standing membrane.Solid-state LiFePO4//Li batteries with this composite electrolyte demonstrate excellent cycling stability with high discharge capacity of 157 mA h g-1,high capacity retention of 96% and coulombic efficiency of 98.5% after 130 cycles at 30℃ and 0.1 C rate.These electrochemical properties are better than other PCL-based allsolid-lithium batteries,and validate the concept of "polymer-in-ceramic" by avoiding the drawback of lower conductivity in prior "polymer-in-ceramic" electrolyte at high concentration of the ceramic.
文摘A kind of highly fluorinated bisphenol monomer was synthesized. It was characterized by FTIR, 1H NMR and MS. 6F PEEK and 6F PEEKK were prepared via aromatic nucleophilic substitution, based on [3,5 di(trifluoromethyl)] phenylhydroquinone and difluoro monomers. The T gs of 6F PEEK and 6F PEEKK are 423 and 436 K, respectively. The 6F polymers exhibit a high thermal stability and good solubility. The flexible, creasable and transparent thin films were easily obtained by compression moulding and solution casting.
文摘A novel crosslinkable fluorinated poly(ether ether ketone) with acetylenylbenzene end groups was prepared by solution condensation. The chemical structure of such polymer was confirmed by FTIR and 1H NMR. The crosslinking behavior and thermal stability were investigated by DSC and TGA respectively. The DSC thermogram for the first heating run shows a glass transition of 6F-PEEK at about 395 K and a exothermic peak correspongding to the self-crosslinking reaction of fluorinated poly(ether ether ketong) at about 700 K. For the second heating run, the exothermic peak disappered and the glass transition shifted to a higher temperature. The crosslinked polymer shown excelent thermal stability and solvent-resistence. The temperature for 5% weight loss was 774 K and the self-crosslinked polymer was no more disolved by polar solvents, which disolved in before crosslinking, such as DMF, DMAc and NMP. This kind of polymer may be a potential material used as electro-optical devices.
文摘The crosslinkable trifluoromethylated poly(aryl ethers) terminated with phenylethynyl moieties(11F-PAE-PEP)s were prepared in two step syntheses. The structure of 11F-PAE-PEP was confirmed by FTIR and 1H NMR. The crosslinking behavior was studied by DSC. There is a remarkable increase of T g after crosslinking of the poly(aryl ethers). The T g values of crosslinked polymers were 437 and 446 K, respectively. The crosslinked polymers could not be soluble in common organic solvents, such as N,N-dimethylformamide, N,N-dimethylacetamide, N-methyl-2-pyrrolidinone, chloroform, and tetrahydrofuran. The temperatures at a 5% mass loss of the crosslinked polymers in air were above 789 K. They showed a good optical property, too. This kind of polymers will be the promising materials used as the microelectronics and optical waveguide devices.
文摘A kind of high Fluorine-containing poly(aryl ether) without side reaction was synthesized in a two-step synthesis. Its structure was confirmed by FTIR, 1H NMR and 19F NMR. The polymer shows an excellent thermal stability, good solubility, low water absorption, low dielectric constant and low refractive index. Flexible and transparant thin film can be easily obtained by compression moulding or solution casting. The polymer would be a promising material used for microelectronics and waveguide devices.
文摘A novel bifluoro-monomer containing naphthalene moieties was synthesized and characterized by using FTIR, MS and NMR. Different poly(aryl ether ketone)s based on 1,4-bis(4,4′-fluorobenzoyl) naphthalene were prepared via aromatic nucleophilic substitution reaction. The polymers with a high molecular weight can be readily obtained due to the highly activity of the used monomer. 3F-PEEK-nK and 6F-PEEK-nK polymers were determined to exhibit good thermal stabilities with high T-g of 450 K and 457 K, respectively. Moreover, these polymers show a satisfactory solubility and can be cast into flexible and transparent films.
文摘The novel and soluble poly(ether ether ketone)(PEEK)containing fluorin structure(6F-PEEK)was prepared by nucleophilic reaction of 4,4’-difluorobenzophenone,bisphenol A and hexafluobisphenol A in the presence of anhydrous K2CO3 with tetramethylene sulfone as the solvents.The molecular weight of the polymer was determined by GPC.The structure of the polymer was characterized by FTIR,1H NMR and 19F NMR spectroscopies.The glass transition temperature and the temperature for 5% mass loss of 6F-PEEK were 153 and 493 ℃,respectively.The polymer exhibits an excellent thermal stability,mechanical property and solubility.The rate of elongation at break,tensile strength and tensile modulus of 6F-PEEK were 55.2%,66 MPa,and 2.13 GPa,respectively.
