Acid loss and plasticization of phosphoric acid(PA)-doped high-temperature polymer electrolyte membranes(HT-PEMs)are critical limitations to their practical application in fuel cells.To overcome these barriers,poly(te...Acid loss and plasticization of phosphoric acid(PA)-doped high-temperature polymer electrolyte membranes(HT-PEMs)are critical limitations to their practical application in fuel cells.To overcome these barriers,poly(terphenyl piperidinium)s constructed from the m-and p-isomers of terphenyl were synthesized to regulate the microstructure of the membrane.Highly rigid p-terphenyl units prompt the formation of moderate PA aggregates,where the ion-pair interaction between piperidinium and biphosphate is reinforced,leading to a reduction in the plasticizing effect.As a result,there are trade-offs between the proton conductivity,mechanical strength,and PA retention of the membranes with varied m/p-isomer ratios.The designed PA-doped PTP-20m membrane exhibits superior ionic conductivity,good mechanical strength,and excellent PA retention over a wide range of temperature(80–160°C)as well as satisfactory resistance to harsh accelerated aging tests.As a result,the membrane presents a desirable combination of performance(1.462 W cm^(-2) under the H_(2)/O_(2)condition,which is 1.5 times higher than that of PBI-based membrane)and durability(300 h at 160°C and 0.2 A cm^(-2))in the fuel cell.The results of this study provide new insights that will guide molecular design from the perspective of microstructure to improve the performance and robustness of HT-PEMs.展开更多
The molecular recyclability of poly (ethylene terephthalate) (PET) and three semi-aromatic polyesters poly (phloretic acid) (poly-H), poly (dihydroferulic acid) (poly-G), and poly (dihydrosinapinic acid) (poly-S) is e...The molecular recyclability of poly (ethylene terephthalate) (PET) and three semi-aromatic polyesters poly (phloretic acid) (poly-H), poly (dihydroferulic acid) (poly-G), and poly (dihydrosinapinic acid) (poly-S) is evaluated in this study. PET is an extensively used aromatic polyester, and poly-H, poly-G, and poly-S can be considered semi-aromatic poly (lactic acid) modifications. All these polyesters have been depolymerized at neutral pH and by acid- and base-catalyzed hydrolysis at two temperatures, i.e., 50˚C and 80˚C. Base-catalyzed depolymerization of virgin PET leads to an isolated yield of 38% after 48 hours of reaction at 80˚C. Contrary to these results for PET, almost all the monomers of the semi-aromatic polyesters poly-H, poly-G, and poly-S are recovered with isolated yields larger than 90% at the same temperature after 15 minutes in a facile manner. A shrinking particle model used to determine the global kinetics of the base-catalyzed depolymerization showed that the rate rises with increasing temperature. Using the shrinking particle model, the intrinsic reaction rate constants were determined. It has been demonstrated that the rate coefficients of the depolymerization of the semi-aromatic polyesters poly-H, poly-G, and poly-S are between 2 and 3 orders of magnitude higher than those for PET.展开更多
Graphene oxide(GO)is regarded as a promising candidate to construct solar absorbers for addressing freshwater crisis,but the easy delamination of GO in water poses a critical challenge for practical solar desalination...Graphene oxide(GO)is regarded as a promising candidate to construct solar absorbers for addressing freshwater crisis,but the easy delamination of GO in water poses a critical challenge for practical solar desalination.Herein,we improve the stability of GO membranes by a self-crosslinking poly(ionic liquid)(PIL)in a mild condition,which crosslinks neighbouring GO nanosheets without blemishing the hydrophilic structure of GO.By further adding carbon nanotubes(CNTs),the sandwiched GO/CNT@PIL(GCP)membrane displays a good stability in pH=1 or 13 solution even for 270 days.The molecular dynamics simulation results indicate that the generation of water nanofluidics in nanochannels of GO nanosheets remarkably reduces the water evaporation enthalpy in GCP membrane,compared to bulk water.Consequently,the GCP membrane exhibits a high evaporation rate(1.87 kg m^(-2)h^(-1))and displays stable evaporation rates for 14 h under 1 kW m^(-2)irradiation.The GCP membrane additionally works very well when using different water sources(e.g.,dye-polluted water)or even strong acidic solution(pH=1)or basic solution(pH=13).More importantly,through bundling pluralities of GCP membrane,an efficient solar desalination device is developed to produce drinkable water from seawater.The average daily drinkable water amount in sunny day is 10.1 kg m^(-2),which meets with the daily drinkable water needs of five adults.The high evaporation rate,long-time durability and good scalability make the GCP membrane an outstanding candidate for practical solar seawater desalination.展开更多
