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Soil colloids can significantly enhance spreading of polybromodiphenyl ethers in groundwater by serving as an effective carrier 被引量:1
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作者 Lin Duan Min Li +1 位作者 Jiameng Liu Wei Chen 《Journal of Environmental Sciences》 2025年第1期93-100,共8页
Polybromodiphenyl ethers(PBDEs),the widely used flame retardants,are common contaminants in surface soils at e-waste recycling sites.The association of PBDEs with soil colloids has been observed,indicating the potenti... Polybromodiphenyl ethers(PBDEs),the widely used flame retardants,are common contaminants in surface soils at e-waste recycling sites.The association of PBDEs with soil colloids has been observed,indicating the potential risk to groundwater due to colloid-facilitated transport.However,the extent to which soil colloidsmay enhance the spreading of PBDEs in groundwater is largely unknown.Herein,we report the co-transport of decabromodiphenyl ester(BDE-209)and soil colloids in saturated porous media.The colloids released froma soil sample collected at an e-waste recycling site in Tianjin,China,contain high concentration of PBDEs,with BDE-209 being the most abundant conger(320±30 mg/kg).The colloids exhibit relatively high mobility in saturated sand columns,under conditions commonly observed in groundwater environments.Notably,under all the tested conditions(i.e.,varying flow velocity,pH,ionic species and ionic strength),the mass of eluted BDE-209 correlates linearly with that of eluted soil colloids,even though the mobility of the colloids varies markedly depending on the specific hydrodynamic and solution chemistry conditions involved.Additionally,the mass of BDE-209 retained in the columns also correlates strongly with themass of retained colloids.Apparently,the PBDEs remain bound to soil colloids during transport in porous media.Findings in this study indicate that soil colloidsmay significantly promote the transport of PBDEs in groundwater by serving as an effective carrier.This might be the reason why the highly insoluble and adsorptive PBDEs are found in groundwater at some PBDE-contaminated sites. 展开更多
关键词 polybromodiphenyl ethers Soil colloids E-waste recycling sites GROUNDWATER Facilitated transport
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Cyclic ethers-based solid electrolyte derived from in situ ring-opening polymerization strategy
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作者 Wubin Du Yong Wu +7 位作者 Hao Cheng Ran Bu Kang Shen Yuanzhong Tan Zhijun Wu Hongge Pan Yifan Wang Yingying Lu 《Green Energy & Environment》 2025年第7期1359-1376,共18页
Although solid-state polymer electrolytes(SPEs)are expected to solve the safety hazards and limited energy density in the energy storage systems,they still encounter an inferior electrode/electrolyte interface when pr... Although solid-state polymer electrolytes(SPEs)are expected to solve the safety hazards and limited energy density in the energy storage systems,they still encounter an inferior electrode/electrolyte interface when prepared in an ex situ manner.Recently,in situ polymerization of SPEs favor high interfacial infiltrability,improved interface contact,and reduced interface resistance,owing to the formation of a"superconformal"interface between electrode and electrolyte.Especially,in situ strategies employing ring-opening polymerization(ROP)are emerging as dazzling stars,further enabling moderate polymerization conditions,controllable molecular structure,and reduced interfacial side reaction.As the main monomers that can be in situ polymerized via the ROP strategy,cyclic ethers have been used to construct the CE-SPEs with many merits,including good battery electrochemical performances and a simple assembly process.Here,as a systematic summarization of the existing reports,this review focuses on the polymerization mechanism of ROP,the design principles of CE-SPEs electrolytes,and the recent application of in situ CE-SPEs.In particular,this review thoroughly discusses the selection of different cyclic monomers,initiators and various modification approaches in in situ fabricating CE-SPEs.Ending with offering future challenges and perspectives,this review envisions shedding light on the profound understanding and scientific guidance for further development of high-performance in situ CE-SPEs. 展开更多
关键词 Cyclic ethers Solid-state polymer electrolytes Ring-opening polymerization In situ polymerization
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Synthesis and characterization of quaternized poly(phthalazinone ether sulfone ketone)for anion-exchange membrane 被引量:9
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作者 Xi Gao Jian Chun Yan +3 位作者 Hua Min Zhang Shou Hai Zhang Cheng Liu Ping Zhao 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第10期1269-1272,共4页
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
关键词 CHLOROMETHYLATION QUATERNIZATION poly(phthalazinone ether sulfone ketone) Anion-exchange membrane Vanadium redox flowbattery
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UV-induced Self-initiated Graft Polymerization of Acrylamide onto Poly(ether ether ketone) 被引量:6
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作者 CHEN Rui-chao, SUN Hui, LI Ang and XU Guo-zhi College of Materials Science and Mechanical Engineering, National Center for Quality Supervision and Test of Plastic Products, Beijing Technology and Business University, Beijing 100048, P. R. China 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2012年第1期162-165,共4页
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
关键词 polyether ether ketone)(PEEK) UV-grafting Surface modification Self-initiation Graft polymerization
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Synthesis and Characterization of Poly(ether imide)s Containing m-Methyl and Phthalazinone Moieties 被引量:2
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作者 Jin Yan WANG Shu De XIAO Xi Gao JIAN 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第4期331-332,共2页
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
关键词 Synthesis poly(ether imide)s PHTHALAZINONE dianhydride.
