Chain-growth radical polymerization of vinyl monomers is essential for producing a wide range of materials with properties tailored to specific applications.However,the inherent resistance of the polymer's C―C ba...Chain-growth radical polymerization of vinyl monomers is essential for producing a wide range of materials with properties tailored to specific applications.However,the inherent resistance of the polymer's C―C backbone to degradation raises significant concerns regarding long-term environmental persistence,which also limits their potential in biomedical applications.To address these challenges,researchers have developed strategies to either degrade preexisting vinyl polymers or incorporate cleavable units into the backbone to modify them with enhanced degradability.This review explores the various approaches aimed at achieving backbone degradability in chain-growth radical polymerization of vinyl monomers,while also highlighting future research directions for the development of application-driven degradable vinyl polymers.展开更多
The performance of hydrogel radical polymerization under ambient conditions is a major challenge because oxygen is an effective radical quencher and the steps to remove or neutralize it are time consuming and laboriou...The performance of hydrogel radical polymerization under ambient conditions is a major challenge because oxygen is an effective radical quencher and the steps to remove or neutralize it are time consuming and laborious.A self-initiating system consisting of transition metals and acetylacetone has been successfully developed.The system is capable of initiating free radical polymerization of hydrogels at room temperature under aerobic conditions,which is attributed to carbon radicals generated by the oxidation of acetylacetone.Some of these carbon radicals reduce oxygen to generate hydroxyl radicals,which together induce self-coagulation of hydrogels.The polymerization system was effective for a variety of monomer and hydrogel swelling and shrinking schemes,and the reaction remained successful when exposed to saturated oxygen.In conclusion,the results demonstrate that the present strategy is an effective approach to addressing the challenge of deoxygenation in polymer synthesis,and provides a convenient method for synthesizing multifunctional hydrogels under ambient conditions.展开更多
Photoredox-mediated reversible-deactivation radical polymerization(RDRP)is an effective approach to synthesize polymers with defined composition and architecture.Current photoinduced RDRP primarily depends on outer-sp...Photoredox-mediated reversible-deactivation radical polymerization(RDRP)is an effective approach to synthesize polymers with defined composition and architecture.Current photoinduced RDRP primarily depends on outer-sphere electron transfer or homolysis mechanisms.Herein,we describe an example of iodine-mediated RDRP facilitated by photoinduced charge transfer complex(CTC)catalysis.The approach uses cheap and easily accessible N^(-)heterocyclic nitrenium salt(NHN^(+)...I^(-))as the photoactive CTC.Upon the irradiation of visible light,NHN^(+)...I^(-)undergoes single electron transfer to generate NHN·and I·radicals.The NHN·radical activates dormant Pn-I polymers via inner-sphere single electron transfer,leading to the propagating Pn·radical for chain growth and the I^(-)anion for recovering the CTC,and the I·radical deactivates the polymerization via coupling with Pn·.展开更多
To precisely control intrachain π-electron delocalization and interchain interaction simultaneously is the prerequisite to obtain stable and efficient deep-blue light-emitting p-n polymer semiconductors for the polym...To precisely control intrachain π-electron delocalization and interchain interaction simultaneously is the prerequisite to obtain stable and efficient deep-blue light-emitting p-n polymer semiconductors for the polymer light-emitting diodes(PLEDs).Herein,we introduced the steric carbazole-fluorene nanogrid into light-emitting diphenyl sulfone-based p-n polymer semiconductors(PG and PDG) via metal-free C-N coupling polymerization for the fabrication of deep-blue PLEDs.The steric,rigid and twisted configuration between nanogrid and diphenyl sulfone in PG and PDG present the unique characteristic of large steric hindrance interaction to suppress interchain aggregation in solid state.Due to the different length of electron-deficient diphenyl sulfone monomers,PG showed a deep-blue emission with a maximum peak at 428 nm but red-shifted to 480 nm for the PDG films.Interestingly,similar deep-blue emission behavior of PG in diluted non-polar solution and films suggested the extremely weak interchain aggregation.Finally,PLEDs based on PG are fabricated with a stable deep-blue emission of CIE(0.15,0.10),and corresponding EL spectral profile is also completely identical to PL ones of diluted solution,revealed the intrachain emission without obvious interchain excited state,confirmed effectiveness of the steric hindrance functionalization of nanogrid in p-n polymer semiconductor for deep-blue light-emitting organic optoelectronics.展开更多
