Two pH-responsive amphiphilic diblock copolymers, namely polyisobutylene-block-poly[2-（N,N- dimethylamino）ethyl methaerylate] （PIB-b-PDMAEMA） and polyisobutylene-block-poly（metharylic acid） （PIB-b-PMAA）, were ...Two pH-responsive amphiphilic diblock copolymers, namely polyisobutylene-block-poly[2-（N,N- dimethylamino）ethyl methaerylate] （PIB-b-PDMAEMA） and polyisobutylene-block-poly（metharylic acid） （PIB-b-PMAA）, were synthesized via oxyanion-initiated polymerization, and their multiple self-assembly behaviors have been studied. An exo-01efin-terminated highly reactive polyisobutylene （HRPIB） was first changed to hydroxyl-terminated PIB （PIB-OH） via hydroboration-oxidation of C =C double bond in the chain end, and then reacted with KH to yield a potassium alcoholate of PIB （PIB-O-K＋）. PIB-O-K＋ was immediately used as a macroinitiator to polymerize DMAEMA monomer, resulting in a cationic diblock copolymer PIB-b-PDMAEMA. With the similar synthesis procedure, the anionic diblock copolymer PIB-b- PMAA could be prepared via a combination of oxyanion-initiated polymerization of tert-butyl methacrylate （tBMA） and subsequent hydrolysis of tert-butyl ester groups in PtBMA block. The functional PIB and block copolymers have been fully characterized by 1H-NMR, FT-IR spectroscopy, and gel permeation chromatography （GPC）. These samples allowed us to systematically investigate the effects of block composition on the pH responsivity and various self-assembled morphologies of the copolymers in THF/water mixed solvent. Transmission electron microscopy （TEM） images revealed that these diblock copolymers containing small amount of original PIB without exo-olefin-terminated group are able to self-assemble into micelles, vesicles with different particle sizes and cylindrical aggregates, depending on various factors including block copolymer composition, solvent polarity and pH value.展开更多
A benzophenone derivative photoinitiator, HBP-TDI-HQ-TDI-HBP （HTCTH）, was synthesized based on 4-hydroxy benzophenone （HBP）, toluene-2,4-diisocyanate （TDI） and hydroquinone （HQ）. HTCTH was a more effective pho...A benzophenone derivative photoinitiator, HBP-TDI-HQ-TDI-HBP （HTCTH）, was synthesized based on 4-hydroxy benzophenone （HBP）, toluene-2,4-diisocyanate （TDI） and hydroquinone （HQ）. HTCTH was a more effective photoinitiator which had longer wavelength absorption in the UV-vis absorption spectra than the low molecular counterpart benzophenone （BP）. It showed that both rate of polymerization （Rp） and final conversion （P） increased with increase of amine and HTCTH concentration in photopolymerization.展开更多
It is highly desirable for the promising sodium storage possessing high rate and long stable capability,which are mainly hindered by the unstable yet conventional solvent-derived organic-rich solid electrolyte interph...It is highly desirable for the promising sodium storage possessing high rate and long stable capability,which are mainly hindered by the unstable yet conventional solvent-derived organic-rich solid electrolyte interphases.Herein,an electrolyte solvation chemistry is elaborately manipulated to produce an enhanced anion-derived and inorganic components-dominated solid electrolyte interphases by introducing a low permittivity(4.33)bis(2,2,2-trifluoroethyl)ether diluent into the sodium bis(trifluoromethylsulfonyl)imidedimethoxyethane-based high concentration electrolyte to obtain a localized high concentration electrolyte.The bis(2,2,2-trifluoroethyl)ether breaks the balance of original cation solvation structure and tends to interact with Na^(+)-coordinated dimethoxyethane solvent rather than Na^(+)in high concentration electrolyte,leaving an enhanced Coulombic interaction between Na^(+)and(FSO_(2))_(2)N^(-),and more(FSO_(2))_(2)N^(-)can enter the Na^(+)solvation shell,forming a further increased number of Na^(+)-(FSO_(2))_(2)N^(-)-dimethoxyethane clusters(from 82.0%for high