Mixed matrix hollow fiber membranes（MMHFMs）filled with metal-organic frameworks（MOFs）have great potential for energy-efficient gas separation processes,but the major hurdle is polymer/MOFs interfacial defects and ...Mixed matrix hollow fiber membranes（MMHFMs）filled with metal-organic frameworks（MOFs）have great potential for energy-efficient gas separation processes,but the major hurdle is polymer/MOFs interfacial defects and membrane plasticization.Herein,lab-synthesized MIL-53 was post-functionalized by aminosilane grafting and subsequently incorporated into Ultem-1000 polymer matrix to fabricate high performance MMHFMs.SEM,DLS,XRD and TGA were performed to characterize silane-modified MIL-53（S-MIL-53）and prepared MMHFMs.Moreover,the effect of MOFs loading was systematically investigated first;then gas separation performance of MMHFMs for pure and mixed gas was evaluated under different pressures.MMHFMs containing post-functionalized S-MIL-53 achieved remarkable gas permeation properties which was better than model predictions.Compared to pure HFMs,CO2permeance of MMHFM loaded with 15%S-MIL-53 increased by 157%accompanying with 40%increase for CO2/N2selectivity,which outperformed the MMHFM filled with naked MIL-53.The pure and mixed gas permeation measurements with elevated feed pressure indicated that incorporation of S-MIL-53 also increased the resistance against CO2plasticization.This work reveals that post-modified MOFs embedded in MMHFMs facilitate the improvement of gas separation performance and suppression of membrane plasticization.展开更多
Chemoselective,living/controlled polymerizations of allyl methacrylate(AMA) and vinyl methacrylate(VMA) with/without methyl methacrylate(MMA) by using the phosphonium ylide/organoaluminum based Lewis pairs(LPs) have b...Chemoselective,living/controlled polymerizations of allyl methacrylate(AMA) and vinyl methacrylate(VMA) with/without methyl methacrylate(MMA) by using the phosphonium ylide/organoaluminum based Lewis pairs(LPs) have been realized.The P-ylide-2/AIMe(BHT)_(2)(Pylide-2=Ph_(3)P=CHMe and BHT=2,6-iBu_(2)-4-MeC_(6)H_(2)O) was demonstrated to be superior by which homopolymers PAMAs(M_(n)=27.6-111.5kg/mol and ■=1.14-1.25) and PVMAs(M_(n)=28.4-78.4 kg/mol and ■=1.12-1.18) and block copolymers PMMA-b-PAMA,PAMA-b-PVMA,PAMA-bPMMA,PMMA-b-PAMA-b-PMMA,PAMA-b-PMMA-b-PAMA,and PAMA-b-PVMA-b-PAMA were synthesized.In the polymerizations,all of the monomers were reacted by the conjugated ester vinyl groups leaving intactly the nonconjugated acryloxy groups.The pendant acryloxy groups attached to the main chain enable further to post-functionalization by the AIBN-induced radical "thiol-ene" reaction using PhCH_(2)SH.The thiolether side group-containing polymers PAMA-SCH_(2)Ph and PAMA-SCH_(2)Ph-b-PMMA-b-PAMA-SCH_(2)Ph were thus prepared.展开更多
以十氟联苯、双酚A低温聚合制备可高温官能化的聚合物主链,以3,5-二甲基苯酚为功能侧链,采用后官能化工艺制备了系列不同离子交换容量(IEC)值的含侧链苄基季铵基团的部分氟化阴离子交换膜.用GPC、1H-NMR、19F-NMR、IR、SASX等表征了膜...以十氟联苯、双酚A低温聚合制备可高温官能化的聚合物主链,以3,5-二甲基苯酚为功能侧链,采用后官能化工艺制备了系列不同离子交换容量(IEC)值的含侧链苄基季铵基团的部分氟化阴离子交换膜.用GPC、1H-NMR、19F-NMR、IR、SASX等表征了膜的分子结构及聚集态结构,并且测试了膜的各种性能.结果表明,该系列部分氟化阴离子交换膜的分子主链线性好,官能度可控,具有明显的微相分离结构.部分氟化结构和微相分离的侧链离子结构极大的改善了膜的吸水溶胀性、电导率和化学稳定性.QFPAE-95膜具有最高的氢氧根离子电导率和适度吸水溶胀性,80oC时离子电导率和溶胀比分别达到108.6 m S cm-1和42.6%.QFPAE-55具有最大的拉伸强度,达到21.01 MPa.该系列膜还具有出色的碱稳定性,QFPAE-55膜在1 mol/L Na OH溶液中于60oC下浸泡20天后,其电导率和IEC值分别保持为原膜的82.3%和84.2%,有望作为新型阴离子交换膜并应用于碱性膜燃料电池.展开更多