Heterogeneous polymerization represents a widely employed method in the polyolefin industry.In recent years,various heterogenization strategies for late transition metal catalysts have been developed,enabling effectiv...Heterogeneous polymerization represents a widely employed method in the polyolefin industry.In recent years,various heterogenization strategies for late transition metal catalysts have been developed,enabling effective control of polymer morphology and optimization of catalytic performance.However,while most studies have focused on designing anchoring groups and advancing support approaches,systematic investigations into how the support influences the catalytic behavior of the late transition metal catalysts.In this work,we fabricated supported α-diimine nickel catalysts by functionalizing the ligand with alkyl alcohol chains of varying lengths and supporting them onto MgCl_(2)supports.The ethylene polymerization behavior of these catalysts was then investigated.By precisely adjusting the alkyl alcohol chain length,the distance between the catalytically active metal center and the support surface was modulated.This approach demonstrates that support-induced steric hindrance effect can be effectively regulated by controlling the separation distance between the metal center and the support surface.展开更多
Selective depression of pyrite remains a major bottleneck in copper flotation,particularly when high-pyrite ores are processed and saline water is used.In such environments,conventional approaches using lime and inert...Selective depression of pyrite remains a major bottleneck in copper flotation,particularly when high-pyrite ores are processed and saline water is used.In such environments,conventional approaches using lime and inert grinding media often fail to discriminate ef-fectively between pyrite and valuable copper minerals due to strong copper activation on pyrite surfaces.This study introduced a novel approach using inorganic radicals generated from peroxymonosulfate(PMS)to selectively oxidize and depress pyrite.Flotation tests with synthetic high-pyrite ore blends showed that PMS significantly reduced pyrite recovery while maintaining or improving chalcopyrite flot-ation.Ethylenediaminetetraacetic acid(EDTA)extraction confirmed selective oxidation of pyrite,and electron paramagnetic resonance(EPR)spectroscopy identified hydroxyl(·OH)and sulfate(SO_(4)^(·-))radicals as the dominant reactive species.Iron ions from grinding me-dia and mineral surfaces were identified as key activators of PMS.A major insight was pyrite’s dual role,acting both as a radical scav-enger and an activator,which made it highly reactive and susceptible to radical-induced oxidation.This process converted surface copper-sulfur species into copper hydroxides,effectively suppressing pyrite flotation.While previous studies have applied EPR to detect radicals in simplified activator/precursor systems,this study provides the first direct mechanistic evidence of radical-driven selectivity in flotation by detecting inorganic radicals in a complex flotation slurry,thereby demonstrating their persistence under industrially relevant conditions and establishing a foundation for more effective and targeted flotation strategies.展开更多
Objective:To analyze the impact of nursing interventions based on quantitative assessment using the Kano model on the quality of rehabilitation in patients with early-stage ovarian cancer following laparoscopic radica...Objective:To analyze the impact of nursing interventions based on quantitative assessment using the Kano model on the quality of rehabilitation in patients with early-stage ovarian cancer following laparoscopic radical surgery.Methods:A prospective clinical study was conducted involving 96 patients with newly diagnosed early-stage ovarian cancer who underwent laparoscopic radical surgery from December 2023 to December 2025.Patients were randomly assigned to groups using a random number table method before surgery.After surgery,the control group(n=48)received routine quantitative assessment nursing interventions,while the observation group(n=48)received nursing interventions based on quantitative assessment using the Kano model.Both groups received continuous nursing care until discharge.Differences between the groups were compared in terms of negative emotions,quality of life scores before and after postoperative intervention,postoperative recovery indicators,and nursing satisfaction evaluations on the day of discharge.Results:After