concentration electrolyte to 94.3%for localized high concentration electrolyte)at a low salt dosage.The preferential reduction of this(FSO_(2))_(2)N^(-)-enriched clusters rather than the dimethoxyethane-dominated Na^(+)solvation structure produces an enhanced anion-derived and inorganic components-dominated solid electrolyte interphases.The reversible charge storage process of Na is decoupled by operando Raman along with a shift of D and G peaks.Benefiting from the enhanced anion-derived electrode-electrolyte interface,the commercial hard carbon anode in localized high concentration electrolyte shows a well rate capability(5 A g^(−1),70 mAh g^(−1)),cycle performance and stability(85%of initial capacity after 700 cycles)in comparison to that of high concentration electrolyte(68%)and low concentration electrolyte(only 5%after 400 cycles),indicative of uniqueness and superiorities towards stable Na storage.展开更多
Ferrocenium monocations as photoinitiators for cationic photopolymerization suffer from a limitation of low absorption and low reactivity under high-pressure Hg lamp. Here, a ferrocenium dication salt, biphenyl bis [...Ferrocenium monocations as photoinitiators for cationic photopolymerization suffer from a limitation of low absorption and low reactivity under high-pressure Hg lamp. Here, a ferrocenium dication salt, biphenyl bis [π-cyclopentadienyl）iron] hexafluorophosphate （[bis（Cp-Fe）-biphenyl] （PF6）2 was synthesized by the ligand exchange reaction between ferrocene and biphenyl. The chemical structure was characterized with FTIR and ^1HNMR. The separation of ferrocenium monocation cyclopentadien-iron-biphenyl hexafluorophosphate （[Cp-Fe-biphenyl] PF6） and dication [bis（Cp-Fe）-biphenyl] （PF6）2 was carried out by column chromatography. The photoactivity of initiating photopolyinerization of epoxide ER14221 was studied as a cationic photoinitiator. [Bis（Cp-Fe）-biphenyl] （PF6）2 can efficiently absorb radiation above 300nm and its photoactivity is higher than that of its monocation.展开更多
Solid-state Li metal battery has attracted increasing interests for its potentiallyhigh energy density and excellent safety assurance, which is a promising candidatefor next generation battery system. However, the low...Solid-state Li metal battery has attracted increasing interests for its potentiallyhigh energy density and excellent safety assurance, which is a promising candidatefor next generation battery system. However, the low ionic conductivityand Li^(+) transport number of solid-state polymer electrolytes limit their practicalapplication. Herein, a composite polymer electrolyte with self-insertedstructure is proposed using the layered double hydroxides (LDHs) as dopant toachieve a fast Li^(+) transport channel in poly(vinylidene-co-trifluoroethylene) [P(VDF-TrFE)] based polymer electrolyte. In such a composite electrolyte, P(VDF-TrFE) polymer has an all-trans conformation, in which all fluorineatoms locate on one side of the polymer chain, providing fast Li^(+) transporthighways. Meanwhile, the LDH can immobilize the anions of Li salts based onthe electrostatic interactions, promoting the dissociation of Li salts, therebyenhancing the ionic conductivity (6.4 × 10^(-4) S cm^(-1)) and Li^(+) transferencenumber (0.76). The anion immobilization effect can realize uniform electricfield distribution at the anode surface and suppress the dendritic Li growth.Moreover, the hydrogen bonding interaction between LDH and polymerchains also endows the composite electrolyte with strong mechanical properties.Thus, at room temperature, the Li jj Li symmetric cells can be stablycycled over 1000 h at a current density of 0.2 mA cm^(-2), and the full cells withLiFePO_(4) cathode deliver a high capacity retention (>95%) after 200 cycles. This work offers a promising route to construct solid-state polymer electrolytes withfast Li^(+) transport.展开更多