As an emerging and efficient polymerization methodology,activated internal alkyne-based polymerization has been considered as a powerful tool for the construction of polymers with diverse architectures and versatile f...As an emerging and efficient polymerization methodology,activated internal alkyne-based polymerization has been considered as a powerful tool for the construction of polymers with diverse architectures and versatile functions.This review focuses on the recent progresses in the polymerization using mono-activated,di-activated,in-situ generated,ring-strained ethynyl groups as substrates,coupling with post-modification on premade polymers containing activated internal ethynyl moieties.Representative examples are used to illustrate the fundamental design strategy,the development of polymerization and post-functionalization,along with the properties and potential applications of the prepared polymers.Moreover,the challenges and perspectives in terms of new-type active alkynes,green polymerization methodology,tailored regio-/stereoselectivity modulation,and potentially expanded application in this area are also discussed.展开更多
Main observation and conclusion In this paper,two novel donor-acceptor(D-A)macrocyclic compounds 5 and 7 were successfully synthesized by post-functionalization of a planar dimer macrocycle(1)and a highly twisted trim...Main observation and conclusion In this paper,two novel donor-acceptor(D-A)macrocyclic compounds 5 and 7 were successfully synthesized by post-functionalization of a planar dimer macrocycle(1)and a highly twisted trimer macrocycle(2),respectively,via controllable oxidation of methoxy groups and condensation between diketones and phenylenediamine in succession.Compared with unembellished 9,10-dimethoxyphenanthrene,the resultant dibenzo[a,c]phenazine motif is electron-deficient rather than electron-rich,yielding two D-Aπ-conjugated macrocycles with more contractive energy gaps.Density functional theory(DFT)calculations further support the unequivocal evidence of the D-A properties of macrocycles 5 and 7.The difference of their photophysical properties was investigated by the aid of ultraviolet-visible absorption and fluorescence spectrophotometers.Furthermore,the stacking patterns of 7 and its contrastπ-conjugated macrocycle trimer(2)were compared via the analysis of X-ray single crystal,in which the electron-deficient dibenzo[a,c]phenazine unit provides extra interaction sites,resulting in orderly arrangement of 7 in the solid state.展开更多
Surface design and engineering is a critical tool to improve the interaction of materials with their surroundings. Immobilization of soft hydrogels is one of the attractive strategies to achieve surface modification. ...Surface design and engineering is a critical tool to improve the interaction of materials with their surroundings. Immobilization of soft hydrogels is one of the attractive strategies to achieve surface modification. The goal of this review is to provide a comprehensive overview of the different strategies used for surface tethering of hydrogel layers via crosslinking immobilization of pre-fabricated functional polymers. In this strategy, crosslinkable polymers are first prepared via various polymerization techniques or post-functionalization of polymers. Afterwards, the crosslinkable polymers are attached or tethered on the surfaces of substrates using a variety of approaches including photo-crosslinking, click reactions, reversible linkages, etc. For each case, the principles of hydrogel tethering have been explained in detail with representative examples.Moreover, the potential applications of the as-modified substrates in specific cases have also been addressed and overviewed.展开更多
