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
Cationic ring-opening polymerization of 3,3-bis(chloromethyl)oxacyclobutane catalyzed by BF3.OEt2 was carded out in ionic liquids [bmim]BF4 and [bmim]PF6. The influences of BCMO concentration and molar ratio of BCMO...Cationic ring-opening polymerization of 3,3-bis(chloromethyl)oxacyclobutane catalyzed by BF3.OEt2 was carded out in ionic liquids [bmim]BF4 and [bmim]PF6. The influences of BCMO concentration and molar ratio of BCMO/BF3.OEt2 on the molecular weights and yield of PBCMO were investigated. The polymerization in ionic liquids proceed to high conversions, although molecular weights are limited, similar to polymerization in organic solvent such as CH2Cl2. Follow a viewpoint of green chemistry, we feel ionic liquid [bmim]BF4 is superior to [bmim]PF6. Extracting [bmim]PF6 from the product using organic solvent as extractant limits its advantage as a green reaction media.展开更多
The goal of this paper was to reveal the feasibility of chloromethylation of polymers made from technical divinylbenzene so as to introduce functional groups into polymeric adsorbents. For this study, the factors that...The goal of this paper was to reveal the feasibility of chloromethylation of polymers made from technical divinylbenzene so as to introduce functional groups into polymeric adsorbents. For this study, the factors that effect the chloromethylation reaction, such as the pore structure of the polymer, the ratio of the reactants to catalyst, the reaction temperature and reaction time and so on were investigated, and the pore structure and property of the chloromethylated polymers were studied. The results showed that polymers of technical divinylbenzene could be chloromethylated successfully, and the adsorptive property of the chloromethylated resin was different from that of the initial resin.展开更多
The chloromethylation reaction of substituted titanocenes (η~5-C_5H_5)(η~5-C_5H_4CRR'C_6H_4X)TiCl2 1 in the presence of polyformaldehyde and dry hydrogen chloride isreported.
The Ziegler-Natta type catalytic systems composed of lanthanide compound and ethyl aluminum sesquichloride are effective to convert chloromethyl thiirane to polymer of molecular weight ca. 10,000. The effects of rare ...The Ziegler-Natta type catalytic systems composed of lanthanide compound and ethyl aluminum sesquichloride are effective to convert chloromethyl thiirane to polymer of molecular weight ca. 10,000. The effects of rare earth element and ligand were studied.展开更多
Ring opening polymerization of (chloromethyl) thiirane (CMT) usingrare earth coordination catalysts has been investigated for the first time: Ithas been found that binary rare earth coordination catalyst composed of r...Ring opening polymerization of (chloromethyl) thiirane (CMT) usingrare earth coordination catalysts has been investigated for the first time: Ithas been found that binary rare earth coordination catalyst composed of rareof phosphonate and trialkyl aluminum are effective catalysts for the polymerization of (chloromethyl)thiirane with high yield. Kinetic studies showed that the polymerization rate is of first order with respect to both monomer concentration and catalyst concentration. The antivation energy of the polyimerization reaction is 28.4kJ/mol.展开更多
2-(Chloromethyl)furan as an electrophile attacks lithium trialkylalkynylborates,followed by the oxidation with H_2O_2 under basic conditions to afford 2-furfurylketones in good yields.
