Login In
2013 Volume 30 Issue 8
2013, 30(8): 855-860
doi: 10.3724/SP.J.1095.2013.20587
Abstract:
Cerium-Zinc redox flow battery has a significant high voltage compared with other redox flow batteries. The potential utilization of cerium-zinc redox flow battery is most likely to occur in energy storage system due to the abundant resources of raw materials and cost-efficient products. This review summarized the recent research and development of cerium-zinc flow batteries,especially for electrolytes of batteries,and analyzes further development prospective of cerium-zinc flow batteries.
Cerium-Zinc redox flow battery has a significant high voltage compared with other redox flow batteries. The potential utilization of cerium-zinc redox flow battery is most likely to occur in energy storage system due to the abundant resources of raw materials and cost-efficient products. This review summarized the recent research and development of cerium-zinc flow batteries,especially for electrolytes of batteries,and analyzes further development prospective of cerium-zinc flow batteries.
2013, 30(8): 861-866
doi: 10.3724/SP.J.1095.2013.20446
Abstract:
Sixteen lateral multi-fluorine substituted internal alkynes liquid crystals were synthesized via a series of reactions including substituted phenylboronic acidation,Suzuki cross-coupling,Sonogashira crosscoupling and iodination using 4-bromo-alkylbenzene and 4-bromo-2,3-difluoro-phenol precursors. The structures of the products were characterized by means of IR,NMR and MS. The differential scanning calorimetric,polarizing microscope and Abbe refractometer,were used to investigate their properties.The results demonstrate that the compounds possess low melting point,wide phase transition interval and high optical anisotropy value(△n > 0.3). The obtained liquid crystals might find broad potential applications in dual-frequency liquid crystals.
Sixteen lateral multi-fluorine substituted internal alkynes liquid crystals were synthesized via a series of reactions including substituted phenylboronic acidation,Suzuki cross-coupling,Sonogashira crosscoupling and iodination using 4-bromo-alkylbenzene and 4-bromo-2,3-difluoro-phenol precursors. The structures of the products were characterized by means of IR,NMR and MS. The differential scanning calorimetric,polarizing microscope and Abbe refractometer,were used to investigate their properties.The results demonstrate that the compounds possess low melting point,wide phase transition interval and high optical anisotropy value(△n > 0.3). The obtained liquid crystals might find broad potential applications in dual-frequency liquid crystals.
2013, 30(8): 867-871
doi: 10.3724/SP.J.1095.2013.20427
Abstract:
An improved procedure was developed for the synthesis of 1-benzyl-3-alkylbenzotriazolium ionic liquids from commercially available starting materials. The structures of target compounds were characterized by FT-IR,1H NMR and 13C NMR. The yield reaches 82.7%~86.1% when the molar ratio of substituted alkyl benzotriazole to cuprous iodide and benzyl bromide is 10:2.5:11,and the reaction time is 5~6 h. Moreover,their solubility,the relationship between molecular structure and melting point of the ionic liquids were investigated.
An improved procedure was developed for the synthesis of 1-benzyl-3-alkylbenzotriazolium ionic liquids from commercially available starting materials. The structures of target compounds were characterized by FT-IR,1H NMR and 13C NMR. The yield reaches 82.7%~86.1% when the molar ratio of substituted alkyl benzotriazole to cuprous iodide and benzyl bromide is 10:2.5:11,and the reaction time is 5~6 h. Moreover,their solubility,the relationship between molecular structure and melting point of the ionic liquids were investigated.
2013, 30(8): 872-877
doi: 10.3724/SP.J.1095.2013.20458
Abstract:
Two kinds of 2-chloromethyl-benzimidazole were synthesized by substituted o-diaminobenzene and monochloroacetic acid in hydrochloric acid solution. With substituted carboxylic acid as the starting materials,ten kinds of 1,3,4-oxadiazoles were prepared via esterification,hydrazinolysis,followed by reaction with carbon disulfide in potassium hydroxide solution. At last,fourteen new target compounds were synthesized by reacting 5-substituted-1,3,4-oxadiazole-3-thiol with 2-chloromethyl-5-substituted-bezoimidazole in sodium hydroxide solution. The structures of all the compounds were characterized by IR,1H NMR and elemental analysis. Preliminary biological activity experiments showed that the synthesized compounds had certain effects on the wheat gemma and germination of mung bean.