Functional multiblock poly(ether-b-amide)(PEBA)copolymers,comprised of PA1212(polyamide 1212)as hard segments and Jeffamine ED-2003 as soft segments,were successfully prepared via two-step melt polycondensation withou...Functional multiblock poly(ether-b-amide)(PEBA)copolymers,comprised of PA1212(polyamide 1212)as hard segments and Jeffamine ED-2003 as soft segments,were successfully prepared via two-step melt polycondensation without any amidation catalyst.Here,using diamino-terminated poly(propylene oxide)-poly(ethylene oxide)-poly(propylene oxide)(PPO-PEO-PPO),Jeffamine ED-2003,enhances the compatibility between polyamide oligomer and polyether,which is better than the traditional route using hydroxyl-terminated polyether.The chemical structure of multiblock PEBAs,as well as the microphase separated structure with crystalline phase of polyamide and polyether,were confirmed by heteronuclear multiple-bond correlation spectrum,heteronuclear multiple quantum correlation spectrum,Fourier transform infrared spectroscopy(FT-IR),differential scanning calorimetry and dynamic mechanical analysis.The hydrophilic PEBA copolymers showed water adsorption ranging from 87.3%to 17.1%depending on the polyether content,and specially showed moisture responsive behavior within seconds when exposed to moisture.The corresponding mechanism was studied using time-resolved attenuated total reflectance FT-IR spectroscopy in the molecular level and the water diffusion coefficient was estimated to be 1.07×10^(–8)cm^(2)∙s^(-1).Two-dimensional correlation FT-IR spectra analysis was performed to confirm that the interaction between water and polyether phase was in preference to that between water and polyamide matrix,and water molecule only forms hydrogen bond with the polyether segment.Due to the incorporation of PEO segments,the PEBAs have the surface resistivity varying from 5.6×10^(9)to 6.5×10^(10)Ω,which makes PEBA potential candidate as permanent antistatic agent.展开更多
Polyelectrolytes are charged polymers comprising macromolecules in which substantial portions of the constituent units contain cationic(e.g.,pyridinium,ammonium)or anionic(e.g.,sulfonate,carboxylate)groups,which posse...Polyelectrolytes are charged polymers comprising macromolecules in which substantial portions of the constituent units contain cationic(e.g.,pyridinium,ammonium)or anionic(e.g.,sulfonate,carboxylate)groups,which possess special functions from the features of counterions,such as dissociation to charged species,mechanical stability,phase behavior,etc.Therefore,functional polyelectrolytes have been widely applied in many fields.In this perspective,we present some progresses in the studies of poly(polyoxometalate)s,denoted as poly(POM)s,as a kind of new charged polymers/polyelectrolytes,by covalent bonding between the inorganic polyoxometalate(POM)clusters and the organic polymer chains.According to the distinct positions of POMs in polymer chain and functions of poly(POM)s,they are divided into the following four categories:crosslinked poly(POM);side-chain poly(POM);backbone poly(POM),including poly(POM)-conjugated polymer hybrid and block poly(POM)-polymer;and POM-based covalent organic framework(PCOF).This perspective introduces the synthesis methods of poly(POM)polyelectrolytes and their macromolecular and aggregate structural characteristics,while also focusing on their properties and functions.Their application areas include catalysis,thermal resistance,optical functions,fuel cells and batteries,etc.展开更多
Polyoxometalates(POMs)are classified as solid superacids which can exhibit notable proton conductivity,making them a promising functional inorganic filler for enhancing the proton conductivity of proton exchange membr...Polyoxometalates(POMs)are classified as solid superacids which can exhibit notable proton conductivity,making them a promising functional inorganic filler for enhancing the proton conductivity of proton exchange membranes(PEMs).In this study,a series of hybrid membranes were obtained by molecular-level hybridization of Weakley-type POM Na_(7)H_(2)LaW_(10)O_(36)(LaW_(10))clusters into sulfonated poly(aryl ether ketone sulfone)(SPAEKS).All hybrid membranes exhibited greater proton conductivity than the pristine membrane in the 30–80℃temperature range.When the doping amount of LaW 10 reached 7 wt.%,the proton conductivity of M-LaW 10^(-7)achieved 64 mS·cm^(−1)at 80℃.Lanthanide ions'high coordination number property and variable coordination environment can aid to attract more water molecules from the environment.LaW 10 and these bound water can construct denser hydrogen bonds with–SO_(3)H of SPAEKS.These intensive hydrogen bonds will facilitate the constitution of more continuous proton transport channels,and improve the proton conductivity of the hybrid membrane.This work off ers a fresh approach to using POMs containing rare-earth components in PEMs.展开更多