The unscientific application of synthetic pesticides has brought various negative effects on the environment,hindering the sustainable development of agriculture.Nanoparticles can be applied as carriers to improve pes...The unscientific application of synthetic pesticides has brought various negative effects on the environment,hindering the sustainable development of agriculture.Nanoparticles can be applied as carriers to improve pesticide delivery,showing great potential in the development of pesticide formulation in recent years.Herein,a star polymer(SPc)was constructed as an efficient pesticide nanocarrier/adjuvant that could spontaneously assemble with thiocyclam or monosultap into a complex,through hydrophobic association and hydrogen bonding,respectively,with the pesticide-loading contents of 42.54%and 19.3%.This complexation reduced the particle sizes of thiocyclam from 543.54 to 52.74 nm for pure thiocyclam,and 3814.16 to 1185.89 nm for commercial preparation(cp)of thiocyclam.Interestingly,the introduction of SPc decreased the contact angles of both pure and cp thiocyclam on plant leaves,and increased the plant uptake of cp thiocyclam to 2.4–1.9 times of that without SPc.Meanwhile,the SPc could promote the bioactivity of pure/cp thiocyclam against green peach aphids through leaf dipping method and root application.For leaf dipping method,the 50%lethal concentration decreased from 0.532 to 0.221 g/L after the complexation of pure thiocyclam with SPc,and that decreased from 0.390 to 0.251 g/L for cp thiocyclam.SPc seems a promising adjuvant for nanometerization of both pure and cp insecticides,which is beneficial for improving the delivery efficiency and utilization rate of pesticides.展开更多
基金financially supported by the National Natural Science Foundation of China (Nos. 20974074 and 21074078)Natural Science Foundation of Jiangsu Province for Rolling Support Project (BK2011045)+1 种基金a project funded by the PriorityAcademic Program Development of Jiangsu Higher Education Institutions, State Key Lab of Chemical Resource Engineering(Beijing University of Chemical Technology)the Innovation Project of Graduate Students of Jiangsu Province, China(CXZZ11_0091)
文摘Two pH-responsive amphiphilic diblock copolymers, namely polyisobutylene-block-poly[2-（N,N- dimethylamino）ethyl methaerylate] （PIB-b-PDMAEMA） and polyisobutylene-block-poly（metharylic acid） （PIB-b-PMAA）, were synthesized via oxyanion-initiated polymerization, and their multiple self-assembly behaviors have been studied. An exo-01efin-terminated highly reactive polyisobutylene （HRPIB） was first changed to hydroxyl-terminated PIB （PIB-OH） via hydroboration-oxidation of C =C double bond in the chain end, and then reacted with KH to yield a potassium alcoholate of PIB （PIB-O-K＋）. PIB-O-K＋ was immediately used as a macroinitiator to polymerize DMAEMA monomer, resulting in a cationic diblock copolymer PIB-b-PDMAEMA. With the similar synthesis procedure, the anionic diblock copolymer PIB-b- PMAA could be prepared via a combination of oxyanion-initiated polymerization of tert-butyl methacrylate （tBMA） and subsequent hydrolysis of tert-butyl ester groups in PtBMA block. The functional PIB and block copolymers have been fully characterized by 1H-NMR, FT-IR spectroscopy, and gel permeation chromatography （GPC）. These samples allowed us to systematically investigate the effects of block composition on the pH responsivity and various self-assembled morphologies of the copolymers in THF/water mixed solvent. Transmission electron microscopy （TEM） images revealed that these diblock copolymers containing small amount of original PIB without exo-olefin-terminated group are able to self-assemble into micelles, vesicles with different particle sizes and cylindrical aggregates, depending on various factors including block copolymer composition, solvent polarity and pH value.
基金the National Natural Science Foundation of China(No.50473024)for its financial support.