Two kinds of 2-chloromethyl-benzimidazole were synthesized by substituted o-diaminobenzene and monochloroacetic acid in hydrochloric acid solution. With substituted carboxylic acid as the starting materials,ten kinds of 1,3,4-oxadiazoles were prepared via esterification,hydrazinolysis,followed by reaction with carbon disulfide in potassium hydroxide solution. At last,fourteen new target compounds were synthesized by reacting 5-substituted-1,3,4-oxadiazole-3-thiol with 2-chloromethyl-5-substituted-bezoimidazole in sodium hydroxide solution. The structures of all the compounds were characterized by IR,1H NMR and elemental analysis. Preliminary biological activity experiments showed that the synthesized compounds had certain effects on the wheat gemma and germination of mung bean.
2013, 30(8): 878-882
doi: 10.3724/SP.J.1095.2013.20584
Abstract:
Seven carbonyl compounds were thionated with phosphorus pentasulfide promoted by microwave irradiation under solvent-free conditions. The thiocarbonyl compounds were synthesized in 76%~93% yields. The optimized reaction conditions:the molar ratio of substrates and PP2S5 is 4:1,temperature is 100℃ and time is 15~20 min. The structures of products were characterized by 1H NMR and 13C NMR.
Seven carbonyl compounds were thionated with phosphorus pentasulfide promoted by microwave irradiation under solvent-free conditions. The thiocarbonyl compounds were synthesized in 76%~93% yields. The optimized reaction conditions:the molar ratio of substrates and PP2S5 is 4:1,temperature is 100℃ and time is 15~20 min. The structures of products were characterized by 1H NMR and 13C NMR.
2013, 30(8): 883-887
doi: 10.3724/SP.J.1095.2013.20417
Abstract:
The addition reaction of a lactic acid-based diol intermediate(LPEG),hydroxyapatite with toluene 2,4-diisocyanate(TDI) was employed to form the covalent hybrid of hydroxyapatite and lactic acid-based polyurethane. The structure and thermal stability of the hybrid were analyzed and compared with the corresponding blends. Thermogravimetric analysis shows that the remained fractions of HA-g-LPEU5K and HA/LPEU5K are 92.5% and 41.7%,respectively. The hydrids are still homogeneous while precipitation is found in the blend solutions after settling at temperature for three days. The stability of the hybrid is significantly higher than that of the blends,which confirms that the covalent hybrid of lactic acid-based polyurethane and hydroxyapatite is successfully obtained.In addition,the hybrid systems exhibit degradable properties.
The addition reaction of a lactic acid-based diol intermediate(LPEG),hydroxyapatite with toluene 2,4-diisocyanate(TDI) was employed to form the covalent hybrid of hydroxyapatite and lactic acid-based polyurethane. The structure and thermal stability of the hybrid were analyzed and compared with the corresponding blends. Thermogravimetric analysis shows that the remained fractions of HA-g-LPEU5K and HA/LPEU5K are 92.5% and 41.7%,respectively. The hydrids are still homogeneous while precipitation is found in the blend solutions after settling at temperature for three days. The stability of the hybrid is significantly higher than that of the blends,which confirms that the covalent hybrid of lactic acid-based polyurethane and hydroxyapatite is successfully obtained.In addition,the hybrid systems exhibit degradable properties.
2013, 30(8): 888-896
doi: 10.3724/SP.J.1095.2013.20466
Abstract:
4,5-Bis(3',5'-di-tert-butylphenylethynyl)-2-methoxyphenol(dendron) was synthesized from 3,5di-tertbutyl phenol,trifluoromethanesulfonic anhydride and 4,5-diethynyl-2-methoxyphenol. The phenolic hydroxyl group was subsequently esterified by trifluoromethanesulfonic anhydride. By coupling different chromophores(biphenyl,azobenzene,anthracene,pyrene) on the as-obtained sulfonic esters,π-conjugate unsymmetrical dendrimers with different cores were obtained. 1H NMR,13C NMR spectroscopy,FT-IR spectroscopy and element analysis were deployed to characterize the resultant products. The solubility of the dendrimers reveals that,compared to the cores(varieties of chromophores),all dendrimers are soluble in most common organic solvents. Meanwhile,the dendrimers show improved thermostability. These two characters make the dendrimers to be easily blended with other materials or added into equipments.
4,5-Bis(3',5'-di-tert-butylphenylethynyl)-2-methoxyphenol(dendron) was synthesized from 3,5di-tertbutyl phenol,trifluoromethanesulfonic anhydride and 4,5-diethynyl-2-methoxyphenol. The phenolic hydroxyl group was subsequently esterified by trifluoromethanesulfonic anhydride. By coupling different chromophores(biphenyl,azobenzene,anthracene,pyrene) on the as-obtained sulfonic esters,π-conjugate unsymmetrical dendrimers with different cores were obtained. 1H NMR,13C NMR spectroscopy,FT-IR spectroscopy and element analysis were deployed to characterize the resultant products. The solubility of the dendrimers reveals that,compared to the cores(varieties of chromophores),all dendrimers are soluble in most common organic solvents. Meanwhile,the dendrimers show improved thermostability. These two characters make the dendrimers to be easily blended with other materials or added into equipments.