基金the financial support from the National Natural Science Foundation of China(No.21436009)
文摘Mixed matrix hollow fiber membranes（MMHFMs）filled with metal-organic frameworks（MOFs）have great potential for energy-efficient gas separation processes,but the major hurdle is polymer/MOFs interfacial defects and membrane plasticization.Herein,lab-synthesized MIL-53 was post-functionalized by aminosilane grafting and subsequently incorporated into Ultem-1000 polymer matrix to fabricate high performance MMHFMs.SEM,DLS,XRD and TGA were performed to characterize silane-modified MIL-53（S-MIL-53）and prepared MMHFMs.Moreover,the effect of MOFs loading was systematically investigated first;then gas separation performance of MMHFMs for pure and mixed gas was evaluated under different pressures.MMHFMs containing post-functionalized S-MIL-53 achieved remarkable gas permeation properties which was better than model predictions.Compared to pure HFMs,CO2permeance of MMHFM loaded with 15%S-MIL-53 increased by 157%accompanying with 40%increase for CO2/N2selectivity,which outperformed the MMHFM filled with naked MIL-53.The pure and mixed gas permeation measurements with elevated feed pressure indicated that incorporation of S-MIL-53 also increased the resistance against CO2plasticization.This work reveals that post-modified MOFs embedded in MMHFMs facilitate the improvement of gas separation performance and suppression of membrane plasticization.
基金financially supported by the National Natural Science Foundation of China (Nos. 21972112 and 22225104)China Postdoctoral Science Foundation (Nos. 2022TQ0115 and 2022M711297)。
文摘Chemoselective,living/controlled polymerizations of allyl methacrylate(AMA) and vinyl methacrylate(VMA) with/without methyl methacrylate(MMA) by using the phosphonium ylide/organoaluminum based Lewis pairs(LPs) have been realized.The P-ylide-2/AIMe(BHT)_(2)(Pylide-2=Ph_(3)P=CHMe and BHT=2,6-iBu_(2)-4-MeC_(6)H_(2)O) was demonstrated to be superior by which homopolymers PAMAs(M_(n)=27.6-111.5kg/mol and ■=1.14-1.25) and PVMAs(M_(n)=28.4-78.4 kg/mol and ■=1.12-1.18) and block copolymers PMMA-b-PAMA,PAMA-b-PVMA,PAMA-bPMMA,PMMA-b-PAMA-b-PMMA,PAMA-b-PMMA-b-PAMA,and PAMA-b-PVMA-b-PAMA were synthesized.In the polymerizations,all of the monomers were reacted by the conjugated ester vinyl groups leaving intactly the nonconjugated acryloxy groups.The pendant acryloxy groups attached to the main chain enable further to post-functionalization by the AIBN-induced radical "thiol-ene" reaction using PhCH_(2)SH.The thiolether side group-containing polymers PAMA-SCH_(2)Ph and PAMA-SCH_(2)Ph-b-PMMA-b-PAMA-SCH_(2)Ph were thus prepared.
基金Natural Science Youth Foundation of Henan Province(202300410032)Key Scientific Research Projects of Colleges and Universities of Henan Provincial Department of Education(21A150010)Foundation for University Key Teacher by the Henan University of Urban Construction(YCJQNGGJS202109).
文摘以十氟联苯、双酚A低温聚合制备可高温官能化的聚合物主链,以3,5-二甲基苯酚为功能侧链,采用后官能化工艺制备了系列不同离子交换容量(IEC)值的含侧链苄基季铵基团的部分氟化阴离子交换膜.用GPC、1H-NMR、19F-NMR、IR、SASX等表征了膜的分子结构及聚集态结构,并且测试了膜的各种性能.结果表明,该系列部分氟化阴离子交换膜的分子主链线性好,官能度可控,具有明显的微相分离结构.部分氟化结构和微相分离的侧链离子结构极大的改善了膜的吸水溶胀性、电导率和化学稳定性.QFPAE-95膜具有最高的氢氧根离子电导率和适度吸水溶胀性,80oC时离子电导率和溶胀比分别达到108.6 m S cm-1和42.6%.QFPAE-55具有最大的拉伸强度,达到21.01 MPa.该系列膜还具有出色的碱稳定性,QFPAE-55膜在1 mol/L Na OH溶液中于60oC下浸泡20天后,其电导率和IEC值分别保持为原膜的82.3%和84.2%,有望作为新型阴离子交换膜并应用于碱性膜燃料电池.