文摘A benzophenone derivative photoinitiator, HBP-TDI-HQ-TDI-HBP （HTCTH）, was synthesized based on 4-hydroxy benzophenone （HBP）, toluene-2,4-diisocyanate （TDI） and hydroquinone （HQ）. HTCTH was a more effective photoinitiator which had longer wavelength absorption in the UV-vis absorption spectra than the low molecular counterpart benzophenone （BP）. It showed that both rate of polymerization （Rp） and final conversion （P） increased with increase of amine and HTCTH concentration in photopolymerization.
基金partly supported by the Innovation Program of Dalian City of Liaoning Province(no.2019RJ03)National Natural Science Foundation of China(NSFC,no.51872035,22078052)
文摘It is highly desirable for the promising sodium storage possessing high rate and long stable capability,which are mainly hindered by the unstable yet conventional solvent-derived organic-rich solid electrolyte interphases.Herein,an electrolyte solvation chemistry is elaborately manipulated to produce an enhanced anion-derived and inorganic components-dominated solid electrolyte interphases by introducing a low permittivity(4.33)bis(2,2,2-trifluoroethyl)ether diluent into the sodium bis(trifluoromethylsulfonyl)imidedimethoxyethane-based high concentration electrolyte to obtain a localized high concentration electrolyte.The bis(2,2,2-trifluoroethyl)ether breaks the balance of original cation solvation structure and tends to interact with Na^(+)-coordinated dimethoxyethane solvent rather than Na^(+)in high concentration electrolyte,leaving an enhanced Coulombic interaction between Na^(+)and(FSO_(2))_(2)N^(-),and more(FSO_(2))_(2)N^(-)can enter the Na^(+)solvation shell,forming a further increased number of Na^(+)-(FSO_(2))_(2)N^(-)-dimethoxyethane clusters(from 82.0%for high concentration electrolyte to 94.3%for localized high concentration electrolyte)at a low salt dosage.The preferential reduction of this(FSO_(2))_(2)N^(-)-enriched clusters rather than the dimethoxyethane-dominated Na^(+)solvation structure produces an enhanced anion-derived and inorganic components-dominated solid electrolyte interphases.The reversible charge storage process of Na is decoupled by operando Raman along with a shift of D and G peaks.Benefiting from the enhanced anion-derived electrode-electrolyte interface,the commercial hard carbon anode in localized high concentration electrolyte shows a well rate capability(5 A g^(−1),70 mAh g^(−1)),cycle performance and stability(85%of initial capacity after 700 cycles)in comparison to that of high concentration electrolyte(68%)and low concentration electrolyte(only 5%after 400 cycles),indicative of uniqueness and superiorities towards stable Na storage.
基金Supported by the National Natural Science Foundation of China （20676012）.
文摘Ferrocenium monocations as photoinitiators for cationic photopolymerization suffer from a limitation of low absorption and low reactivity under high-pressure Hg lamp. Here, a ferrocenium dication salt, biphenyl bis [π-cyclopentadienyl）iron] hexafluorophosphate （[bis（Cp-Fe）-biphenyl] （PF6）2 was synthesized by the ligand exchange reaction between ferrocene and biphenyl. The chemical structure was characterized with FTIR and ^1HNMR. The separation of ferrocenium monocation cyclopentadien-iron-biphenyl hexafluorophosphate （[Cp-Fe-biphenyl] PF6） and dication [bis（Cp-Fe）-biphenyl] （PF6）2 was carried out by column chromatography. The photoactivity of initiating photopolyinerization of epoxide ER14221 was studied as a cationic photoinitiator. [Bis（Cp-Fe）-biphenyl] （PF6）2 can efficiently absorb radiation above 300nm and its photoactivity is higher than that of its monocation.