intervention,the observation group had lower scores on the Self-Rating Anxiety Scale(SAS)and Self-Rating Depression Scale(SDS),as well as shorter recovery times for gastrointestinal function and food intake,and a shorter hospital stay compared to the control group.Additionally,the observation group had higher scores on the Quality-of-Life Instrument for Cancer Patients-Ovarian Cancer(QLICP-OV)than the control group,with statistically significant differences(p<0.05).The overall satisfaction with nursing care in the observation group was also higher than that in the control group,with a statistically significant difference(p<0.05).Conclusion:Implementing quantitative evaluation nursing interventions based on the Kano model for patients with early-stage ovarian cancer after laparoscopic radical surgery can,by addressing their postoperative basic health,disease awareness,and other intervention content needs to a comprehensive degree,actively promote postoperative recovery and improve their mental health and quality of life.展开更多
Catalysts are key for olefin polymerization reactions and are also ubiquitous in catalysis science.Multinuclear metal catalysts have witnessed enhanced performances in catalytic reactions relative to mononuclear catal...Catalysts are key for olefin polymerization reactions and are also ubiquitous in catalysis science.Multinuclear metal catalysts have witnessed enhanced performances in catalytic reactions relative to mononuclear catalysts,but which substantially involve multi-step,tedious,and difficult synthesis.Herein,this study reports an intriguing approach to construct multi-nuclear catalysts for the milestoneα-diimine nickel catalysts using an oligomeric strategy.A polymerizable norbornene unit is incorporated into theα-diimine ligand backbone,leading to the formation of the monomeric nickel catalyst Ni_(1)and its corresponding oligomeric nickel catalysts(Ni_(3)and Ni_(5))with varying degrees of polymerization(DP=3 and 5).Notably,the oligomeric catalyst Ni_(5)was facilely scaled up(50 g-level),showed enhanced thermal stability,exhibited 4.6 times higher activity,and yielded polyethylene elastomer with a 379%increased molecular weight in ethylene polymerization,compared to the monomeric catalyst Ni_(1).Catalytic performance enhancements of oligomeric catalysts were found to be DP-dependent.The kilogram-scale polyethylene,produced using Ni_(5)in a 20 L reactor,presented a highly branched all-hydrocarbon structure,which demonstrated typical elastic properties(tensile strength:4 MPa,elastic recovery:SR=72%)along with great processability(MFI=3.0 g/10 min),insulating characteristics(volume resistivity=2×10^(16)Ω/m),and hydrophobicity(water vapor permeability:0.03 g/m^(2)/day),suggesting potentially practical applications.展开更多
Radical cycloaddition reactions(RCRs) are highly effective methods for constructing complex carbo-and heterocycles,which are frequently encountered in natural products that exhibit intriguing biological properties and...Radical cycloaddition reactions(RCRs) are highly effective methods for constructing complex carbo-and heterocycles,which are frequently encountered in natural products that exhibit intriguing biological properties and hold significant potential for applications in medicinal chemistry.Radical-mediated cycloaddition strategies,which recycle radical character,are particularly appealing because they require only a catalytic amount of reagent and promise reactions with theoretically high atom economy.This review focuses on recent developments and synthetic applications in RCRs,with an emphasis on visible lightinduced radical photocycloaddition reactions(RPCRs),transition metal-catalyzed approaches,and small molecule-catalyzed methods.By highlighting some outstanding innovations and addressing current challenges,this review aims to identify potential areas for improvement.These advancements will provide more efficient pathways for the synthesis of natural product molecules and offer valuable insights for the development of new synthetic methodologies.展开更多
Switchable polymerization is emerging as a powerful tool to construct block copolymers directly from mixtures of monomers.However,current achievements typically iterate between two polymerization cycles to afford prod...Switchable polymerization is emerging as a powerful tool to construct block copolymers directly from mixtures of monomers.However,current achievements typically iterate between two polymerization cycles to afford products with fixed sequences and compositions.Herein,we report the triethylborane/1,8-diazabicyclo[5.4.0]undec-7-ene(Et_3B/DBU)pair-mediated four-component switchable polymerization of propylene oxide(PO),CO_(2),phthalic anhydride(PA),and racemic lactide(rac-LA),which enables the on-demand synthesis of four different block copolymers,i.e.,poly(propylene phthalate)-b-polylactide(PPE-b-PLA),PPE-b-PLA-b-poly(propylene carbonate)(PPC),PPE-b-PPC-b-PLA,and PPE-b-PPCb-poly(propylene oxide)(PPO),through rationally modulating the Lewis pair(LP)ratio.Core to this protocol is that increasing the loading of Et_(3)B accelerates the ring-opening of PO while impeding the reactivity of rac-LA,thus allowing for fine-tuning of the thermodynamic and kinetic of the switchable polymerization.Therefore,the four polymerization cycles involving PO/PA ring-opening copolymerization(ROCOP),PO/CO_(2) ROCOP,rac-LA ring-opening polymerization(ROP),and PO ROP can be connected and discriminated in precisely programmed manners.展开更多
