以含有异丙基溴侧基的聚醚醚酮为原子转移自由基聚合(ATRP)大分子引发剂,通过ATRP法在聚醚醚酮主链上接枝引入聚苯乙烯磺酸钠侧链,得到侧链型磺化聚醚醚酮质子交换膜(SSPEEK).采用溶液共混法在SSPEEK膜中引入钠基蒙脱土(Na-MMT),制备SSP...以含有异丙基溴侧基的聚醚醚酮为原子转移自由基聚合(ATRP)大分子引发剂,通过ATRP法在聚醚醚酮主链上接枝引入聚苯乙烯磺酸钠侧链,得到侧链型磺化聚醚醚酮质子交换膜(SSPEEK).采用溶液共混法在SSPEEK膜中引入钠基蒙脱土(Na-MMT),制备SSPEEK/Na-MMT钒电池质子交换复合膜.热重分析表明,复合膜具有较好的耐热性;扫描电镜显示,Na-MMT均匀分散在SSPEEK中.复合膜的钒离子渗透率由SSPEEK膜的1.24×10-5cm2·min-1降为4.88×10-6cm2·min-1,低于Nafion117膜的钒离子渗透率,阻钒能力优于Nafion117膜.电流密度为30 m A·cm-2时,以复合膜组装的电池的放电时间为215 min,长于Nafion117膜的198 min.在高放电电流密度下SSPEEK/Na-MMT膜的库伦效率与Nafion117膜相当.展开更多
The Sodium Montmorillonite(Na-MMT)is not susceptible to polymer due to its organophilic character and low basal spacing.The primary objective of this study was to improve Na-MMT platelets separation by organically mod...The Sodium Montmorillonite(Na-MMT)is not susceptible to polymer due to its organophilic character and low basal spacing.The primary objective of this study was to improve Na-MMT platelets separation by organically modifying it with cation and anion exchanges using Cetyl trimethyl ammonium bromide(CTAB)and Sodium dodecyl sulfate(SDS)respectively.Basal spacing,presence of functional groups,Zetapotential with particle size analysis and thermal stability of the Organomodified Na-MMT(OMMT)were characterized using XRD,FTIR,zeta-potential analyzer and TGA respectively.The basal spacing of CTAB modified OMMTincreased to 19.5Åfrom 11.0Åwhich corresponds to the basal spacing of Na-MMT.The SDS modified OMMT did not show any increase in the basal spacing.FTIR spectra of CTAB modified Na-MMT illustrated the attachment of CTAB functional groups to Na-MMT,while the same was absent in the case of SDS modified Na-MMT.The zeta-potential of Na-MMT shifted from–24.88 mV to 15.66 mV in the case of CTAB modified Na-MMTand 12.49 mV for SDS modified Na-MMT,indicating a greater surface potential of the modified nanoclay.The TGA showed greater weight loss for CTAB modified Na-MMT than that for Na-MMT,indicating the effective Na+ion exchange with alkyl amines.展开更多
Nanocomposites were prepared by a simple technique of emulsion polymerization using VC monomer and Na + montmorillonite. The nano structure of the composites was studied with the aid of X ray diffraction and t ransmis...Nanocomposites were prepared by a simple technique of emulsion polymerization using VC monomer and Na + montmorillonite. The nano structure of the composites was studied with the aid of X ray diffraction and t ransmission electron microscopy,and the mechanical and thermal properties of th e composites were also tested. The results showed that the silicate layers were delam inated or partially exfoliated in the PVC matrix. The impact strength of the mat erial with 2 1% MMT was almost two times as high as that of pure PVC, while the tensi le strength decreased little. However, the mechanical strength of the composites began to decrease with further increasing the amount of MMT. The TGA resul ts showed that the temperature,at which a 50% weight loss of the composites occurred,was higher than that of pure PVC. The vicat softening temperatures of composites were enhanced with increasing MMT content.展开更多
Tetradecyldimethylbenzyl ammonium salt（TDMBA） cations were intercalated into sodium montmorillonite（Na-MMT） by an ion exchange reaction. The resulting TDMBA-MMT was characterized by Fourier-transform infrared spec...Tetradecyldimethylbenzyl ammonium salt（TDMBA） cations were intercalated into sodium montmorillonite（Na-MMT） by an ion exchange reaction. The resulting TDMBA-MMT was characterized by Fourier-transform infrared spectroscopy（FTIR）, thermogravimetric analysis（TGA）, and X-ray diffraction（XRD）. Moreover, the antibacterial activity and water-resistance of TDMBA-MMT were investigated. The results show that TDMBA cations are intercalated into the Na-MMT. The onset temperature of decomposition of TDMBA cations in TDMBA-MMT is raised about 60 ℃ higher than that of tetradecyldimethylbenzyl ammonium chloride（TDMBACl）, and the d（001） spacing enlarged from 1.23 nm to 2.10 nm. 0.1 mg/mL TDMBA-MMT is fully enough to kill all the Staphylococci aureus（S, aureus） and more than 99.99% of the Escherichia coli（E, coli） in a sample solution within 6.0 h touch, and the TDMBA-MMT also shows long acting properties.展开更多