2013, 30(8): 897-902
doi: 10.3724/SP.J.1095.2013.20456
Abstract:
In CH3OH the reaction of CuCl2 with N-(2,4-dichlorophenyl)-N'-(benzoyl)-thiourea gave a new copper(Ⅱ) complex,CuL2(HL=N-benzoyl-N'-(2,4-dichlorophenyl)-O-methyl-isourea),which was derived from the desulfurated hydrogen of N-(2,4-dichlorophenyl)-N'-(benzoyl)-thiourea(H2met). Single crystal was obtained by slowly evaporating solvent at the room temperature,and the molecule structure was determined with X-ray diffractions. The copper(Ⅱ) ion is coordinated by two N atoms and two carbonyl O atoms of two ligand molecules and forms a complex with two six-membered chelate rings[N(1A)-Cu-N(1)=180.0°,O(1A)-Cu(1)-O(1)=180.0°].
In CH3OH the reaction of CuCl2 with N-(2,4-dichlorophenyl)-N'-(benzoyl)-thiourea gave a new copper(Ⅱ) complex,CuL2(HL=N-benzoyl-N'-(2,4-dichlorophenyl)-O-methyl-isourea),which was derived from the desulfurated hydrogen of N-(2,4-dichlorophenyl)-N'-(benzoyl)-thiourea(H2met). Single crystal was obtained by slowly evaporating solvent at the room temperature,and the molecule structure was determined with X-ray diffractions. The copper(Ⅱ) ion is coordinated by two N atoms and two carbonyl O atoms of two ligand molecules and forms a complex with two six-membered chelate rings[N(1A)-Cu-N(1)=180.0°,O(1A)-Cu(1)-O(1)=180.0°].
2013, 30(8): 903-908
doi: 10.3724/SP.J.1095.2013.20439
Abstract:
The effects of hydrophobic group content and micro-block length on viscoelastic properties of P(AM-NaAA-C16DMAAC) (AA:acrylamide, NaAA:sodium acrylate,C16DMAAC:hexadecyl trimethyl allylammonium chloride) solution were studied. The results indicated that the viscoelastic properties could be changed effectively for associative polymers with similar molecular structure and common zero shear viscosity by varying the molecular structures. When increasing the hydrophobic group content,the first normal stress difference (N1) increased and its shearing rate,a speed for N1 to reach the minimum value decreased. Furthermore,when increasing the micro-block length,the viscosities and the viscoelatic rheological properties decreased after initial increasing,so there is an optimum value for the micro-block length.
The effects of hydrophobic group content and micro-block length on viscoelastic properties of P(AM-NaAA-C16DMAAC) (AA:acrylamide, NaAA:sodium acrylate,C16DMAAC:hexadecyl trimethyl allylammonium chloride) solution were studied. The results indicated that the viscoelastic properties could be changed effectively for associative polymers with similar molecular structure and common zero shear viscosity by varying the molecular structures. When increasing the hydrophobic group content,the first normal stress difference (N1) increased and its shearing rate,a speed for N1 to reach the minimum value decreased. Furthermore,when increasing the micro-block length,the viscosities and the viscoelatic rheological properties decreased after initial increasing,so there is an optimum value for the micro-block length.
2013, 30(8): 909-914
doi: 10.3724/SP.J.1095.2013.20475
Abstract:
Series of amphoteric flocculants AAB with outstanding flocculation efficiency and salt tolerance were synthesized by dispersion polymerization using acrylamide(AM) as the main part and positive and negative charge groups as the monomers. The effects of the dispersion medium,stabilizer,monomer and chain transfer agent on the polymerization were investigated by determining the intrinsic viscosity of the copolymer and apparent viscosity. Meanwhile,the flocculation performance and salt resistance of the flocculants were evaluated by flocculation test. Then the optimum reaction conditions were determined as follows:n(AM):n(AA):n(DMBAC)=90:5:5,13%(mass fraction) monomer,0.2% VA -044 as initiator and 6% PDAC as stabilizer(based on the total monomer mass),25% ammonium sulfate(based on the system),500 × 10-6 sodium hypophosphite,1000 × 10-6 sodium formate,polymerization temperature 35℃,polymerization time 24 h. Under the optimum reaction conditions,the amphoteric flocculants had the maximum intrinsic viscosity(for 5.2 dL/g) and better stability. All the results showed that the amphoteric flocculants exhibited excellent flocculation efficiency and salt tolerance due to the lower dosages(for 30 × 10-6) and the higher settlement rates(for 2.56 s-1) in simulated wastewater with high salt concentration.