基金supported by the National Natural Science Foundation of China(21788102,21901075,22001078)the Natural Science Foundation of Guangdong Province(2016A030312002,2019B030301003)the Innovation and Technology Commission of Hong Kong(ITCCNERC14S01).
文摘As an emerging and efficient polymerization methodology,activated internal alkyne-based polymerization has been considered as a powerful tool for the construction of polymers with diverse architectures and versatile functions.This review focuses on the recent progresses in the polymerization using mono-activated,di-activated,in-situ generated,ring-strained ethynyl groups as substrates,coupling with post-modification on premade polymers containing activated internal ethynyl moieties.Representative examples are used to illustrate the fundamental design strategy,the development of polymerization and post-functionalization,along with the properties and potential applications of the prepared polymers.Moreover,the challenges and perspectives in terms of new-type active alkynes,green polymerization methodology,tailored regio-/stereoselectivity modulation,and potentially expanded application in this area are also discussed.
基金supported by the Hong Kong Research Grants Council(HKU 27301720).J.L.is grateful for the funding support from ITC to the S.K.L.We thank the UGC funding administered by The University of Hong Kong(HKU)supporting the Time-of-Flight Mass Spectrometry Facilities under the Support for Interdisciplinary Research in Chemical Science,and HKU University Development Fund for funding the X-Ray Diffractometer Facilities.We acknowledge the computer cluster(HPC2015)HKU for generous allocations of compute resources.
文摘Main observation and conclusion In this paper,two novel donor-acceptor(D-A)macrocyclic compounds 5 and 7 were successfully synthesized by post-functionalization of a planar dimer macrocycle(1)and a highly twisted trimer macrocycle(2),respectively,via controllable oxidation of methoxy groups and condensation between diketones and phenylenediamine in succession.Compared with unembellished 9,10-dimethoxyphenanthrene,the resultant dibenzo[a,c]phenazine motif is electron-deficient rather than electron-rich,yielding two D-Aπ-conjugated macrocycles with more contractive energy gaps.Density functional theory(DFT)calculations further support the unequivocal evidence of the D-A properties of macrocycles 5 and 7.The difference of their photophysical properties was investigated by the aid of ultraviolet-visible absorption and fluorescence spectrophotometers.Furthermore,the stacking patterns of 7 and its contrastπ-conjugated macrocycle trimer(2)were compared via the analysis of X-ray single crystal,in which the electron-deficient dibenzo[a,c]phenazine unit provides extra interaction sites,resulting in orderly arrangement of 7 in the solid state.
基金financially supported by Provincial Key Lab of Pulp and Paper Science and Technology and Joint International Research Lab of Lignocellulosic Functional Materials,Nanjing Forestry University,the National Nature Science Foundation of China(Nos.31730106 and 31770623)NSERC Canada。
文摘Surface design and engineering is a critical tool to improve the interaction of materials with their surroundings. Immobilization of soft hydrogels is one of the attractive strategies to achieve surface modification. The goal of this review is to provide a comprehensive overview of the different strategies used for surface tethering of hydrogel layers via crosslinking immobilization of pre-fabricated functional polymers. In this strategy, crosslinkable polymers are first prepared via various polymerization techniques or post-functionalization of polymers. Afterwards, the crosslinkable polymers are attached or tethered on the surfaces of substrates using a variety of approaches including photo-crosslinking, click reactions, reversible linkages, etc. For each case, the principles of hydrogel tethering have been explained in detail with representative examples.Moreover, the potential applications of the as-modified substrates in specific cases have also been addressed and overviewed.
