Dimethyl carbonate(DMC)is a crucial chemical raw material widely used in organic synthesis,lithiumion battery electrolytes,and various other fields.The current primary industrial process employs a conventional sodium ...Dimethyl carbonate(DMC)is a crucial chemical raw material widely used in organic synthesis,lithiumion battery electrolytes,and various other fields.The current primary industrial process employs a conventional sodium methoxide basic catalyst to produce DMC through the transesterification reaction between vinyl carbonate and methanol.However,the utilization of this catalyst presents several challenges during the process,including equipment corrosion,the generation of solid waste,susceptibility to deactivation,and complexities in separation and recovery.To address these limitations,a series of alkaline poly(ionic liquid)s,i.e.[DVBPIL][PHO],[DVCPIL][PHO],and[TBVPIL][PHO],with different crosslinking degrees and structures,were synthesized through the construction of cross-linked polymeric monomers and functionalization.These poly(ionic liquid)s exhibit cross-linked structures and controllable cationic and anionic characteristics.Research was conducted to investigate the effect of the cross-linking degree and structure on the catalytic performance of transesterification in synthesizing DMC.It was discovered that the appropriate cross-linking degree and structure of the[DVCPIL][PHO]catalyst resulted in a DMC yield of up to 80.6%.Furthermore,this catalyst material exhibited good stability,maintaining its catalytic activity after repeated use five times without significant changes.The results of this study demonstrate the potential for using alkaline poly(ionic liquid)s as a highly efficient and sustainable alternative to traditional catalysts for the transesterification synthesis of DMC.展开更多
In order to reduce the hazard of coal spontaneous combustion,the cross-linking reaction between O-containing functional groups of coal should be inhibited.So the inhibitory effect of an ionic liquid(IL) on the cross-l...In order to reduce the hazard of coal spontaneous combustion,the cross-linking reaction between O-containing functional groups of coal should be inhibited.So the inhibitory effect of an ionic liquid(IL) on the cross-linking reaction was studied.The O-containing functional groups change the weight loss and H_2O,CO_2,CO yields of bituminous coal before and after[H0Emim][BF_4]and[Amim]Cl pre-treatment and were detected by Fourier Transform Infrared spectroscopy(FT1R) and Thermo Gravimetric(TC) analysis.The results show that | AmimjCI has a weaker ability to inhibit the cross-linking reaction of bituminous coal compared to[HOEmim][BF_4].Besides,based on Quantum Chemistry calculation,it was found that the different inhibiting effects of |H0Emim][BF_4]and[Amim]Cl are greatly related to their anions and the H linked with C2 atom on the imidazole ring.The H-donor ability of coal will be enhanced by[HOEmim][BF_4]leading to a weaker cross-linking reaction of coal.展开更多
An appropriate amount of toluene 2,4-diisocyanate（TDI） was added into polyether（[（CH2CH2O）13 CH2O]n/Li salt electrolyte to form a cross-linked network,with improving the film proces sability and thermal stability...An appropriate amount of toluene 2,4-diisocyanate（TDI） was added into polyether（[（CH2CH2O）13 CH2O]n/Li salt electrolyte to form a cross-linked network,with improving the film proces sability and thermal stability.The relation between the structure and ioinc conductive properties of the cross-lined polyether electrolytes was investigated by means of Fourier transform infra-red spectroscopy（FTIR）,differential scanning calorimetry（DSC）,mechanical property and AC impedance spectroscopy.The electrolytes system is found to have two glass transitions,and it is found that the two Tgs increase with increasing salt concentration.At the some Li salt concentration,the conductivity of cross-liked polyether/LiN（CF3SO2）2 complex system is higher than that of LiClo4,At EO/Li=25：1（mol ratio）,the former conductivity changes with temperature,while the later coincids with Arrhenius formula（σ=Ae^-Ea/RT）.The cross-linked polyether/LiN（CF3 SO2）2 electrolyte exhibits the maximum σ=10^-4.75S/cm at 30℃.展开更多