Series of amphoteric flocculants AAB with outstanding flocculation efficiency and salt tolerance were synthesized by dispersion polymerization using acrylamide(AM) as the main part and positive and negative charge groups as the monomers. The effects of the dispersion medium,stabilizer,monomer and chain transfer agent on the polymerization were investigated by determining the intrinsic viscosity of the copolymer and apparent viscosity. Meanwhile,the flocculation performance and salt resistance of the flocculants were evaluated by flocculation test. Then the optimum reaction conditions were determined as follows:n(AM):n(AA):n(DMBAC)=90:5:5,13%(mass fraction) monomer,0.2% VA -044 as initiator and 6% PDAC as stabilizer(based on the total monomer mass),25% ammonium sulfate(based on the system),500 × 10-6 sodium hypophosphite,1000 × 10-6 sodium formate,polymerization temperature 35℃,polymerization time 24 h. Under the optimum reaction conditions,the amphoteric flocculants had the maximum intrinsic viscosity(for 5.2 dL/g) and better stability. All the results showed that the amphoteric flocculants exhibited excellent flocculation efficiency and salt tolerance due to the lower dosages(for 30 × 10-6) and the higher settlement rates(for 2.56 s-1) in simulated wastewater with high salt concentration.
2013, 30(8): 915-921
doi: 10.3724/SP.J.1095.2013.20473
Abstract:
Preparation of huperzine A molecularly imprinted polymers(MIPs) using silica as sacrificial material was carried out for the first time by using huperzine A as template molecule,methyl acrylic acid as functional monomer,divinyl benzene as cross-linker and 2'-2-azobis-isobutyronitrile as initiator,respectively. The MIPs were characterized by infrared spectroscopy(IR),scanning electron microscopy(SEM) and thermogravimetic analysis. Static method was employed to measure adsorption isotherm and Scatchard analysis was used to investigate on site distribution on the surface of MIPs. Results indicated that such MIPs exhibited a good selective adsorption performance with a selectivity coefficient of 1.399 toward the template. Two types of adsorption sites were mainly found in the matrix of the imprinted polymers with dissociation constants and apparent maximum binding capacity of 0.169 g/L and 0.832 mg/g for the low affinity sites,and 0.776 g/L and 0.213 mg/g for the high affinity ones. Additionally,a good enrichment capability toward huperzine A was also observed when this MIPs was used for solid phase micro-extraction of target compound from crude extract solution of Serrate Clubmoss. A recovery of 93.5% for the product could be achieved.
Preparation of huperzine A molecularly imprinted polymers(MIPs) using silica as sacrificial material was carried out for the first time by using huperzine A as template molecule,methyl acrylic acid as functional monomer,divinyl benzene as cross-linker and 2'-2-azobis-isobutyronitrile as initiator,respectively. The MIPs were characterized by infrared spectroscopy(IR),scanning electron microscopy(SEM) and thermogravimetic analysis. Static method was employed to measure adsorption isotherm and Scatchard analysis was used to investigate on site distribution on the surface of MIPs. Results indicated that such MIPs exhibited a good selective adsorption performance with a selectivity coefficient of 1.399 toward the template. Two types of adsorption sites were mainly found in the matrix of the imprinted polymers with dissociation constants and apparent maximum binding capacity of 0.169 g/L and 0.832 mg/g for the low affinity sites,and 0.776 g/L and 0.213 mg/g for the high affinity ones. Additionally,a good enrichment capability toward huperzine A was also observed when this MIPs was used for solid phase micro-extraction of target compound from crude extract solution of Serrate Clubmoss. A recovery of 93.5% for the product could be achieved.
2013, 30(8): 922-926
doi: 10.3724/SP.J.1095.2013.20485
Abstract:
Inverse suspension combined with the sol-gel method was deployed to prepare a magnetic chitosan microspheres. The lipase was immobilized on magnetic chitosan microspheres with genipin as the cross-linking reagent. The optimum conditions and properties of immobilization enzyme were investigated. The maximal specific activity of 4.31 U/g was achieved when the crosslinking reaction was carried out at 55℃ for 8 h using 0.6 g/L genipin. The optimum pH,temperature and Km of the immobilized enzyme were 8,25~35℃ and 0.26 mol/L,respectively. The immobilized lipase showed improved thermal stability and remained active in a broader pH range,compared with those of free lipase. Such immobilized lipase can be recycled via the magnetic separation for a certain extent.