A series of novel poly(aryl ether nitrile)s containing phthalazinone moiety were synthesized by the nucleophilic displacement reaction of bisphenol-like monomers (I) with 2,6-difluorobenzonitrile. The inherent vis...A series of novel poly(aryl ether nitrile)s containing phthalazinone moiety were synthesized by the nucleophilic displacement reaction of bisphenol-like monomers (I) with 2,6-difluorobenzonitrile. The inherent viscosities ranged from 0.46 to 1.07 dL g^-1. The glass transition temperatures were in the range of 277-295℃, and the temperatures for 10% weight loss in nitrogen atmosphere were found between 495 and 527 ℃. The structures of these resultant polymers were confirmed by FT-IR and 1^H NMR. Moreover, the properties of poly(aryl ether nitrile)s including solubility and crystallinity were also studied.展开更多
Two novel heterocyclic diamine monomers: 1,2-dihydro-2-(4-aminophenyl)-4-[4-(4-aminophenoxy)phenyl] (2H)phthalazin-1-one and 1,2-dihydro-2-(4-aminophenyl)-4-[4-(4-aminophenoxy)-3,5-dimethylphenyl](2H)phthalazin-1-one ...Two novel heterocyclic diamine monomers: 1,2-dihydro-2-(4-aminophenyl)-4-[4-(4-aminophenoxy)phenyl] (2H)phthalazin-1-one and 1,2-dihydro-2-(4-aminophenyl)-4-[4-(4-aminophenoxy)-3,5-dimethylphenyl](2H)phthalazin-1-one were successfully synthesized from readily available heterocyclic bisphenol-like monomers in two steps in high yield. A series of novel poly(aryl ether amide)s containing the phthalazinone moiety were successfully prepared by the direct polymerization of the novel diamines and aromatic dicarboxylic acids using triphenyl phosphite and pyridine as condensing agents.展开更多
A series of new hyperbranched poly(aryleneethynylene)s are synthesized by the copolycyclotrimerizations oftetraynes(Ⅰand Ⅱ)with aliphatic monoynes(A-C)catalyzed by tantalum-,niobium-,and cobalt-based catalysts.All t...A series of new hyperbranched poly(aryleneethynylene)s are synthesized by the copolycyclotrimerizations oftetraynes(Ⅰand Ⅱ)with aliphatic monoynes(A-C)catalyzed by tantalum-,niobium-,and cobalt-based catalysts.All thereactions proceed smoothly and soluble polymers of high molecular weights(M_w up to 3.8×10~4)are obtained in high yields(up to 97%).展开更多
The improvement of biocompatibility of polyurethanes was investigated.The results demonstrate that the blood compatibility of polyurethanes can be further improved by just simply mixing with the fluorinated phosphatid...The improvement of biocompatibility of polyurethanes was investigated.The results demonstrate that the blood compatibility of polyurethanes can be further improved by just simply mixing with the fluorinated phosphatidylcholine poly(carbonate urethane)s(FPCPCUs).The solution blending was done by mixing poly(ether urethane)(PEU)with FPCPCU in different compositions.An increased blood compatibility of the blend films was observed with the increase of FPCPCU content,and when FPCPCU content reached to 40 wt%(40F...展开更多
Three novel poly(ether imide)s were synthesized by one-step solution polymerization from 2-(3, 4-dicarboxyl-N-phenyl)-4-(3, 4-dicarboxyl-phenoxyl-4-(2-methyl)-phenyl)-2, 3- phthal-azin-1-one dianhydride and three amin...Three novel poly(ether imide)s were synthesized by one-step solution polymerization from 2-(3, 4-dicarboxyl-N-phenyl)-4-(3, 4-dicarboxyl-phenoxyl-4-(2-methyl)-phenyl)-2, 3- phthal-azin-1-one dianhydride and three amines, and characterized. The polymers show good solubility and thermal properties.展开更多
Acidic poly(ionic liquid)s(PILs)with swelling ability were synthesized by free radical copolymerization of N-vinylimidazolium ionic liquids,divinylbenzene(DVB)and sodium acrylate(NaAA),and further acidification by sul...Acidic poly(ionic liquid)s(PILs)with swelling ability were synthesized by free radical copolymerization of N-vinylimidazolium ionic liquids,divinylbenzene(DVB)and sodium acrylate(NaAA),and further acidification by sulfuric acid.The swelling ability of acidic PILs was greatly affected by cross-linker content and chain length of 3-alkyl-substituents on imidazolium.Cross-linked network structures could be observed from the cryogenic scanning electron microscopy(cryo-SEM)images of the swollen acidic PILs in formic acid.Acidic PILs with network structures in swollen state exhibited excellent activities in the esterification of cyclohexene and formic acid,and the catalytic activities were in positive correlation with their swelling abilities.Acidic PIL with 3-octyl-substituent and 2.5 mol%DVB(PIL-C8-2.5DVB-HSO4)had the highest swelling ability in formic acid and exhibited comparable catalytic activities with homogeneous catalysts such as sulfuric acid and p-toluenesulfonic acid.展开更多