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Synthesis and Adsorption Property of Two Polymeric Adsorbents with Pendent Ether Bonds 被引量:4
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作者 JianGouHUANG ManCaiXU +1 位作者 HaiTaoLI ZuoQingSHI 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第9期914-916,共3页
Two polymeric adsorbents, poly(methyl p-vinylbenzyl ether) and poly(phenyl p-vinylbenzyl ether), were synthesized from chloromethylated polystyrene. Their adsorption property for phenol in hexane solution was investig... Two polymeric adsorbents, poly(methyl p-vinylbenzyl ether) and poly(phenyl p-vinylbenzyl ether), were synthesized from chloromethylated polystyrene. Their adsorption property for phenol in hexane solution was investigated. The results showed that the two adsorbents adsorb phenol from hexane solution through hydrogen-bonding and π-π stacking interaction. 展开更多
关键词 poly(methyl p-vinylbenzyl ether) poly(phenyl p-vinylbenzyl ether) adsorption HYDROGEN-BONDING π-π stacking interaction.
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Distribution of polybrominated diphenyl ethers and decabromodiphenylethane in surface sediments from Fuhe River and Baiyangdian Lake,North China 被引量:21
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作者 Guocheng Hu Zhencheng Xu +5 位作者 Jiayin Dai Bixian Mai Hong Cao Jianshe Wang Zhimin Shi Muqi Xu 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2010年第12期1833-1839,共7页
Nineteen surface sediment samples collected from Baiyangdian Lake and its inflowing river (Fuhe River) in North China were analyzed for polybrominated diphenyl ethers (PBDEs) and decabromodiphenylethane (DBDPE).... Nineteen surface sediment samples collected from Baiyangdian Lake and its inflowing river (Fuhe River) in North China were analyzed for polybrominated diphenyl ethers (PBDEs) and decabromodiphenylethane (DBDPE). The concentrations of PBDEs and DBDPE in sediments ranged from 5.5 to 300.7 ng/g dry weight (dw) and 1.1 to 68.2 ng/g dw, respectively. Their levels in sediments in Fuhe River were significantly higher than those in Balyandian Lake. Compared to data from other regions, the PBDE levels in surface sediments from Baiyangdian Lake and Fuhe River were in the medium to lower range. Among the PBDE congeners, BDE209 was predominant, with contributions to the total PBDEs ranging from 79.4% to 97.3% in sediment samples. For the lowly brominated congeners (tri- to hepta-BDE), BDE47 and BDE99 were the most abundant, which contributed 52.1% and 44.1% to the sum of tri- to hepta-BDEs in the sediments from Baiyangdian Lake and Fuhe River, respectively. The compositional patterns of PBDEs in Baiyangdian Lake sediments indicated that technical deca-BDE mixture was the major pollutant sources with a minor contribution of penta-BDE mixture. The present study suggested that the importance of Fuhe River as a possibly potential sources of PBDEs contamination in Baiyangdian Lake. 展开更多
关键词 polybrominated diphenyl ethers decabromodiphenylethane CONTAMINATION profile Baiyangdian Lake Fuhe River
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Polybrominated diphenyl ethers in atmosphere and soil of a production area in China:Levels and partitioning 被引量:14
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作者 Jun Jin Ying Wang +3 位作者 Weizhi Liu Congqiao Yang Jicheng Hu Jian Cui 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2011年第3期427-433,共7页
Polybrominated diphenyl ethers (PBDEs) were measured in atmosphere and soil samples taken in winter and summer at a PBDE production area of Laizhou Bay in China. The concentrations of ∑11PBDE were 0.017-1.17 ng/m3 ... Polybrominated diphenyl ethers (PBDEs) were measured in atmosphere and soil samples taken in winter and summer at a PBDE production area of Laizhou Bay in China. The concentrations of ∑11PBDE were 0.017-1.17 ng/m3 in gaseous phase, 0.5-161.1 ng/m3 in particulate phase, and 73-2629 ng/g dry weight in soil samples. The PBDE congener pattern in the gaseous phase differed from that in the particulate phase, and the PBDE congener pattern in the