Flexible sensors that can respond to multiple mechanical excitation modes and have high sensitivity are of great significance in the fields of electronic skin and health monitoring.Simulating multiple signal responses...Flexible sensors that can respond to multiple mechanical excitation modes and have high sensitivity are of great significance in the fields of electronic skin and health monitoring.Simulating multiple signal responses to skin such as strain and temperature remains an important challenge.Therefore,new multifunctional ion-crosslinked hydrogels with toughness and conductivity were designed and prepared in this work.A chemical gel with high mechanical strength was prepared by cross-linking acrylamide with N,N’-methylenebisacrylamide and ammonium persulfate.In addition,in order to enhance the conductive properties of the hydrogel,Ca^(2+),Mg^(2+)and Al^(3+)ions were added to the hydrogel during crosslinking.The double-layer network makes this ionic hydrogel show excellent mechanical properties.Moreover,the composite hydrogel containing Ca^(2+)can reach a maximum stretch of 1100%and exhibits ultra-high sensitivity(Sp=10.690 MPa^(-1)).The obtained hydrogels can successfully prepare wearable strain sensors,as well as track and monitor human motion.The present prepared multifunctional hydrogels are expected to be further expanded to intelligent health sensor materials.展开更多
Ionic skin(I-skin)is an emerging skin-inspired sensor that has received increasing interest for the next-generation wearable electronics.However,profound challenges for I-skin remain in achieving multiple signal respo...Ionic skin(I-skin)is an emerging skin-inspired sensor that has received increasing interest for the next-generation wearable electronics.However,profound challenges for I-skin remain in achieving multiple signal responses(e.g.,strain,pressure,and humidity)and self-healability to fully mimic human skin.Herein,a Fe;ion-coordinated poly(acrylic acid)ionogel(PAIFe)with high stretchability,extreme temperature tolerance,and self-healing capability is prepared by a dynamic ionic cross-linking strategy.The ionic coordination in the PAIFe contributes to the formation of a highly dynamic network,achieving its high-efficient and reliable self-healing performance even at a low temperature of-20℃.Using of 1-butyl-3-methylimidazolium tetrafluoroborate([BMIm][BF^(3+)])as the solvent achieves a widetemperature tolerance of the PAIFe under low and high temperatures.More interestingly,a humidity sensing function is realized in the PAIFe by skillfully utilizing the hygroscopic properties of[BMIm][BF_(4)].The resultant PAIFe is proof-ofconcept demonstrated as a deformation-tolerant ionic conductor in a skin-inspired ionic sensor,showing a variety of sensory capabilities towards compression,strain and humidity.展开更多
In recent years,remarkable progress has been made in the research of injectable hydrogel for internal tissue healing.However,the therapeutic outcome is usually limited when the hydrogel is used for the treatment of ga...In recent years,remarkable progress has been made in the research of injectable hydrogel for internal tissue healing.However,the therapeutic outcome is usually limited when the hydrogel is used for the treatment of gastric perforation due to the high acidic gastric juice and violent deformation of the gastric wall.Regarding these challenges,we proposed an ionic nano-reservoir(INR)-based dual-network hydrogel,which has excellent adhesion and mechanical properties,and can be easily applied to the perforation site to block the perforation while promoting tissue repairing.The results showed that the first network made of polyacrylamide had cross-linked on the stomach tissue within 5 s under blue light,and enhanced the adhesion performance through mechanical interlock.The nano-hydroxyapatite acted as ionic INR,which can gradually release Ca^(2+) under acid environments to form the second network with sodium alginate and inhibit the swelling of hydrogel in gastric juice.Meanwhile,the adhesion was further enhanced through amide covalent bonds at the hydrogel-tissue interface with the presence of 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide/N-hydroxysuccinimide(EDC/NHS).The dual network hydrogels obtained by the INR strategy could be employed as a potential therapeutic option for gastric perforation and other similar biomedical prolems.展开更多
The present study describes the facile preparation of acid/CO2 stimuliresponsive sheddable nanoparticles based on carboxymethylated chitosan(CMCS).Commercially available CMCS was grafted with monomethoxy polyethylene ...The present study describes the facile preparation of acid/CO2 stimuliresponsive sheddable nanoparticles based on carboxymethylated chitosan(CMCS).Commercially available CMCS was grafted with monomethoxy polyethylene glycol(mPEG)chains via an acid/CO2 responsive linker,i.e.,benzoic-imine,and then was used for the cross-linking with CaCI2.With a high CMCS concentration up to 7 mg/mL,stable nanoparticles were successfully prepared.The particle size grew slightly with increasing the molecular weight of mPEG.When the concentration of CaCI2 and the feed ratio of CMCS to mPEG increased,the particle size decreased at first and then increased after reaching a minimum size.When the particles were stimulated by CO2 or acid,benzoic.imine cleaved quickly,and mPEG fell off the nanoparticles simultaneously,and then flocculation and precipitation occurred.These sheddable nanoparticles might have potential application in the biomedical field in eluding the intelligent drug delivery system.展开更多