A number of chlorumethylated polystyrenes were synthesized and tried to immobilize aminoacylase from Aspergillus oryzae and many factors which affected immobilized enzyme activity were studied in detail. The results i...A number of chlorumethylated polystyrenes were synthesized and tried to immobilize aminoacylase from Aspergillus oryzae and many factors which affected immobilized enzyme activity were studied in detail. The results indicated that the immobilized enzyme on support(IAR-1) possessed high enzymatic activity and high stability.展开更多
A novel electrolyte with chloromethyl pivalate (CP) used as solvent was first reported for non-aqueous lithium-oxygen (Li-O2) batteries. Since there are no α-H atoms in the structure of CP, the CP based electroly...A novel electrolyte with chloromethyl pivalate (CP) used as solvent was first reported for non-aqueous lithium-oxygen (Li-O2) batteries. Since there are no α-H atoms in the structure of CP, the CP based electrolyte in both superoxide radical solution and real LifO2 battery environment showed good chemical stability against superoxide radicals, which was confirmed by ^1H NMR and ^13C NMR measurements. Without a catalyst in the cathode of Li-O2 batteries, the batteries showed high specific capacity and cycling stability.展开更多
The morphological change of St/DVB crosslinked gels during chloromethylation wasstudied by fluorescence spectroscopy using St/DVB crosslinked and hypercrosslinked gels as controlsamples. It has been found that with in...The morphological change of St/DVB crosslinked gels during chloromethylation wasstudied by fluorescence spectroscopy using St/DVB crosslinked and hypercrosslinked gels as controlsamples. It has been found that with increase of chlorine content, the excimer emission band (~325nm)approaches to vanish, while the intensity of multi-ring aggregate emission band (~420nm) quicklyreaches a maximum, and then decreases sharply accompanied by appearance ofa new broad bandcentred at ca 488nm which roughly coincides with the typical emission band of hypercrossllinkedSt/DVB gels. Mearwhile, the result of IR measurement suggests that methylene bridge between phenylrings forms and increases with chloromethylation process. These results are explained in terms ofaside reaction of post-crosslinking, which densifies the loosely crosslinked networks and undoes thedensely entangled microgel nuclei. As a result, the morphology of the crosslinked gels becom es morehomogeneous with chloromethylation.展开更多
The chloromethylation reaction of 2-chloroethylbenzene was performed successfully by micellar ca-talysis in the biphasic oil/water system. The effects of anionic, cationic and non-ionic surfactants on the reaction wer...The chloromethylation reaction of 2-chloroethylbenzene was performed successfully by micellar ca-talysis in the biphasic oil/water system. The effects of anionic, cationic and non-ionic surfactants on the reaction were compared. The mechanism of chloromethylation reaction and the mechanism of micellar catalysis were investigated. The results show that the micellar catalysis is an effective way to realize the chloromethylation of 2-chloroethylbenzene, and the cationic surfactant shows the most effectiveness. The longer the hydrophobic chain of the cationic surfactant is, the better the catalysis effect will be, and the addition of inorganic electrolyte into the aqueous phase can markedly promote the catalysis effect.展开更多
Chloromethylated mesoporous silica nanoparticles (CM MSN) were synthesized through co-condensation of tetraethoxysilane and (chloro) phenyltrimethoxysilane precursors using hexadecyl trimethyl ammonium bromide as ...Chloromethylated mesoporous silica nanoparticles (CM MSN) were synthesized through co-condensation of tetraethoxysilane and (chloro) phenyltrimethoxysilane precursors using hexadecyl trimethyl ammonium bromide as template.With the addition of the particles into chloromethylated poly (ether ether ketone) (PEEK),the hybrid membranes were prepared by a solution-casting method after complete quatemization of the casting solution.The successful synthesis of the particles was verified by transmission electron microscopy,X-ray diffraction and Fourier transform infrared spectroscopy while the effect of CM MSN incorporation on membrane performance including thermal stability,mechanical strength and hydroxide conductivity was investigated by thermal gravimetric analysis,electronic stretching machine,alternating-current impedance and so on.Owing to the large pore volume and high surface area of the particles,the hybrid membranes exhibited enhanced hydroxide conductivity (88.7% increase at 60 ℃,100% RH with 5.0 wt% filling content) due to an increase in ion concentration and optimization of the channel morphology.Besides,higher mechanical strength,thermal and dimensional stability of hybrid membranes were obtained compared with those of the imidazolium PEEK membrane.展开更多
The structures and stabilities of these still experimentally unknown CHnCl3-nO2-Li^+ and CFnCl3-nO2-Li^+ ions have been theoretically investigated by ab initio molecular orbital theory and density functional theory ...The structures and stabilities of these still experimentally unknown CHnCl3-nO2-Li^+ and CFnCl3-nO2-Li^+ ions have been theoretically investigated by ab initio molecular orbital theory and density functional theory (DFT) in conjunction with the 6-311G(d,p), 6-311 +G(d,p), 6-311 +G(2d,p) and 6-311 +G(2df,2p) basis sets. The optimized geometries, chemical bonding and NBO analysis indicate that these complexes of CHnCl3-nO2-Li^+ and CFnCl3-nO2- Li^+ exist as ion-dipole molecules. The calculated affinity energies of these species exceed 41.9 kJ/mol, which are large enough to suggest the possibility that these title complexes could be detected as stable species in gas phase by Li^+ ion attachment mass spectrometry.展开更多
通过对羧基丁腈胶乳微生物污染情况及防腐剂残留量的测试,发现在高温海运条件下,原用于胶乳中的防腐剂卡松(通常其活性成分氯甲基异噻唑啉酮与甲基异噻唑啉酮的质量比为3/1)容易失效,导致胶乳腐败变质。防腐剂活性物在50℃下的热储实验...通过对羧基丁腈胶乳微生物污染情况及防腐剂残留量的测试,发现在高温海运条件下,原用于胶乳中的防腐剂卡松(通常其活性成分氯甲基异噻唑啉酮与甲基异噻唑啉酮的质量比为3/1)容易失效,导致胶乳腐败变质。防腐剂活性物在50℃下的热储实验表明,甲基异噻唑啉酮在经历了初期的迅速降解后,在热储中保持稳定,降解率均值54.5%;氯甲基异噻唑啉酮在热储14 d内几乎完全降解。进而考察了含有甲基异噻唑啉酮的防腐剂Acticide M 10和Acticide M 10 S对羧基丁腈胶乳的防腐效果,结果显示,添加浓度为450×10^(-6)的防腐剂Actidice M 10的羧基丁腈胶乳,经过高温海运后仍有良好的防腐效果。展开更多
基金financially supported by the National Natural Science Foundation of China (Nos. 51873037 and 51503038)
文摘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.