particulate phase was similar with that in soil. This demonstrated that there was little difference with atmospheric particle-soil transfer efficiency among PBDE congeners. In addition, there were seasonal variations in percentages on particle for lower brominated congeners. The BDE-28 was mostly in the gaseous phase in summer (88.3%), whereas the average proportion of BDE-28 in gaseous phase in winter was 38.9%. Higher brominated congeners (i.e., BDE-206, BDE- 207, BDE-208, and BDE-209) were bound to the atmospheric particulate phase, and their potentials for long-range migration were mainly affected by the environmental behavior of atmospheric particles. Results indicated that PBDE congeners in summer were closer to gas-particle partition equilibrium than in winter. Temperature should be considered the main factor causing nonequilibrium in winter. 展开更多
关键词 polybrominated diphenyl ethers ATMOSPHERE SOIL partitioning production area
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A review of polybrominated diphenyl ethers and alternative brominated flame retardants in wildlife from China:Levels,trends,and bioaccumulation characteristics 被引量:19
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作者 Jiangping Wu Ying Zhang +4 位作者 Xiaojun Luo Yazhe She Lehuan Yu Shejun Chen Bixian Mai 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2012年第2期183-194,共12页
Accelerated industrialization and urbanization,and unregulated disposal of waste of electric and electronic equipment(e-waste) in China have caused environmental pollution of brominated flame retardants(BFRs).This... Accelerated industrialization and urbanization,and unregulated disposal of waste of electric and electronic equipment(e-waste) in China have caused environmental pollution of brominated flame retardants(BFRs).This review summarized the levels,trends,and bioaccumulation characteristics of polybrominated diphenyl ethers(PBDEs) and other potential alternative BFRs including hexabromocyclododecanes(HBCDs),1,2-bis(2,4,6-dibromophenoxy) ethane(BTBPE) and decabromodiphenylethane(DBDPE) in wildlife from China.PBDE levels in wildlife from China were generally higher than those from other parts in Asia,and were comparable to those from Europe but were lower than those from North America.However,wildlife from the e-waste recycling sites in South China and East China contained much higher PBDEs compared to other reports around the world,suggesting the heavy contamination of PBDEs in these regions.The alternative BFRs were also detected in wildlife,revealing that the animals are exposed to these chemicals,in addition to PBDEs.Temporal trends indicated by levels in marine mammals from South China suggested that PBDE levels increased from the beginning of 1990s to 2000s,but decreased from the middle of 2000s,followed by relatively steady levels.In contrast,HBCDs were found to be continuously increasing from 1997 to 2007,indicating the increasing usage of HBCDs in China in recent years.Compared to PBDE profiles found in other parts,aquatic species and birds from China contained relatively higher contributions of BDE28 and 209,respectively,suggesting the possible different usage pattern of PBDEs.Future works including keeping monitoring at a reasonable scale and frequency to make sure levels near urban centers indicative of population do not increase are needed.Additionally,focus effort on e-waste recycling regions to look for impacts and to determine if regulation/controls are resulting in lower environmental contamination,and incorporation of sentinel species in monitoring efforts are recommended. 展开更多
关键词 brominated flame retardants polybrominated diphenyl ethers WILDLIFE electronic waste China
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Semi-interpenetrating polymer networks toward sulfonated poly(ether ether ketone) membranes for high concentration direct methanol fuel cell 被引量:1
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作者 Xupo Liu Yunfeng Zhang +6 位作者 Shaofeng Deng Cuicui Li Jiaming Dong Jiaying Wang Zehui Yang Deli Wang Hansong Cheng 《Chinese Chemical Letters》 SCIE CAS CSCD 2019年第2期299-304,共6页