The gel polymer electrolyte containing N-propyl, methylpyrrolidinium bis（（trifiuoromethyl） sulfonyl）imide （PYR13TFSI） with better performance is prepared by radical polymerization method. The interface status be...The gel polymer electrolyte containing N-propyl, methylpyrrolidinium bis（（trifiuoromethyl） sulfonyl）imide （PYR13TFSI） with better performance is prepared by radical polymerization method. The interface status between the LiFePO4 electrode and the electrolyte is characterized by a scanning electron microscope and X-ray photoelectron spectroscopy （XPS）. There is a layer of membrane on the gel electrolyte and perfect shell membranes on the surface of active LiFePO4 cluster, on the other hand, N and S photoelectron signals are observed in XPS spectra after charge-discharge cycles. The results show that the ionic liquids and unpolymerized methyl methacrylate incorporate into the electrode surface and form the SEI membrane with Li ion and electrons while the gel electrolyte contacts with the electrode. The formation process of the SEI membrane needs at least three cycles, the discharge capacity increases as the SEI membrane becomes sufficiently thick, which blocks further electron transfer, and the system may approach steady state. The performance of cell with ionic liquid gel polymer electrolyte is measured at different rate. The cells retain 132 mAh/g at 0.2 C, 128 mAh/g at 0.5 C, and 120 mAh/g at 1.0 C after 30 cycles with charge-discharge efficiency of ca. 98% at every rate.展开更多
The branching generation during the free radical copolymerization of chain transfer monomer p-vinyl benzene sulfonyl chloride （VBSC） with styrene was investigated by a simple mathematic model. Chain transfer constan...The branching generation during the free radical copolymerization of chain transfer monomer p-vinyl benzene sulfonyl chloride （VBSC） with styrene was investigated by a simple mathematic model. Chain transfer constant of VBSC was determined to be around 0.3 by fitting the 1H-NMR monitored experimental results with a mathematic model. According to the theoretical analysis, the obtained poIy（VBSC） and its copolymers were substantiated to have a grafting-like main chain with residual pendent sulfonyl chloride groups after consuming most of the vinyl groups. The copolymerization results of VBSC with styrene at varied feed ratios demonstrated that conversion of sulfonyl chloride groups was lower than that of the monomer, which was in agreement with the theoretical results. The glass transition temperature, number average molecular weight and distribution of those obtained polymers were primarily investigated. Comparing with other chain transfer monomers, VBSC has a chain transfer constant much closer to unity therefore a more branched polymer is expected. Additionally, the branched polystyrene with residual sulfonyl chloride groups is hopefully to be further used as ATRP macro- initiators or reactive intermediates to synthesize functional polymers with complex structure.展开更多
Since tertiary amines （Cα-H） can be oxidized by peroxides and transition metal cations in high oxidation states into Ca2＋ radicals to initiate vinylic polymerizations of methacrylates, Cu2＋ and 2-（N,N-dimethylam...Since tertiary amines （Cα-H） can be oxidized by peroxides and transition metal cations in high oxidation states into Ca2＋ radicals to initiate vinylic polymerizations of methacrylates, Cu2＋ and 2-（N,N-dimethylamino）ethyl methacrylate （DMAEMA） form a polymerizable redox initiating pair, in which DMAEMA serves as an intrinsically reducing inimer. CuSOa-catalyzed aqueous self-initiated radical polymerizations of DMAEMA were successfully performed at ambient temperature via a continuous Cu2＋-tertiary amine redox initiation based on catalyst regeneration in the presence of O2. The polymerization kinetics was monitored by gas chromatography and the structure of PDMAEMA was characterized by gel- permeation chromatography, nuclear magnetic resonance spectroscopy, laser light scattering and online intrinsic-viscosity analysis. Both the monomer conversion and the molecular weight of PDMAEMA increase with the reaction while the molecular weight distribution maintains rather broad, as the Cu2＋-DMAEMA redox-initiation leads to linear PDMAEMA chains with terminal methacryloxyl moieties, and the Cu2＋-PDMAEMA redox-initiation results in branched chains. The branched topology forms and develops only for the high-MW components of the PDMAEMA. Our results provide a facile strategy to prepare branched polymers from such commercially available intrinsically reducing inimers using a negligible concentration of regenerative air-stable catalysts.展开更多