A series of aliphatic biodegradable poly(ether-ester)s based on poly(butylene succinate)(PBS)as hard segment and poly(tetramethylene oxide)(PTMO,M_n=1 000 g/mol) as soft segment were synthesized.The composit...A series of aliphatic biodegradable poly(ether-ester)s based on poly(butylene succinate)(PBS)as hard segment and poly(tetramethylene oxide)(PTMO,M_n=1 000 g/mol) as soft segment were synthesized.The composition dependence of thermal behavior,morphology and mechanical properties was investigated by differential scanning calorimetry(DSC),atomic force microscopy(AFM),and tensile testing.The crystallization temperature(T_c) and melting temperature(T_m) of the PBS block within poly(ether-ester)s decrease steadily at first,but decrease sharply with PTMO content above 50 wt%.Two crystallization peaks were detected for PTMO in PBSPTMO60 sample,suggesting the occurrence of fractionated crystallization.The crystallization enthalpies(△H_c) and melting enthalpies(△H_m) of PBS block decrease at first,then increase as PTMO content increases further.AFM has demonstrated that phase-separated morphology transforms from a phase of continuous hard matrix to one of continuous soft matrix containing isolated hard domain as PTMO content is increased.Finally,the results of tensile testing show that the poly(ether-ester)s present the behavior of plastics when PTMO content is below 40 wt%,and of thermoplastic elastomers with PTMO content above 50 wt%.By varying the composition of copolymer,the aliphatic poly(ether-ester)s plastics,or especially biodegradable aliphatic poly(ether-ester)s thermoplastic elastomers can be obtained.展开更多
A novel sulfonated poly(arylene ether) containing triphenylmethane moieties was synthesized by the sulfonation of a designed parent polymer using chlorosulfonic acid as sulfonation agent. The sulfonation took place ...A novel sulfonated poly(arylene ether) containing triphenylmethane moieties was synthesized by the sulfonation of a designed parent polymer using chlorosulfonic acid as sulfonation agent. The sulfonation took place at the para position of the pendant phenyl rings because of the specially designed parent polymer. The position and degree of sulfonation were characterized by ^1H-NMR and elemental analysis. The sulfonated polymers are highly soluble in common organic solvents, such as dimethylsulfoxide, N,N'-dimethylacetamide, dimethylformamide, ethylene glycol monomethyl ether, and can be readily cast into tough and smooth films from solutions. The films showed good thermal and hydrolysis stabilities. Moreover, Fenton's reagent test revealed that the films exhibited superior stability to oxidation. The proton conductivities of the films were comparable with Nation 117 under same conditions. The membrane electrode assembly (MEA) prepared with the asmade film (706 EW, 100 μm dry thickness) shows better cell performance than Nation 115-MEA in the whole current density range.展开更多
A novel AB3-type monomer was prepared from gallic acid and DL-2-aminobutyric acid, and used for the synthesis of the biocompatible hyperbranched poly(ester-amide)s by self-polycondensation. The polymers were character...A novel AB3-type monomer was prepared from gallic acid and DL-2-aminobutyric acid, and used for the synthesis of the biocompatible hyperbranched poly(ester-amide)s by self-polycondensation. The polymers were characterized via FTIR and NMR spectroscopy and thermal analysis, and the average degree of branching of the polymers was estimated to be 0.75. The polymers with abundant acetyl end groups were found to be amorphous with lower intrinsic viscosity, better thermal stability and excellent solubility.展开更多
Guanidinylated bioresponsive poly(amido amine)s polymers, CAR-CBA and CHL-CBA, weresynthesized by Michael-type addition reaction between guanidine hydrochloride(CAR) orchlorhexidine(CHL) and N,N-cystaminebisacrylamide...Guanidinylated bioresponsive poly(amido amine)s polymers, CAR-CBA and CHL-CBA, weresynthesized by Michael-type addition reaction between guanidine hydrochloride(CAR) orchlorhexidine(CHL) and N,N-cystaminebisacrylamide(CBA). Previous studies have shownthat both polymers had high transfection efficiencies as gene delivery carriers. In this study,we investigated the nucleolus localization abilities and cellular internalization pathways ofthese two polymers in gene delivery. Each polymer condensed plasmid DNA(p DNA) andformed nanoparticle complexes, and then their transfection studies were performed inMCF-7 cells. Both complexes were found enriched in nucleolus after cellular transfection,and their transfection efficiencies were significantly improved when transfection was per-formed on MCF-7 cells arrested at M phase. The transfection efficiency of CAR-CBA-pDNAwas inhibited by chlorpromazine, and cell endosomes were disrupted after being exposedto CAR-CBA-pDNA. In regards to CHL-CBA-pDNA, its transfection efficiency was not affected by three types of endocytosis inhibitors used in the study, and CHL-CBA-pDNA showed no effect on endosomes. Cellular lactate dehydrogenase release and membrane morphology were changed after cells were transfected by the two complexes. The results indicated that both CAR-CBA and CHL-CBA polymers demonstrated good nucleolus localization abilities. It was beneficial for transfection when cells were arrested at M phase. CAR-CBA-pDNA cellular internalization was involved with clathrin-mediated endocytosis pathway, and escaping from endosomal entrapment, while the cellular uptake of CHL-CBA-pDNA occurs via clathrin-and caveolae-independent mechanism.展开更多