Low methanol permeability of proton exchange membranes (PEMs) is greatly important for direct methanol fuel cells (DMFCs). Here, sulfonated poly (ether ether ketone) (SPEEK) based semiinterpenetrating polymer networks... Low methanol permeability of proton exchange membranes (PEMs) is greatly important for direct methanol fuel cells (DMFCs). Here, sulfonated poly (ether ether ketone) (SPEEK) based semiinterpenetrating polymer networks (semi-IPNs) are successfully prepared by interpenetrating SPEEK into the in-situ synthesized crosslinking networks. The polymeric networks are formed by the covalent bonds between bromobenzyl groups of bro mo methylated poly (phenylene oxide) and amine groups of diamine linkers as well as the ionic bonds between amine species and sulfonated groups. Two linkers without and with sulfonated groups are applied to fabricate the semi-IPNs. The core properties of the membranes, like phase separation, water uptake, proton conductivity and methanol permeability, are systematically studied and compared. The DMFCs assembled by using the semi-IPN membranes display better performance than Nafion 117 in high concentration methanol solutions. The present work provides a facile way to prepare PEMs with enhanced DMFC performance. 展开更多
关键词 Direct METHANOL fuel cell Proton exchange membrane Semi-interpenetrating polymer networks SULFONATED poly(ether ether ketone) Bromomethylated poly(phenylene oxide)
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Chloromethylation and Quaternization of Poly(aryl ether ketone sulfone)s with Clustered Electron-rich Phenyl Groups for Anion Exchange Membranes 被引量:4
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作者 Lei Xiong Yuan-Fang Hu +2 位作者 Zi-Gui Zheng Zai-Lai Xie Dong-Yang Chen 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2020年第3期278-287,I0007,共11页
Ion segregation is critically important for achieving high ion conductivity for anion exchange membranes(AEMs).Herein,a new bisphenol monomer bearing ten electron-rich phenyl groups was designed and polymerized with v... Ion segregation is critically important for achieving high ion conductivity for anion exchange membranes(AEMs).Herein,a new bisphenol monomer bearing ten electron-rich phenyl groups was designed and polymerized with various amounts of electron-deficient 4,4′-dihydroxydiphenylsulfone and 4,4′-difluorobenzophenone to yield dense and selective reaction sites for chloromethylation and quaternization.As the most challenging step,chloromethylation was optimized by tuning the reaction temperature,reaction time,and reactant ratios.Ion exchange capacity,water uptake,anion conductivity,mechanical stability,and alkaline stability of the resulting AEMs were characterized in detail.It is found that chloromethylation reaction needed to be carried out at low equivalent of chloromethylation agents to avoid undesirable crosslinking.The QA-PAEKS-20 sample with an IEC of 1.19 mmol·g^-1 exhibited a Cl^–conductivity of 11.2 mS·cm^-1 and a water uptake of 30.2%at80°C,which are promising for AEM applications. 展开更多
关键词 Anion exchange membrane CHLOROMETHYLATION poly(aryl ether) Ion-segregation Anion conductivity
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Synthesis of Novel Poly(aryl ether amide)s Containing the Phthalazinone Moiety 被引量:4
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作者 Lin CHENG~1 Xi Gao JIAN~2 (~1Department of Materials Science & Engineering, Wuhan Institute of Chemical Technology. Wuhan 430074) (Department of Polymer Science & Materials. DaLian University of Technology. DaLian 1 16012) 《Chinese Chemical Letters》 SCIE CAS CSCD 2000年第4期307-310,共4页
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
关键词 poly(aryl ether amide)s PHTHALAZINONE direct polymerization heterocyclic diamine
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SYNTHESIS AND CHARACTERIZATION OF BLUE LIGHT-EMITTING POLY(ARYL ETHER)S CONTAINING PYRIMIDINE-INCORPORATED OLIGOFLUORENE PENDANTS WITH BIPOLAR FEATURE 被引量:3