基金financially supported by the Key Project of Chinese Ministry of Education(No.105075)the National Natural Science Foundation of China(No.20503016).
文摘Cationic ring-opening polymerization of 3,3-bis(chloromethyl)oxacyclobutane catalyzed by BF3.OEt2 was carded out in ionic liquids [bmim]BF4 and [bmim]PF6. The influences of BCMO concentration and molar ratio of BCMO/BF3.OEt2 on the molecular weights and yield of PBCMO were investigated. The polymerization in ionic liquids proceed to high conversions, although molecular weights are limited, similar to polymerization in organic solvent such as CH2Cl2. Follow a viewpoint of green chemistry, we feel ionic liquid [bmim]BF4 is superior to [bmim]PF6. Extracting [bmim]PF6 from the product using organic solvent as extractant limits its advantage as a green reaction media.
文摘The goal of this paper was to reveal the feasibility of chloromethylation of polymers made from technical divinylbenzene so as to introduce functional groups into polymeric adsorbents. For this study, the factors that effect the chloromethylation reaction, such as the pore structure of the polymer, the ratio of the reactants to catalyst, the reaction temperature and reaction time and so on were investigated, and the pore structure and property of the chloromethylated polymers were studied. The results showed that polymers of technical divinylbenzene could be chloromethylated successfully, and the adsorptive property of the chloromethylated resin was different from that of the initial resin.
文摘The chloromethylation reaction of substituted titanocenes (η~5-C_5H_5)(η~5-C_5H_4CRR'C_6H_4X)TiCl2 1 in the presence of polyformaldehyde and dry hydrogen chloride isreported.
文摘The Ziegler-Natta type catalytic systems composed of lanthanide compound and ethyl aluminum sesquichloride are effective to convert chloromethyl thiirane to polymer of molecular weight ca. 10,000. The effects of rare earth element and ligand were studied.
文摘Ring opening polymerization of (chloromethyl) thiirane (CMT) usingrare earth coordination catalysts has been investigated for the first time: Ithas been found that binary rare earth coordination catalyst composed of rareof phosphonate and trialkyl aluminum are effective catalysts for the polymerization of (chloromethyl)thiirane with high yield. Kinetic studies showed that the polymerization rate is of first order with respect to both monomer concentration and catalyst concentration. The antivation energy of the polyimerization reaction is 28.4kJ/mol.
基金Project Supported by the National Natural Science Foundation of China
文摘2-(Chloromethyl)furan as an electrophile attacks lithium trialkylalkynylborates,followed by the oxidation with H_2O_2 under basic conditions to afford 2-furfurylketones in good yields.
文摘A number of chlorumethylated polystyrenes were synthesized and tried to immobilize aminoacylase from Aspergillus oryzae and many factors which affected immobilized enzyme activity were studied in detail. The results indicated that the immobilized enzyme on support(IAR-1) possessed high enzymatic activity and high stability.
基金supported by the National Basic Research Program of China (No. 2014CB932303)National Natural ScienceFoundation of China (No. 21573145)
文摘A novel electrolyte with chloromethyl pivalate (CP) used as solvent was first reported for non-aqueous lithium-oxygen (Li-O2) batteries. Since there are no α-H atoms in the structure of CP, the CP based electrolyte in both superoxide radical solution and real LifO2 battery environment showed good chemical stability against superoxide radicals, which was confirmed by ^1H NMR and ^13C NMR measurements. Without a catalyst in the cathode of Li-O2 batteries, the batteries showed high specific capacity and cycling stability.