文摘以含有异丙基溴侧基的聚醚醚酮为原子转移自由基聚合(ATRP)大分子引发剂,通过ATRP法在聚醚醚酮主链上接枝引入聚苯乙烯磺酸钠侧链,得到侧链型磺化聚醚醚酮质子交换膜(SSPEEK).采用溶液共混法在SSPEEK膜中引入钠基蒙脱土(Na-MMT),制备SSPEEK/Na-MMT钒电池质子交换复合膜.热重分析表明,复合膜具有较好的耐热性;扫描电镜显示,Na-MMT均匀分散在SSPEEK中.复合膜的钒离子渗透率由SSPEEK膜的1.24×10-5cm2·min-1降为4.88×10-6cm2·min-1,低于Nafion117膜的钒离子渗透率,阻钒能力优于Nafion117膜.电流密度为30 m A·cm-2时,以复合膜组装的电池的放电时间为215 min,长于Nafion117膜的198 min.在高放电电流密度下SSPEEK/Na-MMT膜的库伦效率与Nafion117膜相当.
文摘The Sodium Montmorillonite(Na-MMT)is not susceptible to polymer due to its organophilic character and low basal spacing.The primary objective of this study was to improve Na-MMT platelets separation by organically modifying it with cation and anion exchanges using Cetyl trimethyl ammonium bromide(CTAB)and Sodium dodecyl sulfate(SDS)respectively.Basal spacing,presence of functional groups,Zetapotential with particle size analysis and thermal stability of the Organomodified Na-MMT(OMMT)were characterized using XRD,FTIR,zeta-potential analyzer and TGA respectively.The basal spacing of CTAB modified OMMTincreased to 19.5Åfrom 11.0Åwhich corresponds to the basal spacing of Na-MMT.The SDS modified OMMT did not show any increase in the basal spacing.FTIR spectra of CTAB modified Na-MMT illustrated the attachment of CTAB functional groups to Na-MMT,while the same was absent in the case of SDS modified Na-MMT.The zeta-potential of Na-MMT shifted from–24.88 mV to 15.66 mV in the case of CTAB modified Na-MMTand 12.49 mV for SDS modified Na-MMT,indicating a greater surface potential of the modified nanoclay.The TGA showed greater weight loss for CTAB modified Na-MMT than that for Na-MMT,indicating the effective Na+ion exchange with alkyl amines.
文摘Nanocomposites were prepared by a simple technique of emulsion polymerization using VC monomer and Na + montmorillonite. The nano structure of the composites was studied with the aid of X ray diffraction and t ransmission electron microscopy,and the mechanical and thermal properties of th e composites were also tested. The results showed that the silicate layers were delam inated or partially exfoliated in the PVC matrix. The impact strength of the mat erial with 2 1% MMT was almost two times as high as that of pure PVC, while the tensi le strength decreased little. However, the mechanical strength of the composites began to decrease with further increasing the amount of MMT. The TGA resul ts showed that the temperature,at which a 50% weight loss of the composites occurred,was higher than that of pure PVC. The vicat softening temperatures of composites were enhanced with increasing MMT content.
基金Supported by the National Natural Science Fundation of China(Nos.20676049,20871058 and 20971028)the Foundation of Enterprise-University-Research Institute Cooperation from Guangdong Province and Ministry of Education of China(Nos. 2007B090400105 and 2008A010500005)
文摘Tetradecyldimethylbenzyl ammonium salt（TDMBA） cations were intercalated into sodium montmorillonite（Na-MMT） by an ion exchange reaction. The resulting TDMBA-MMT was characterized by Fourier-transform infrared spectroscopy（FTIR）, thermogravimetric analysis（TGA）, and X-ray diffraction（XRD）. Moreover, the antibacterial activity and water-resistance of TDMBA-MMT were investigated. The results show that TDMBA cations are intercalated into the Na-MMT. The onset temperature of decomposition of TDMBA cations in TDMBA-MMT is raised about 60 ℃ higher than that of tetradecyldimethylbenzyl ammonium chloride（TDMBACl）, and the d（001） spacing enlarged from 1.23 nm to 2.10 nm. 0.1 mg/mL TDMBA-MMT is fully enough to kill all the Staphylococci aureus（S, aureus） and more than 99.99% of the Escherichia coli（E, coli） in a sample solution within 6.0 h touch, and the TDMBA-MMT also shows long acting properties.