Molecular imprinting technique is a simple and efficient method for the preparation of polymer materials (i.e., molecularly imprinted polymers, MIPs) with tailor-made recognition sites for certain target molecules. Th...Molecular imprinting technique is a simple and efficient method for the preparation of polymer materials (i.e., molecularly imprinted polymers, MIPs) with tailor-made recognition sites for certain target molecules. The resulting MIPs have proven to be versatile synthetic receptors due to their high specific recognition ability, favorable mechanical, thermal and chemical stability, and ease of preparation. Recent years have witnessed significant progress in the synthesis and applications of MIPs. This review focus on the recent developments and advances in the preparation of MIPs via various controlled radical polymerization techniques.展开更多
A simple and effective method for surface molecularly imprinted composite membranes （MICMs） for artemisinin （Ars） based on regenerated cellulose membranes was first prepared through surface- initiated atom transfe...A simple and effective method for surface molecularly imprinted composite membranes （MICMs） for artemisinin （Ars） based on regenerated cellulose membranes was first prepared through surface- initiated atom transfer radical polymerization （ATRP）, and the as-prepared MICMs were then evaluated as adsorbents for selective recognition and separation of Ars molecules. Batch rebinding studies were conducted to determine the specific adsorption equilibrium, kinetics and selective permeation performance. The adsorption capacity of MICMs toward Ars by the Langmuir isotherm model was 2.008 mgg-1, which was nearly 5.0 times higher than non-molecularly imprinted composite membranes （NICMs）. The kinetic property of MICMs was well-fitted by the pseudo-second-order rate equation. The selective permeation experiments were successfully investigated to prove the excellent selective permeation performance for Ars than the competitive analog （artemether）.展开更多
Two new chiral ionic liquids, 1 -((-)-menthoxycarbonylmethylene)-3-methylimidazolium hexafluorophosphateand 1-((-)-menthoxycarbonylmethylene)-3-hexadecylimidazolium hexafluorophosphate, were designed an d prepared. Th...Two new chiral ionic liquids, 1 -((-)-menthoxycarbonylmethylene)-3-methylimidazolium hexafluorophosphateand 1-((-)-menthoxycarbonylmethylene)-3-hexadecylimidazolium hexafluorophosphate, were designed an d prepared. Theirchemical structures were characterized by ~1H-NMR. Reverse atom transfer radical polymerization of methyl methacrylate(MMA) in these two ionic liquids was carried out using AIBN/CuCl_2/bipy as the initiating system. The resultant well-definedpolymethyl methacrylate (PMMA) was employed as a macroinitiator to induce the atom transfer radical polymerization ofmenthyl methacrylate (MnMA) in chlorobenzene, which yielded a PMMA-b-PMnMA diblock copolymer with narrow polydispersity.展开更多
A general protocol was described for fabricating uniform molecularly imprinted polymer （MIP） particles via controlled living radical precipitation polymerization at ambient temperature. By adopting glutathione as mo...A general protocol was described for fabricating uniform molecularly imprinted polymer （MIP） particles via controlled living radical precipitation polymerization at ambient temperature. By adopting glutathione as model template, benzyl dithiocarbamate as iniferter agent, 4-vinylpyridine as monomer, and ethylene glycol dimethacrylate as cross-linker, it is demonstrated that the polymerization parameters including the iniferter concentration, monomer loading and molar ratio of cross-linker to functional monomer have profound effect on the final particle size and recognition property of the MIP particles. The batch static binding experiments were carried out to estimate the adsorption kinetics, adsorption isotherms and selective recognition of the MIP particles. The adsorption behavior followed the pseudo-second order kinetic model, revealing that the process was chemically carried out. Two adsorption isotherm models were applied to analyze equilibrium data, obtaining the best description by Langmuir isotherm model. In addition, the MIP particles also could selectively recognize glutathione over similar analogs, indicating the possibility for the separation and enrichment of the template from complicated matrices.展开更多