基金supported by the National Key Research and Development Program of China(2022YFB4101800)National Natural Science Foundation of China(22278077,22108040)+2 种基金Key Program of Qingyuan Innovation Laboratory(00221004)Research Program of Qingyuan Innovation Laboratory(00523006)Natural Science Foundation of Fujian Province(2022J02019)。
文摘Dimethyl carbonate(DMC)is a crucial chemical raw material widely used in organic synthesis,lithiumion battery electrolytes,and various other fields.The current primary industrial process employs a conventional sodium methoxide basic catalyst to produce DMC through the transesterification reaction between vinyl carbonate and methanol.However,the utilization of this catalyst presents several challenges during the process,including equipment corrosion,the generation of solid waste,susceptibility to deactivation,and complexities in separation and recovery.To address these limitations,a series of alkaline poly(ionic liquid)s,i.e.[DVBPIL][PHO],[DVCPIL][PHO],and[TBVPIL][PHO],with different crosslinking degrees and structures,were synthesized through the construction of cross-linked polymeric monomers and functionalization.These poly(ionic liquid)s exhibit cross-linked structures and controllable cationic and anionic characteristics.Research was conducted to investigate the effect of the cross-linking degree and structure on the catalytic performance of transesterification in synthesizing DMC.It was discovered that the appropriate cross-linking degree and structure of the[DVCPIL][PHO]catalyst resulted in a DMC yield of up to 80.6%.Furthermore,this catalyst material exhibited good stability,maintaining its catalytic activity after repeated use five times without significant changes.The results of this study demonstrate the potential for using alkaline poly(ionic liquid)s as a highly efficient and sustainable alternative to traditional catalysts for the transesterification synthesis of DMC.
基金the support from the National Natural Science Foundation of China(Nos.51304073and 51304071)the Educational Commission of Henan Province(Nos.13A440324 and 12B440004)+1 种基金the Open Projects of State Key Laboratory of Coal Resources and Safe Mining,China University of Mining and Technology(No.12KF02)Henan Polytechnic University(Nos.B2012-068 and B2012-085)
文摘In order to reduce the hazard of coal spontaneous combustion,the cross-linking reaction between O-containing functional groups of coal should be inhibited.So the inhibitory effect of an ionic liquid(IL) on the cross-linking reaction was studied.The O-containing functional groups change the weight loss and H_2O,CO_2,CO yields of bituminous coal before and after[H0Emim][BF_4]and[Amim]Cl pre-treatment and were detected by Fourier Transform Infrared spectroscopy(FT1R) and Thermo Gravimetric(TC) analysis.The results show that | AmimjCI has a weaker ability to inhibit the cross-linking reaction of bituminous coal compared to[HOEmim][BF_4].Besides,based on Quantum Chemistry calculation,it was found that the different inhibiting effects of |H0Emim][BF_4]and[Amim]Cl are greatly related to their anions and the H linked with C2 atom on the imidazole ring.The H-donor ability of coal will be enhanced by[HOEmim][BF_4]leading to a weaker cross-linking reaction of coal.
文摘An appropriate amount of toluene 2,4-diisocyanate（TDI） was added into polyether（[（CH2CH2O）13 CH2O]n/Li salt electrolyte to form a cross-linked network,with improving the film proces sability and thermal stability.The relation between the structure and ioinc conductive properties of the cross-lined polyether electrolytes was investigated by means of Fourier transform infra-red spectroscopy（FTIR）,differential scanning calorimetry（DSC）,mechanical property and AC impedance spectroscopy.The electrolytes system is found to have two glass transitions,and it is found that the two Tgs increase with increasing salt concentration.At the some Li salt concentration,the conductivity of cross-liked polyether/LiN（CF3SO2）2 complex system is higher than that of LiClo4,At EO/Li=25：1（mol ratio）,the former conductivity changes with temperature,while the later coincids with Arrhenius formula（σ=Ae^-Ea/RT）.The cross-linked polyether/LiN（CF3 SO2）2 electrolyte exhibits the maximum σ=10^-4.75S/cm at 30℃.