基金National Natural Scientific Foundation of China (Project grant No.29574165 29928003+1 种基金 29874019) National Natural Scientific Foundation of Tianjin (Project grant No.013604011)
文摘The morphological change of St/DVB crosslinked gels during chloromethylation wasstudied by fluorescence spectroscopy using St/DVB crosslinked and hypercrosslinked gels as controlsamples. It has been found that with increase of chlorine content, the excimer emission band (~325nm)approaches to vanish, while the intensity of multi-ring aggregate emission band (~420nm) quicklyreaches a maximum, and then decreases sharply accompanied by appearance ofa new broad bandcentred at ca 488nm which roughly coincides with the typical emission band of hypercrossllinkedSt/DVB gels. Mearwhile, the result of IR measurement suggests that methylene bridge between phenylrings forms and increases with chloromethylation process. These results are explained in terms ofaside reaction of post-crosslinking, which densifies the loosely crosslinked networks and undoes thedensely entangled microgel nuclei. As a result, the morphology of the crosslinked gels becom es morehomogeneous with chloromethylation.
文摘The chloromethylation reaction of 2-chloroethylbenzene was performed successfully by micellar ca-talysis in the biphasic oil/water system. The effects of anionic, cationic and non-ionic surfactants on the reaction were compared. The mechanism of chloromethylation reaction and the mechanism of micellar catalysis were investigated. The results show that the micellar catalysis is an effective way to realize the chloromethylation of 2-chloroethylbenzene, and the cationic surfactant shows the most effectiveness. The longer the hydrophobic chain of the cationic surfactant is, the better the catalysis effect will be, and the addition of inorganic electrolyte into the aqueous phase can markedly promote the catalysis effect.
文摘Chloromethylated mesoporous silica nanoparticles (CM MSN) were synthesized through co-condensation of tetraethoxysilane and (chloro) phenyltrimethoxysilane precursors using hexadecyl trimethyl ammonium bromide as template.With the addition of the particles into chloromethylated poly (ether ether ketone) (PEEK),the hybrid membranes were prepared by a solution-casting method after complete quatemization of the casting solution.The successful synthesis of the particles was verified by transmission electron microscopy,X-ray diffraction and Fourier transform infrared spectroscopy while the effect of CM MSN incorporation on membrane performance including thermal stability,mechanical strength and hydroxide conductivity was investigated by thermal gravimetric analysis,electronic stretching machine,alternating-current impedance and so on.Owing to the large pore volume and high surface area of the particles,the hybrid membranes exhibited enhanced hydroxide conductivity (88.7% increase at 60 ℃,100% RH with 5.0 wt% filling content) due to an increase in ion concentration and optimization of the channel morphology.Besides,higher mechanical strength,thermal and dimensional stability of hybrid membranes were obtained compared with those of the imidazolium PEEK membrane.
基金Project supported by the National Natural Science Foundation of China and the Center for Computational Science, Hefei Institutes of Physical Science (No. 0330405002).
文摘The structures and stabilities of these still experimentally unknown CHnCl3-nO2-Li^+ and CFnCl3-nO2-Li^+ ions have been theoretically investigated by ab initio molecular orbital theory and density functional theory (DFT) in conjunction with the 6-311G(d,p), 6-311 +G(d,p), 6-311 +G(2d,p) and 6-311 +G(2df,2p) basis sets. The optimized geometries, chemical bonding and NBO analysis indicate that these complexes of CHnCl3-nO2-Li^+ and CFnCl3-nO2- Li^+ exist as ion-dipole molecules. The calculated affinity energies of these species exceed 41.9 kJ/mol, which are large enough to suggest the possibility that these title complexes could be detected as stable species in gas phase by Li^+ ion attachment mass spectrometry.
文摘通过对羧基丁腈胶乳微生物污染情况及防腐剂残留量的测试,发现在高温海运条件下,原用于胶乳中的防腐剂卡松(通常其活性成分氯甲基异噻唑啉酮与甲基异噻唑啉酮的质量比为3/1)容易失效,导致胶乳腐败变质。防腐剂活性物在50℃下的热储实验表明,甲基异噻唑啉酮在经历了初期的迅速降解后,在热储中保持稳定,降解率均值54.5%;氯甲基异噻唑啉酮在热储14 d内几乎完全降解。进而考察了含有甲基异噻唑啉酮的防腐剂Acticide M 10和Acticide M 10 S对羧基丁腈胶乳的防腐效果,结果显示,添加浓度为450×10^(-6)的防腐剂Actidice M 10的羧基丁腈胶乳,经过高温海运后仍有良好的防腐效果。