Inverse suspension combined with the sol-gel method was deployed to prepare a magnetic chitosan microspheres. The lipase was immobilized on magnetic chitosan microspheres with genipin as the cross-linking reagent. The optimum conditions and properties of immobilization enzyme were investigated. The maximal specific activity of 4.31 U/g was achieved when the crosslinking reaction was carried out at 55℃ for 8 h using 0.6 g/L genipin. The optimum pH,temperature and Km of the immobilized enzyme were 8,25~35℃ and 0.26 mol/L,respectively. The immobilized lipase showed improved thermal stability and remained active in a broader pH range,compared with those of free lipase. Such immobilized lipase can be recycled via the magnetic separation for a certain extent.
2013, 30(8): 927-931
doi: 10.3724/SP.J.1095.2013.20435
Abstract:
Fe3O4 magnetic nanoparticles were first prepared using the coprecipitation method and were coated by SiO2. Functional magnetic nanometer materials were then obtained through bonding polyethylenimine(PEI) on the surface of SiO2 and quaternarization with benzyl chloride. Coating of SiO2 could increase the dispersion and stability of Fe3O4 nanometer materials. FT-IR,SEM,TG and vibrating sample magnetometer were used to characterize the magnetic nanomaterials. The results showed that the synthesis of magnetic nanomaterials was successful. The static adsorption method was employed to study the adsorption properties of magnetic nanomaterials towards Cr2O72- and various factors which might influence the adsorption performance of the materials. The optimal conditions for the separation and enrichment environment of heavy chrome acid radical are:acid medium,the temperature is 25℃,potassium dichromate concentration is 0.8 g/L,the adsorption quantity for 120 mg/g,grafting,the greater the amount of adsorption quantity increase.
Fe3O4 magnetic nanoparticles were first prepared using the coprecipitation method and were coated by SiO2. Functional magnetic nanometer materials were then obtained through bonding polyethylenimine(PEI) on the surface of SiO2 and quaternarization with benzyl chloride. Coating of SiO2 could increase the dispersion and stability of Fe3O4 nanometer materials. FT-IR,SEM,TG and vibrating sample magnetometer were used to characterize the magnetic nanomaterials. The results showed that the synthesis of magnetic nanomaterials was successful. The static adsorption method was employed to study the adsorption properties of magnetic nanomaterials towards Cr2O72- and various factors which might influence the adsorption performance of the materials. The optimal conditions for the separation and enrichment environment of heavy chrome acid radical are:acid medium,the temperature is 25℃,potassium dichromate concentration is 0.8 g/L,the adsorption quantity for 120 mg/g,grafting,the greater the amount of adsorption quantity increase.
2013, 30(8): 932-937
doi: 10.3724/SP.J.1095.2013.20361
Abstract:
The adsorption behavior of Cr(Ⅳ) on Mg-Al hydrotalcite compounds(Mg-Al HTlc) was investigated in the metal-organic pollutant system of Cr(Ⅵ) and p-cresol. The results suggest that in the adsorption of Cr(Ⅵ) on HTlc is in the pseudo-second-order reaction and follows Langmuir isothermal adsorption equation;p-cresol can reduce the adsorption velocity but can increase the adsorption capacity of Mg-Al HTlc to adsorb Cr(Ⅵ) from water. Cr(Ⅵ) and p-cresol exhibit a competitive effect. On the one hand,the competitive effect is dependent to the concentration ratio of p-cresol to Cr(Ⅵ),the adsorption capacity of Mg-Al HTlc toward Cr(Ⅵ) can be increased by decreasing the pH value due to the adsorption of p-cresol on HTlc. The competitive ability of p-cresol decreases relatively with the increase of Cr(Ⅵ) concentration and the removal rate of Cr(Ⅵ) increases significantly when the mass concentration ratio of Cr(Ⅵ) to p-cresol is larger than 3. In addition,the adsorption capacity decreases with increasing temperature.
The adsorption behavior of Cr(Ⅳ) on Mg-Al hydrotalcite compounds(Mg-Al HTlc) was investigated in the metal-organic pollutant system of Cr(Ⅵ) and p-cresol. The results suggest that in the adsorption of Cr(Ⅵ) on HTlc is in the pseudo-second-order reaction and follows Langmuir isothermal adsorption equation;p-cresol can reduce the adsorption velocity but can increase the adsorption capacity of Mg-Al HTlc to adsorb Cr(Ⅵ) from water. Cr(Ⅵ) and p-cresol exhibit a competitive effect. On the one hand,the competitive effect is dependent to the concentration ratio of p-cresol to Cr(Ⅵ),the adsorption capacity of Mg-Al HTlc toward Cr(Ⅵ) can be increased by decreasing the pH value due to the adsorption of p-cresol on HTlc. The competitive ability of p-cresol decreases relatively with the increase of Cr(Ⅵ) concentration and the removal rate of Cr(Ⅵ) increases significantly when the mass concentration ratio of Cr(Ⅵ) to p-cresol is larger than 3. In addition,the adsorption capacity decreases with increasing temperature.