基金supported by The National Key Research and Development Program of China(2021YFB4001204)National Natural Science Foundation of China(22379143)。
文摘Acid loss and plasticization of phosphoric acid(PA)-doped high-temperature polymer electrolyte membranes(HT-PEMs)are critical limitations to their practical application in fuel cells.To overcome these barriers,poly(terphenyl piperidinium)s constructed from the m-and p-isomers of terphenyl were synthesized to regulate the microstructure of the membrane.Highly rigid p-terphenyl units prompt the formation of moderate PA aggregates,where the ion-pair interaction between piperidinium and biphosphate is reinforced,leading to a reduction in the plasticizing effect.As a result,there are trade-offs between the proton conductivity,mechanical strength,and PA retention of the membranes with varied m/p-isomer ratios.The designed PA-doped PTP-20m membrane exhibits superior ionic conductivity,good mechanical strength,and excellent PA retention over a wide range of temperature(80–160°C)as well as satisfactory resistance to harsh accelerated aging tests.As a result,the membrane presents a desirable combination of performance(1.462 W cm^(-2) under the H_(2)/O_(2)condition,which is 1.5 times higher than that of PBI-based membrane)and durability(300 h at 160°C and 0.2 A cm^(-2))in the fuel cell.The results of this study provide new insights that will guide molecular design from the perspective of microstructure to improve the performance and robustness of HT-PEMs.
文摘The molecular recyclability of poly (ethylene terephthalate) (PET) and three semi-aromatic polyesters poly (phloretic acid) (poly-H), poly (dihydroferulic acid) (poly-G), and poly (dihydrosinapinic acid) (poly-S) is evaluated in this study. PET is an extensively used aromatic polyester, and poly-H, poly-G, and poly-S can be considered semi-aromatic poly (lactic acid) modifications. All these polyesters have been depolymerized at neutral pH and by acid- and base-catalyzed hydrolysis at two temperatures, i.e., 50˚C and 80˚C. Base-catalyzed depolymerization of virgin PET leads to an isolated yield of 38% after 48 hours of reaction at 80˚C. Contrary to these results for PET, almost all the monomers of the semi-aromatic polyesters poly-H, poly-G, and poly-S are recovered with isolated yields larger than 90% at the same temperature after 15 minutes in a facile manner. A shrinking particle model used to determine the global kinetics of the base-catalyzed depolymerization showed that the rate rises with increasing temperature. Using the shrinking particle model, the intrinsic reaction rate constants were determined. It has been demonstrated that the rate coefficients of the depolymerization of the semi-aromatic polyesters poly-H, poly-G, and poly-S are between 2 and 3 orders of magnitude higher than those for PET.
基金the financial support of the National Key R&D Program of China(No.2019YFC1806000)the Huazhong University of Science and Technology(No.3004013118)+2 种基金support from the National Natural Science Foundation of China(No.51903099)Huazhong University of Science and Technology(No.3004013134)the 100 Talents Program of the Hubei Provincial Government.Z.D.thanks the Postdoctoral Science Foundation of China(No.0106013063).
文摘Graphene oxide(GO)is regarded as a promising candidate to construct solar absorbers for addressing freshwater crisis,but the easy delamination of GO in water poses a critical challenge for practical solar desalination.Herein,we improve the stability of GO membranes by a self-crosslinking poly(ionic liquid)(PIL)in a mild condition,which crosslinks neighbouring GO nanosheets without blemishing the hydrophilic structure of GO.By further adding carbon nanotubes(CNTs),the sandwiched GO/CNT@PIL(GCP)membrane displays a good stability in pH=1 or 13 solution even for 270 days.The molecular dynamics simulation results indicate that the generation of water nanofluidics in nanochannels of GO nanosheets remarkably reduces the water evaporation enthalpy in GCP membrane,compared to bulk water.Consequently,the GCP membrane exhibits a high evaporation rate(1.87 kg m^(-2)h^(-1))and displays stable evaporation rates for 14 h under 1 kW m^(-2)irradiation.The GCP membrane additionally works very well when using different water sources(e.g.,dye-polluted water)or even strong acidic solution(pH=1)or basic solution(pH=13).More importantly,through bundling pluralities of GCP membrane,an efficient solar desalination device is developed to produce drinkable water from seawater.The average daily drinkable water amount in sunny day is 10.1 kg m^(-2),which meets with the daily drinkable water needs of five adults.The high evaporation rate,long-time durability and good scalability make the GCP membrane an outstanding candidate for practical solar seawater desalination.