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作者 Guo-xin Jiang Chun-lei Bian +1 位作者 丁军侨 王利祥 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2013年第5期787-797,共11页
Novel blue light-emitting poly(aryl ether)s comprising of bipolar oligofluorene pendants as chromophores have been designed and synthesized, in which pyrimidine and arylamine moieties are utilized as the electron ac... Novel blue light-emitting poly(aryl ether)s comprising of bipolar oligofluorene pendants as chromophores have been designed and synthesized, in which pyrimidine and arylamine moieties are utilized as the electron acceptor and electron donor, respectively. Through varying n bridge length from monofluorene to bifluorene and end-cappers from hydrogen to carbazole and diphenylamine, the emission color of the resulting polymers covers from deep blue to greenish blue, and their HOMO and LUMO levels can be modulated to facilitate charge injection to improve the device performance. Polymer light- emitting diodes (PLEDs) are fabricated with the device structure of ITO/poly(3,4-ethylenedioxythiophene):poly(styrene sulfonic acid) (PEDOT:PSS) (50 nm)/polymer (80 nm)/Ca (10 nm)/Al (200 nm). Among these polymers, P2Cz5F-Py with bifluorene bridge and carbazole end-capper shows excellent trade-off between the efficiency and emission wavelength, having a peak luminous efficiency as high as 1.26 cd/A and Commission Internationale de L'Eclairage (CIE) coordinates of (0.17,0.17). 展开更多
关键词 poly(aryl ether)s PYRIMIDINE Oligofluorene BIPOLAR PLEDs.
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Mechanism of chain propagation for the synthesis of polyoxymethylene dimethyl ethers 被引量:36
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作者 Yupei Zhao Zheng Xu +2 位作者 Hui Chen Yuchuan Fu Jianyi Shen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2013年第6期833-836,共4页
Polyoxymethylene dimethyl ethers(PODE)were synthesized from the reaction of paraformaldehyde with dimethoxymethane(DMM)over different acid catalysts at different conditions.Products were found to follow the Schulz-Flo... Polyoxymethylene dimethyl ethers(PODE)were synthesized from the reaction of paraformaldehyde with dimethoxymethane(DMM)over different acid catalysts at different conditions.Products were found to follow the Schulz-Flory distribution law.The chain propagation proceeds through the insertion of an individual segment of CH2O one by one,while the simultaneous insertion of a few CH2O segments or their assembly is unlikely.Due to the restriction of this law,it is difficult to increase the selectivity to the desired products(e.g.,PODE3 4). 展开更多
关键词 polyoxymethylene dimethyl ethers (PODE) diesel additive chain propagation product distribution Schulz-Flory law
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Tetra-alkylsulfonate functionalized poly(aryl ether) membranes with nanosized hydrophilic channels for efficient proton conduction 被引量:4
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作者 Lijun Zhou Junyang Zhu +3 位作者 Meijin Lin Jiaqi Xu Zailai Xie Dongyang Chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2020年第1期57-64,I0003,共9页
The microstructure of polymer electrolyte membranes plays a key role in ion conductivity and water transport.Herein,fluorinated poly(aryl ether)s with tetra-alkylsulfonate side chains(SFPAEs)have been successfully syn... The microstructure of polymer electrolyte membranes plays a key role in ion conductivity and water transport.Herein,fluorinated poly(aryl ether)s with tetra-alkylsulfonate side chains(SFPAEs)have been successfully synthesized from the copolymerization of a newly developed tetra-allyl-containing bisphenol(TABP)monomer,followed by the thiol-ene addition with sodium 3-mercapto-1-propanesulfonate to attach the ionic groups at the end of the flexible chains.Being the first of its kind,the densely distributed and lengthy alkylsulfonate group possesses the benefit of ease to self-assemble into hydrophilic domains during membrane preparation via solution casting.Indeed,the TEM characterizations revealed that distinct hydrophilic channels of 1-2 nm width had been formed,much larger than those of a home-made control sample where only di-alkylsulfonate side chains were attached.The SFPAE-4-45 with an IECw of 2.0 mmol g^-1 exhibited an enhanced proton conductivity of 143.7 m S cm^-1 at room temperature,which was superior to that of Nafion 212(91.0 m S cm^-1).Furthermore,the oxidative stabilities of SFPAEs were significantly higher than those of non-fluorinated analogs in literature.This study offered a new route to engineering the pendent structure of ionomers for well-defined microscopic morphologies. 展开更多