2013, 30(8): 938-944
doi: 10.3724/SP.J.1095.2013.20460
Abstract:
Self-cleaning TiO2 films were prepared by hydrothermally treating a microemulsion followed by dipcoating. Effect of the amount of surfactant dodecylbenzenesulfonic acid(DBS) in the microemulsion on the surface morphology and microstructure of TiO2 film was investigated. Photocatalytic activity,photo-induced hydrophilicity and self-cleaning efficiency of the synthesized TiO2 films were evaluated. With the amount of DBS increases,the size of the dispersed TiO2 particle decreases,but the particles tend to agglomerate after hydrothermal treatment. When the amount of DBS is in the range of 0 and 58 mg/L,the resultant TiO2 films consisted of particles with 15~20 nm in diameter are quite smooth. The water contact angles of those films kept in dark increase slowly and their superhydrophilicity can be quickly recovered after irradiation by UV light. The surfaces maintain clean when the films are exposed to outdoor atmosphere for 25 days with their contact angles increasing from 0° to 14°~18°. When the amount of DBS is increased to beyond 580 mg/L,the surfaces of the films become rough and show poor hydrophilicity. The contact angles of the surfaces exposed to outdoor atmosphere for 25 days increase from 0 to 46°~48°.
Self-cleaning TiO2 films were prepared by hydrothermally treating a microemulsion followed by dipcoating. Effect of the amount of surfactant dodecylbenzenesulfonic acid(DBS) in the microemulsion on the surface morphology and microstructure of TiO2 film was investigated. Photocatalytic activity,photo-induced hydrophilicity and self-cleaning efficiency of the synthesized TiO2 films were evaluated. With the amount of DBS increases,the size of the dispersed TiO2 particle decreases,but the particles tend to agglomerate after hydrothermal treatment. When the amount of DBS is in the range of 0 and 58 mg/L,the resultant TiO2 films consisted of particles with 15~20 nm in diameter are quite smooth. The water contact angles of those films kept in dark increase slowly and their superhydrophilicity can be quickly recovered after irradiation by UV light. The surfaces maintain clean when the films are exposed to outdoor atmosphere for 25 days with their contact angles increasing from 0° to 14°~18°. When the amount of DBS is increased to beyond 580 mg/L,the surfaces of the films become rough and show poor hydrophilicity. The contact angles of the surfaces exposed to outdoor atmosphere for 25 days increase from 0 to 46°~48°.
2013, 30(8): 945-950
doi: 10.3724/SP.J.1095.2013.20580
Abstract:
The organotin inorganic complexes(C4H9)3Sn-O-SBA-15[Bu3SnS]were successfully synthesized by grafting tributyltin on SBA-15 mesoporous molecular sieves in a nitrogen atmosphere. The composition,structure and properties of the samples were characterized by X-ray diffraction(XRD),transmittance electron microscopy(TEM),Hammett indicator method,N2 adsorption-desorption,solid nuclear magnetic resonance(NMR),in-situ pyridine infrared spectroscopy(Py-IR) and so on. The results show that the hexagonal P6 mm mesostructure of parent siliceous SBA-15 is maintained in Bu3SnS. The surface areas,proe size and volume of Bu3SnS are all deceased with the increase of acidity,compared to those of SBA-15. Friedel-Crafts acylation of anisole and benzoyl chloride can be efficiently catalyzed in the presence of Bu3SnS. The reaction conversion of anisole and the selectivity of p-benzoylanisole are 76.0% and 97.8%,respectively,when the molar ratio of anisole to benzoyl chloride is 0.5:1.0,the amount of catalyst is 6%,the reaction temperature is 130℃ and the reaction time is 5 h.
The organotin inorganic complexes(C4H9)3Sn-O-SBA-15[Bu3SnS]were successfully synthesized by grafting tributyltin on SBA-15 mesoporous molecular sieves in a nitrogen atmosphere. The composition,structure and properties of the samples were characterized by X-ray diffraction(XRD),transmittance electron microscopy(TEM),Hammett indicator method,N2 adsorption-desorption,solid nuclear magnetic resonance(NMR),in-situ pyridine infrared spectroscopy(Py-IR) and so on. The results show that the hexagonal P6 mm mesostructure of parent siliceous SBA-15 is maintained in Bu3SnS. The surface areas,proe size and volume of Bu3SnS are all deceased with the increase of acidity,compared to those of SBA-15. Friedel-Crafts acylation of anisole and benzoyl chloride can be efficiently catalyzed in the presence of Bu3SnS. The reaction conversion of anisole and the selectivity of p-benzoylanisole are 76.0% and 97.8%,respectively,when the molar ratio of anisole to benzoyl chloride is 0.5:1.0,the amount of catalyst is 6%,the reaction temperature is 130℃ and the reaction time is 5 h.