基金financially supported by the National Natural Science Foundation of China (21978089 and 21878256)the Fundamental Research Funds for the Central Universities (22221818010)+1 种基金the 111 Project (B20031)the Program of Shanghai Subject Chief Scientist (21XD1433000)
文摘Functional multiblock poly(ether-b-amide)(PEBA)copolymers,comprised of PA1212(polyamide 1212)as hard segments and Jeffamine ED-2003 as soft segments,were successfully prepared via two-step melt polycondensation without any amidation catalyst.Here,using diamino-terminated poly(propylene oxide)-poly(ethylene oxide)-poly(propylene oxide)(PPO-PEO-PPO),Jeffamine ED-2003,enhances the compatibility between polyamide oligomer and polyether,which is better than the traditional route using hydroxyl-terminated polyether.The chemical structure of multiblock PEBAs,as well as the microphase separated structure with crystalline phase of polyamide and polyether,were confirmed by heteronuclear multiple-bond correlation spectrum,heteronuclear multiple quantum correlation spectrum,Fourier transform infrared spectroscopy(FT-IR),differential scanning calorimetry and dynamic mechanical analysis.The hydrophilic PEBA copolymers showed water adsorption ranging from 87.3%to 17.1%depending on the polyether content,and specially showed moisture responsive behavior within seconds when exposed to moisture.The corresponding mechanism was studied using time-resolved attenuated total reflectance FT-IR spectroscopy in the molecular level and the water diffusion coefficient was estimated to be 1.07×10^(–8)cm^(2)∙s^(-1).Two-dimensional correlation FT-IR spectra analysis was performed to confirm that the interaction between water and polyether phase was in preference to that between water and polyamide matrix,and water molecule only forms hydrogen bond with the polyether segment.Due to the incorporation of PEO segments,the PEBAs have the surface resistivity varying from 5.6×10^(9)to 6.5×10^(10)Ω,which makes PEBA potential candidate as permanent antistatic agent.
基金supported by the Natural Science Foundation of Shandong Province of China(No.ZR2023QB278)the National Natural Science Foundation of China(No.92061120).
文摘Polyelectrolytes are charged polymers comprising macromolecules in which substantial portions of the constituent units contain cationic(e.g.,pyridinium,ammonium)or anionic(e.g.,sulfonate,carboxylate)groups,which possess special functions from the features of counterions,such as dissociation to charged species,mechanical stability,phase behavior,etc.Therefore,functional polyelectrolytes have been widely applied in many fields.In this perspective,we present some progresses in the studies of poly(polyoxometalate)s,denoted as poly(POM)s,as a kind of new charged polymers/polyelectrolytes,by covalent bonding between the inorganic polyoxometalate(POM)clusters and the organic polymer chains.According to the distinct positions of POMs in polymer chain and functions of poly(POM)s,they are divided into the following four categories:crosslinked poly(POM);side-chain poly(POM);backbone poly(POM),including poly(POM)-conjugated polymer hybrid and block poly(POM)-polymer;and POM-based covalent organic framework(PCOF).This perspective introduces the synthesis methods of poly(POM)polyelectrolytes and their macromolecular and aggregate structural characteristics,while also focusing on their properties and functions.Their application areas include catalysis,thermal resistance,optical functions,fuel cells and batteries,etc.
基金financially supported by the National Natural Science Foundation of China(No.22271022)the Natural Science Foundation of Jilin Province(No.YDZJ202201ZYTS342)supported by the China Scholarship Council(CSC No.201802335014).
文摘Polyoxometalates(POMs)are classified as solid superacids which can exhibit notable proton conductivity,making them a promising functional inorganic filler for enhancing the proton conductivity of proton exchange membranes(PEMs).In this study,a series of hybrid membranes were obtained by molecular-level hybridization of Weakley-type POM Na_(7)H_(2)LaW_(10)O_(36)(LaW_(10))clusters into sulfonated poly(aryl ether ketone sulfone)(SPAEKS).All hybrid membranes exhibited greater proton conductivity than the pristine membrane in the 30–80℃temperature range.When the doping amount of LaW 10 reached 7 wt.%,the proton conductivity of M-LaW 10^(-7)achieved 64 mS·cm^(−1)at 80℃.Lanthanide ions'high coordination number property and variable coordination environment can aid to attract more water molecules from the environment.LaW 10 and these bound water can construct denser hydrogen bonds with–SO_(3)H of SPAEKS.These intensive hydrogen bonds will facilitate the constitution of more continuous proton transport channels,and improve the proton conductivity of the hybrid membrane.This work off ers a fresh approach to using POMs containing rare-earth components in PEMs.