基金the National Natural Science Foundation of China(21872119 and 22072127)the Talent Engineering Training Funding Project of Hebei Province(A201905004)+1 种基金the Research Program of the College Science and Technology of Hebei Province(ZD2018091)Hebei Province Graduate Innovation Funding Project(CXZZSS2020047)。
文摘Flexible sensors that can respond to multiple mechanical excitation modes and have high sensitivity are of great significance in the fields of electronic skin and health monitoring.Simulating multiple signal responses to skin such as strain and temperature remains an important challenge.Therefore,new multifunctional ion-crosslinked hydrogels with toughness and conductivity were designed and prepared in this work.A chemical gel with high mechanical strength was prepared by cross-linking acrylamide with N,N’-methylenebisacrylamide and ammonium persulfate.In addition,in order to enhance the conductive properties of the hydrogel,Ca^(2+),Mg^(2+)and Al^(3+)ions were added to the hydrogel during crosslinking.The double-layer network makes this ionic hydrogel show excellent mechanical properties.Moreover,the composite hydrogel containing Ca^(2+)can reach a maximum stretch of 1100%and exhibits ultra-high sensitivity(Sp=10.690 MPa^(-1)).The obtained hydrogels can successfully prepare wearable strain sensors,as well as track and monitor human motion.The present prepared multifunctional hydrogels are expected to be further expanded to intelligent health sensor materials.
基金financially supported by the National Natural Science Foundation of China(21875033 and 52122303)。
文摘Ionic skin(I-skin)is an emerging skin-inspired sensor that has received increasing interest for the next-generation wearable electronics.However,profound challenges for I-skin remain in achieving multiple signal responses(e.g.,strain,pressure,and humidity)and self-healability to fully mimic human skin.Herein,a Fe;ion-coordinated poly(acrylic acid)ionogel(PAIFe)with high stretchability,extreme temperature tolerance,and self-healing capability is prepared by a dynamic ionic cross-linking strategy.The ionic coordination in the PAIFe contributes to the formation of a highly dynamic network,achieving its high-efficient and reliable self-healing performance even at a low temperature of-20℃.Using of 1-butyl-3-methylimidazolium tetrafluoroborate([BMIm][BF^(3+)])as the solvent achieves a widetemperature tolerance of the PAIFe under low and high temperatures.More interestingly,a humidity sensing function is realized in the PAIFe by skillfully utilizing the hygroscopic properties of[BMIm][BF_(4)].The resultant PAIFe is proof-ofconcept demonstrated as a deformation-tolerant ionic conductor in a skin-inspired ionic sensor,showing a variety of sensory capabilities towards compression,strain and humidity.
基金supported by the National Natural Science Foundation of China(81971701,51832001,and 81901873)the Natural Science Foundation of Jiangsu Province(BK20201352)the Program of Jiangsu Specially-Appointed Professor。
文摘In recent years,remarkable progress has been made in the research of injectable hydrogel for internal tissue healing.However,the therapeutic outcome is usually limited when the hydrogel is used for the treatment of gastric perforation due to the high acidic gastric juice and violent deformation of the gastric wall.Regarding these challenges,we proposed an ionic nano-reservoir(INR)-based dual-network hydrogel,which has excellent adhesion and mechanical properties,and can be easily applied to the perforation site to block the perforation while promoting tissue repairing.The results showed that the first network made of polyacrylamide had cross-linked on the stomach tissue within 5 s under blue light,and enhanced the adhesion performance through mechanical interlock.The nano-hydroxyapatite acted as ionic INR,which can gradually release Ca^(2+) under acid environments to form the second network with sodium alginate and inhibit the swelling of hydrogel in gastric juice.Meanwhile,the adhesion was further enhanced through amide covalent bonds at the hydrogel-tissue interface with the presence of 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide/N-hydroxysuccinimide(EDC/NHS).The dual network hydrogels obtained by the INR strategy could be employed as a potential therapeutic option for gastric perforation and other similar biomedical prolems.
基金This work was supported by the Natural Science Foundation of Hubei Province(2016CFB329)the Science and Technology Research Program of Hubei Provincial Department of Education(B2016260)the Scientific Research and Technological Development Program of Jingmen City(YFYB2016021).
文摘The present study describes the facile preparation of acid/CO2 stimuliresponsive sheddable nanoparticles based on carboxymethylated chitosan(CMCS).Commercially available CMCS was grafted with monomethoxy polyethylene glycol(mPEG)chains via an acid/CO2 responsive linker,i.e.,benzoic-imine,and then was used for the cross-linking with CaCI2.With a high CMCS concentration up to 7 mg/mL,stable nanoparticles were successfully prepared.The particle size grew slightly with increasing the molecular weight of mPEG.When the concentration of CaCI2 and the feed ratio of CMCS to mPEG increased,the particle size decreased at first and then increased after reaching a minimum size.When the particles were stimulated by CO2 or acid,benzoic.imine cleaved quickly,and mPEG fell off the nanoparticles simultaneously,and then flocculation and precipitation occurred.These sheddable nanoparticles might have potential application in the biomedical field in eluding the intelligent drug delivery system.