关键词 Proton exchange membrane poly(arylene ether) Nano-phase separation Thiol-ene addition
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Synthesis and characterization of novel poly(aryl ether sulfone ketone)s containing phthalazinone and biphenyl moieties 被引量:3
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作者 Li Hong Xiao Cheng Liu Xi Gao Jian 《Chinese Chemical Letters》 SCIE CAS CSCD 2008年第2期227-229,共3页
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
关键词 poly(aryl ether sulfone ketone) PHTHALAZINONE BIPHENYL Thermal property Solubility
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Chemical equilibrium controlled synthesis of polyoxymethylene dimethyl ethers over sulfated titania 被引量:18
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作者 Huaju Li Huanling Song +2 位作者 Feng Zhao Liwei Chen Chungu Xia 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2015年第2期239-244,共6页
The chemical equilibrium and reaction kinetic behavior in the synthesis of polyoxymethylene dimethyl ethers (DMMn) were investigated over sulfated titania in order to reveal the decisive factor controlling the react... The chemical equilibrium and reaction kinetic behavior in the synthesis of polyoxymethylene dimethyl ethers (DMMn) were investigated over sulfated titania in order to reveal the decisive factor controlling the reaction. The results showed that the molar ratio of adjacent DMMn products in equilibrium solution had the same value, which depended absolutely on the reaction temperature. Meanwhile, the reactions had the same DMMn products distributions under varied reaction conditions. The equilibrium constants of the related step-wise reactions for DMMn formation were equal, which were calculated based on the bulk compositions of the reaction solution. And thus, the selectivity to DMMn was mainly controlled by the chemical equilibrium, i.e., thermodynamic control. In brief, the present results provide some guidance for future synthesis of DMMn. 展开更多
关键词 polyoxymethylene dimethyl ethers sulfated titania chemical equilibrium reaction kinetic molar ratio
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Immobilization of Bovine Serum Albumin on Poly(ether ether ketone) for Surface Biocompatibility Improvement 被引量:4
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作者 SUN Hui CHEN Rui-chao +1 位作者 LI Ang XU Guo-zhi 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2012年第2期353-357,共5页
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
关键词 polyether ether ketone)(PEEK) UV-grafting Bovine serum albumin immobilization
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Synthesis of Poly(phthalazinone ether ketone) Containing Sodium Sulfonate Groups via Direct Polymerization 被引量:3
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作者 Shou Hai ZHANG Xi Gao JIAN +1 位作者 Guo Qing WANG Wen Xia LI 《Chinese Chemical Letters》 SCIE CAS CSCD 2002年第10期926-928,共3页
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
关键词 SULFONATION SYNTHESIS poly(phthalazinone ether ketone).
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Proton-Exchange Sulfonated Poly (ether ether ketone) (SPEEK)/SiOx-S Composite Membranes in Direct Methanol Fuel Cells 被引量:6
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作者 高启君 王宇新 +2 位作者 许莉 卫国强 王志涛 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2009年第2期207-213,共7页
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
关键词 sulfonated polyether ether ketone) functionalized silica composite membrane direct methanol fuel cell
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