文摘A series of novel poly(aryl ether nitrile)s containing phthalazinone moiety were synthesized by the nucleophilic displacement reaction of bisphenol-like monomers (I) with 2,6-difluorobenzonitrile. The inherent viscosities ranged from 0.46 to 1.07 dL g^-1. The glass transition temperatures were in the range of 277-295℃, and the temperatures for 10% weight loss in nitrogen atmosphere were found between 495 and 527 ℃. The structures of these resultant polymers were confirmed by FT-IR and 1^H NMR. Moreover, the properties of poly(aryl ether nitrile)s including solubility and crystallinity were also studied.
文摘Two novel heterocyclic diamine monomers: 1,2-dihydro-2-(4-aminophenyl)-4-[4-(4-aminophenoxy)phenyl] (2H)phthalazin-1-one and 1,2-dihydro-2-(4-aminophenyl)-4-[4-(4-aminophenoxy)-3,5-dimethylphenyl](2H)phthalazin-1-one were successfully synthesized from readily available heterocyclic bisphenol-like monomers in two steps in high yield. A series of novel poly(aryl ether amide)s containing the phthalazinone moiety were successfully prepared by the direct polymerization of the novel diamines and aromatic dicarboxylic acids using triphenyl phosphite and pyridine as condensing agents.
基金This project was supported by the Research Grants Council of Hong Kong(Nos.603304,604903HKUST6085/02P).
文摘A series of new hyperbranched poly(aryleneethynylene)s are synthesized by the copolycyclotrimerizations oftetraynes(Ⅰand Ⅱ)with aliphatic monoynes(A-C)catalyzed by tantalum-,niobium-,and cobalt-based catalysts.All thereactions proceed smoothly and soluble polymers of high molecular weights(M_w up to 3.8×10~4)are obtained in high yields(up to 97%).
基金This work was financially supported by the National Natural Science Foundation of China(Nos.50673063 and 50533050)Young Foundation of Sichuan University for Financial Support.This work was also subsidized by the Special Funds for Major State Basic Research Projects of China(No.2003CB615600).
文摘The improvement of biocompatibility of polyurethanes was investigated.The results demonstrate that the blood compatibility of polyurethanes can be further improved by just simply mixing with the fluorinated phosphatidylcholine poly(carbonate urethane)s(FPCPCUs).The solution blending was done by mixing poly(ether urethane)(PEU)with FPCPCU in different compositions.An increased blood compatibility of the blend films was observed with the increase of FPCPCU content,and when FPCPCU content reached to 40 wt%(40F...
基金This work was sponsored by the National Natural Science Foundation of China (No. 59473901).
文摘Three novel poly(ether imide)s were synthesized by one-step solution polymerization from 2-(3, 4-dicarboxyl-N-phenyl)-4-(3, 4-dicarboxyl-phenoxyl-4-(2-methyl)-phenyl)-2, 3- phthal-azin-1-one dianhydride and three amines, and characterized. The polymers show good solubility and thermal properties.
基金This work was supported by the National Natural Science Foundation of China(21773068,21811530273,21573072)the National Key Research and Development Program of China(2017YFA0403102)Shanghai Leading Academic Discipline Project(B409).
文摘Acidic poly(ionic liquid)s(PILs)with swelling ability were synthesized by free radical copolymerization of N-vinylimidazolium ionic liquids,divinylbenzene(DVB)and sodium acrylate(NaAA),and further acidification by sulfuric acid.The swelling ability of acidic PILs was greatly affected by cross-linker content and chain length of 3-alkyl-substituents on imidazolium.Cross-linked network structures could be observed from the cryogenic scanning electron microscopy(cryo-SEM)images of the swollen acidic PILs in formic acid.Acidic PILs with network structures in swollen state exhibited excellent activities in the esterification of cyclohexene and formic acid,and the catalytic activities were in positive correlation with their swelling abilities.Acidic PIL with 3-octyl-substituent and 2.5 mol%DVB(PIL-C8-2.5DVB-HSO4)had the highest swelling ability in formic acid and exhibited comparable catalytic activities with homogeneous catalysts such as sulfuric acid and p-toluenesulfonic acid.