2013, 30(8): 951-956
doi: 10.3724/SP.J.1095.2013.20447
Abstract:
Polyaniline electrodes doped with quaternary ammonium salts[CnH2n+1N(CH3)3]Cl(n=12,14,16,18) were prepared by cyclic voltammetry. The surface morphology and the structures of composite electrodes were characterized by scanning electron microscope(SEM) and Fourier transform infrared spectroscopy(FTIR). The electrochemical properties of electrodes and the capacitive behavior of the resulting capacitors were systematically studied using cyclic voltammetry(CV),electrochemical impedance spectroscopy(EIS) and constant current charge discharge tests. The specific capacitance of polyaniline electrode doped with[C18H37N(CH3)3]Cl exhibits a value as high as 329.6 F/g,higher than the value of 199.0 F/g for the PANI electrode at a constant current of 2 × 10-3 A. Moreover,the PANI/C18C3 electrodes retain good stability over 30 charge-discharge tests with a specific capacitance of 252.4 F/g.
Polyaniline electrodes doped with quaternary ammonium salts[CnH2n+1N(CH3)3]Cl(n=12,14,16,18) were prepared by cyclic voltammetry. The surface morphology and the structures of composite electrodes were characterized by scanning electron microscope(SEM) and Fourier transform infrared spectroscopy(FTIR). The electrochemical properties of electrodes and the capacitive behavior of the resulting capacitors were systematically studied using cyclic voltammetry(CV),electrochemical impedance spectroscopy(EIS) and constant current charge discharge tests. The specific capacitance of polyaniline electrode doped with[C18H37N(CH3)3]Cl exhibits a value as high as 329.6 F/g,higher than the value of 199.0 F/g for the PANI electrode at a constant current of 2 × 10-3 A. Moreover,the PANI/C18C3 electrodes retain good stability over 30 charge-discharge tests with a specific capacitance of 252.4 F/g.
2013, 30(8): 957-962
doi: 10.3724/SP.J.1095.2013.20470
Abstract:
Three kinds of capillary columns were obtained by coating cyclodextrin derivatives onto inner surface of fused capillary. According to the literature's method,all the theoretical plate numbers are over 2800/m by using n-dodecane,indicating that they have high column efficiencies. Then,separation and mechanism of isomeric benzene derivatives,such as nitrochlorobenzene,nitroaniline,and phenylenediamine by capillary column gas chromatography have been investigated in detail. The interactions such as hydrogen bonding,dipolar-dipolar attraction and π-π stacking between analytes and stationary phases have significant effect on the separation performances of these capillary columns. For phenylenediamine,separation factors on the heptakis(6-azido-6-deoxy-2,3-di-O-p-chlorophenylcarbamoylated)-b-CD (NMCD) and per(pchlorophenylcarbamoylated)-b-CD(ACD) columns are 1.41 and 1.88,respectively,however the positional isomers can not be separated on the NSCD column. For nitrochlorobenzene,the separation factors on the mono(6A-azido-6A-deoxy) per-acetylated-β-CD(NMCD) column are 1.13 and 1.11,respectively,which are very close to those on the ACD column(1.08 and 1.15,respectively),and three positional isomers of nitrochlorobenzene can not be separated on the NSCD column. In addition,the separation of nitroaniline can not be achieved. Meanwhile,the electronic effects derived from different groups of benzene derivatives contribute mainly to the elution order of all the analytes.
Three kinds of capillary columns were obtained by coating cyclodextrin derivatives onto inner surface of fused capillary. According to the literature's method,all the theoretical plate numbers are over 2800/m by using n-dodecane,indicating that they have high column efficiencies. Then,separation and mechanism of isomeric benzene derivatives,such as nitrochlorobenzene,nitroaniline,and phenylenediamine by capillary column gas chromatography have been investigated in detail. The interactions such as hydrogen bonding,dipolar-dipolar attraction and π-π stacking between analytes and stationary phases have significant effect on the separation performances of these capillary columns. For phenylenediamine,separation factors on the heptakis(6-azido-6-deoxy-2,3-di-O-p-chlorophenylcarbamoylated)-b-CD (NMCD) and per(pchlorophenylcarbamoylated)-b-CD(ACD) columns are 1.41 and 1.88,respectively,however the positional isomers can not be separated on the NSCD column. For nitrochlorobenzene,the separation factors on the mono(6A-azido-6A-deoxy) per-acetylated-β-CD(NMCD) column are 1.13 and 1.11,respectively,which are very close to those on the ACD column(1.08 and 1.15,respectively),and three positional isomers of nitrochlorobenzene can not be separated on the NSCD column. In addition,the separation of nitroaniline can not be achieved. Meanwhile,the electronic effects derived from different groups of benzene derivatives contribute mainly to the elution order of all the analytes.