基金National Natural Science Foundation of China,Grant/Award Number:52071227Beijing Natural Science Foundation-Xiaomi Innovation Joint Foundation,Grant/Award Number:L223011+6 种基金Key Scientific Research Project in Shanxi Province,Grant/Award Number:201805D121003Special Found Projects for Central Government Guidance to Local Science and Technology Development,Science and Technology Major Projects of Shanxi Province,Grant/Award Number:20191102004Young Elite Scientists Sponsorship Program,Grant/Award Number:CAST(2022QNRC001)Fundamental Research Program of Shanxi Province,Grant/Award Number:202103021222006Shanxi Energy Internet Research Institute,Grant/Award Number:SXEI2023A004Shanxi Scholarship Council of China,Grant/Award Number:HGKY2019085Open Research Fund of Guangdong Advanced Carbon Materials Co.,Ltd,Grant/Award Number:Kargen-2024B0905。
文摘Solid-state Li metal battery has attracted increasing interests for its potentiallyhigh energy density and excellent safety assurance, which is a promising candidatefor next generation battery system. However, the low ionic conductivityand Li^(+) transport number of solid-state polymer electrolytes limit their practicalapplication. Herein, a composite polymer electrolyte with self-insertedstructure is proposed using the layered double hydroxides (LDHs) as dopant toachieve a fast Li^(+) transport channel in poly(vinylidene-co-trifluoroethylene) [P(VDF-TrFE)] based polymer electrolyte. In such a composite electrolyte, P(VDF-TrFE) polymer has an all-trans conformation, in which all fluorineatoms locate on one side of the polymer chain, providing fast Li^(+) transporthighways. Meanwhile, the LDH can immobilize the anions of Li salts based onthe electrostatic interactions, promoting the dissociation of Li salts, therebyenhancing the ionic conductivity (6.4 × 10^(-4) S cm^(-1)) and Li^(+) transferencenumber (0.76). The anion immobilization effect can realize uniform electricfield distribution at the anode surface and suppress the dendritic Li growth.Moreover, the hydrogen bonding interaction between LDH and polymerchains also endows the composite electrolyte with strong mechanical properties.Thus, at room temperature, the Li jj Li symmetric cells can be stablycycled over 1000 h at a current density of 0.2 mA cm^(-2), and the full cells withLiFePO_(4) cathode deliver a high capacity retention (>95%) after 200 cycles. This work offers a promising route to construct solid-state polymer electrolytes withfast Li^(+) transport.
基金the Foundation of Yunnan Tobacco Company(No.2021530000241018)National Natural Science Foundation of China(No.32072497).
文摘The unscientific application of synthetic pesticides has brought various negative effects on the environment,hindering the sustainable development of agriculture.Nanoparticles can be applied as carriers to improve pesticide delivery,showing great potential in the development of pesticide formulation in recent years.Herein,a star polymer(SPc)was constructed as an efficient pesticide nanocarrier/adjuvant that could spontaneously assemble with thiocyclam or monosultap into a complex,through hydrophobic association and hydrogen bonding,respectively,with the pesticide-loading contents of 42.54%and 19.3%.This complexation reduced the particle sizes of thiocyclam from 543.54 to 52.74 nm for pure thiocyclam,and 3814.16 to 1185.89 nm for commercial preparation(cp)of thiocyclam.Interestingly,the introduction of SPc decreased the contact angles of both pure and cp thiocyclam on plant leaves,and increased the plant uptake of cp thiocyclam to 2.4–1.9 times of that without SPc.Meanwhile,the SPc could promote the bioactivity of pure/cp thiocyclam against green peach aphids through leaf dipping method and root application.For leaf dipping method,the 50%lethal concentration decreased from 0.532 to 0.221 g/L after the complexation of pure thiocyclam with SPc,and that decreased from 0.390 to 0.251 g/L for cp thiocyclam.SPc seems a promising adjuvant for nanometerization of both pure and cp insecticides,which is beneficial for improving the delivery efficiency and utilization rate of pesticides.