基金Funded by the National Natural Science Foundation of China(No.50873071)the Teaching and Research Award Program for Outstanding Young Professors in Higher Education Institute,MOE,China
文摘A series of aliphatic biodegradable poly(ether-ester)s based on poly(butylene succinate)(PBS)as hard segment and poly(tetramethylene oxide)(PTMO,M_n=1 000 g/mol) as soft segment were synthesized.The composition dependence of thermal behavior,morphology and mechanical properties was investigated by differential scanning calorimetry(DSC),atomic force microscopy(AFM),and tensile testing.The crystallization temperature(T_c) and melting temperature(T_m) of the PBS block within poly(ether-ester)s decrease steadily at first,but decrease sharply with PTMO content above 50 wt%.Two crystallization peaks were detected for PTMO in PBSPTMO60 sample,suggesting the occurrence of fractionated crystallization.The crystallization enthalpies(△H_c) and melting enthalpies(△H_m) of PBS block decrease at first,then increase as PTMO content increases further.AFM has demonstrated that phase-separated morphology transforms from a phase of continuous hard matrix to one of continuous soft matrix containing isolated hard domain as PTMO content is increased.Finally,the results of tensile testing show that the poly(ether-ester)s present the behavior of plastics when PTMO content is below 40 wt%,and of thermoplastic elastomers with PTMO content above 50 wt%.By varying the composition of copolymer,the aliphatic poly(ether-ester)s plastics,or especially biodegradable aliphatic poly(ether-ester)s thermoplastic elastomers can be obtained.
基金This work was financially supported by the National Science Foundation of China (NSFC) (Key project, No. 29734120)the China High-Tech Development 863 Program (No. 2003AA302410)+1 种基金Natural Science Foundation of Guangdong Province (Excellent Team Project, No. 015007)Canton Province Sci & Tech Bureau (Key Strategic Project, No. A1100402) and Guangzhou Sci & Tech Bureau
文摘A novel sulfonated poly(arylene ether) containing triphenylmethane moieties was synthesized by the sulfonation of a designed parent polymer using chlorosulfonic acid as sulfonation agent. The sulfonation took place at the para position of the pendant phenyl rings because of the specially designed parent polymer. The position and degree of sulfonation were characterized by ^1H-NMR and elemental analysis. The sulfonated polymers are highly soluble in common organic solvents, such as dimethylsulfoxide, N,N'-dimethylacetamide, dimethylformamide, ethylene glycol monomethyl ether, and can be readily cast into tough and smooth films from solutions. The films showed good thermal and hydrolysis stabilities. Moreover, Fenton's reagent test revealed that the films exhibited superior stability to oxidation. The proton conductivities of the films were comparable with Nation 117 under same conditions. The membrane electrode assembly (MEA) prepared with the asmade film (706 EW, 100 μm dry thickness) shows better cell performance than Nation 115-MEA in the whole current density range.
文摘A novel AB3-type monomer was prepared from gallic acid and DL-2-aminobutyric acid, and used for the synthesis of the biocompatible hyperbranched poly(ester-amide)s by self-polycondensation. The polymers were characterized via FTIR and NMR spectroscopy and thermal analysis, and the average degree of branching of the polymers was estimated to be 0.75. The polymers with abundant acetyl end groups were found to be amorphous with lower intrinsic viscosity, better thermal stability and excellent solubility.
基金supported by National Natural Science Foundation of China (Grant no. 81373335)
文摘Guanidinylated bioresponsive poly(amido amine)s polymers, CAR-CBA and CHL-CBA, weresynthesized by Michael-type addition reaction between guanidine hydrochloride(CAR) orchlorhexidine(CHL) and N,N-cystaminebisacrylamide(CBA). Previous studies have shownthat both polymers had high transfection efficiencies as gene delivery carriers. In this study,we investigated the nucleolus localization abilities and cellular internalization pathways ofthese two polymers in gene delivery. Each polymer condensed plasmid DNA(p DNA) andformed nanoparticle complexes, and then their transfection studies were performed inMCF-7 cells. Both complexes were found enriched in nucleolus after cellular transfection,and their transfection efficiencies were significantly improved when transfection was per-formed on MCF-7 cells arrested at M phase. The transfection efficiency of CAR-CBA-pDNAwas inhibited by chlorpromazine, and cell endosomes were disrupted after being exposedto CAR-CBA-pDNA. In regards to CHL-CBA-pDNA, its transfection efficiency was not affected by three types of endocytosis inhibitors used in the study, and CHL-CBA-pDNA showed no effect on endosomes. Cellular lactate dehydrogenase release and membrane morphology were changed after cells were transfected by the two complexes. The results indicated that both CAR-CBA and CHL-CBA polymers demonstrated good nucleolus localization abilities. It was beneficial for transfection when cells were arrested at M phase. CAR-CBA-pDNA cellular internalization was involved with clathrin-mediated endocytosis pathway, and escaping from endosomal entrapment, while the cellular uptake of CHL-CBA-pDNA occurs via clathrin-and caveolae-independent mechanism.