2013, 30(8): 963-970
doi: 10.3724/SP.J.1095.2013.20444
Abstract:
The interactions between chromium cations(Cr2+,Cr3+,Cr6+) and reduced glutathione(GSH) were systematically investigated employing the density functional theory DFT/B3LYP,and the structures of GSH prevalent in both gas and aqueous phases were taken into account. The results showed that:the higher of the charge and smaller of radius of the metal cation are,the larger of the deformation energy of GSH and the binding energy between metal ions and GSH are. The Cr6+ cation might promote the skeleton structure broken and catalyze the decarboxylation reaction of GSH. The interactions between Cr2+ or Cr3+ and GSH in both gas and liquid phase gave nine stable complexes. Comparing with the results gained in gas,the aqueous environment caused a considerable reduction of the binding energies.
The interactions between chromium cations(Cr2+,Cr3+,Cr6+) and reduced glutathione(GSH) were systematically investigated employing the density functional theory DFT/B3LYP,and the structures of GSH prevalent in both gas and aqueous phases were taken into account. The results showed that:the higher of the charge and smaller of radius of the metal cation are,the larger of the deformation energy of GSH and the binding energy between metal ions and GSH are. The Cr6+ cation might promote the skeleton structure broken and catalyze the decarboxylation reaction of GSH. The interactions between Cr2+ or Cr3+ and GSH in both gas and liquid phase gave nine stable complexes. Comparing with the results gained in gas,the aqueous environment caused a considerable reduction of the binding energies.
2013, 30(8): 971-973
doi: 10.3724/SP.J.1095.2013.20530
Abstract:
o-Chlorobenzonitrile was prepared from the cyanization reaction of o-chlorobromobenzene using potassium ferrocyanide as cyanating agent and Pd/C as a catalyst. The reaction conditions were optimized through investigating the reaction temperature,base,the amount of catalyst,the ratio of reactants. The conversion of the o-chlorobromobenzene to target product could reach 98.5% and the yield of o-chlorobenzonitrile was 95.1%.
o-Chlorobenzonitrile was prepared from the cyanization reaction of o-chlorobromobenzene using potassium ferrocyanide as cyanating agent and Pd/C as a catalyst. The reaction conditions were optimized through investigating the reaction temperature,base,the amount of catalyst,the ratio of reactants. The conversion of the o-chlorobromobenzene to target product could reach 98.5% and the yield of o-chlorobenzonitrile was 95.1%.
2013, 30(8): 974-976
doi: 10.3724/SP.J.1095.2013.20575
Abstract:
A novel cardo poly(aryl ether ketone) bearing pendant epoxy group with controlled content(PEKHE) was prepared,by nucleophilic polycondensation from 3,3-bis(4-hydroxyphenyl) benzo pyrrolone(HPP) with 4,4'-diflorobenzophenone,followed by a substitution reaction with epichlorohydrin(ECH). The content of epoxy side group could be controlled via altering the amount of reactant monomer. Structure and properties were characterized and tested by FTIR,1H NMR,TGA,etc. Properties of the PEK-HE coating were investigated after self-curing. Thermal stability of the coating layer was obviously improved compared to that before curing,and 5% mass loss temperature was all over 450℃. The layers had excellent thermal and mechanical properties:heat-resistant temperatures were(350 ± 20)℃,the impact strength were all above 100 kg·cm. Thus the PEK-HE was expected for the application of high performance self-curing coating.
A novel cardo poly(aryl ether ketone) bearing pendant epoxy group with controlled content(PEKHE) was prepared,by nucleophilic polycondensation from 3,3-bis(4-hydroxyphenyl) benzo pyrrolone(HPP) with 4,4'-diflorobenzophenone,followed by a substitution reaction with epichlorohydrin(ECH). The content of epoxy side group could be controlled via altering the amount of reactant monomer. Structure and properties were characterized and tested by FTIR,1H NMR,TGA,etc. Properties of the PEK-HE coating were investigated after self-curing. Thermal stability of the coating layer was obviously improved compared to that before curing,and 5% mass loss temperature was all over 450℃. The layers had excellent thermal and mechanical properties:heat-resistant temperatures were(350 ± 20)℃,the impact strength were all above 100 kg·cm. Thus the PEK-HE was expected for the application of high performance self-curing coating.