Photo-controlled reversible-deactivation radical polymerizati on(photo-RDRP)has been investigated as a"green"and spatiotem-porally controlling pathway for polymer synthesis.While the combination of photo-RDR...Photo-controlled reversible-deactivation radical polymerizati on(photo-RDRP)has been investigated as a"green"and spatiotem-porally controlling pathway for polymer synthesis.While the combination of photo-RDRP and flow chemistry has offered opportunities to increase light intensity and enable uniform light irradiation,problems associated with flow approaches still remain for photoflow-RDRP,which has hindered merging flow polymerization with other cutting-edge techniques.Herein,we summarize challenges and recent achievements in photoflow-RDRP including the development of(a)droplet/slug-flow to regulate reside nee time distribution,(b)mixing techniques to tailor polymer,(c)polymerization in duced self-assembly,and(d)computer-aided synthesis.We hope this work will provide in formative knowledge to people in related fields and stimulate novel ideas to promote polymer synthesis in both academia and industry.展开更多
The polymerization behaviors of Styrene (St) in the presence of CuX/L [X=Cl or Br; L= 2,2 bipyridine (bpy), 1,10 phenanthroline (phen) or 4,7 diphenyl 1,10 phenanthroline (DPP) ] and R X (R=trichloromethyl, benz...The polymerization behaviors of Styrene (St) in the presence of CuX/L [X=Cl or Br; L= 2,2 bipyridine (bpy), 1,10 phenanthroline (phen) or 4,7 diphenyl 1,10 phenanthroline (DPP) ] and R X (R=trichloromethyl, benzyl or allyl; X=Cl or Br) have been studied and examined. In a CuCl/bpy/RCl/St system, a bimodal GPC peak at the early stage of polymerization was observed, and a concept of multi active species was proposed to explain this phenomenon. In a CuCl/phen (DPP)/RCl/St system, the \%M\%\-n of polystyrene (PS) increased linearly with St conversion and ln[M] o/[M] also increased linearly with time, indicating the living nature of this system. Furthermore, the stability of the propagating active species in a CuBr/phen/RBr/St system is higher than that in the CuBr/phen/RBr/St system.展开更多
基金funding from the National Natural Science Foundation of China(No.22401037)funding from JST CREST(No.JPMJCR23L1)。
文摘Chain-growth radical polymerization of vinyl monomers is essential for producing a wide range of materials with properties tailored to specific applications.However,the inherent resistance of the polymer's C―C backbone to degradation raises significant concerns regarding long-term environmental persistence,which also limits their potential in biomedical applications.To address these challenges,researchers have developed strategies to either degrade preexisting vinyl polymers or incorporate cleavable units into the backbone to modify them with enhanced degradability.This review explores the various approaches aimed at achieving backbone degradability in chain-growth radical polymerization of vinyl monomers,while also highlighting future research directions for the development of application-driven degradable vinyl polymers.
基金funded by the National Key R&D Program of China(No.2022YFF0904000)Cross-disciplinary Innovation Project of Jilin University(No.JLUXKJC2021ZZ01)the financial support from National Natural Science Foundation of China(No.62201497).
文摘The performance of hydrogel radical polymerization under ambient conditions is a major challenge because oxygen is an effective radical quencher and the steps to remove or neutralize it are time consuming and laborious.A self-initiating system consisting of transition metals and acetylacetone has been successfully developed.The system is capable of initiating free radical polymerization of hydrogels at room temperature under aerobic conditions,which is attributed to carbon radicals generated by the oxidation of acetylacetone.Some of these carbon radicals reduce oxygen to generate hydroxyl radicals,which together induce self-coagulation of hydrogels.The polymerization system was effective for a variety of monomer and hydrogel swelling and shrinking schemes,and the reaction remained successful when exposed to saturated oxygen.In conclusion,the results demonstrate that the present strategy is an effective approach to addressing the challenge of deoxygenation in polymer synthesis,and provides a convenient method for synthesizing multifunctional hydrogels under ambient conditions.
基金Supported by the National Natural Science Foundation of China(Nos.21773240 and 22173103)the University of the Chinese Academy of Sciences and Beijing National Laboratory for Molecular Sciences(No.BNLMS2023014)。
文摘Photoredox-mediated reversible-deactivation radical polymerization(RDRP)is an effective approach to synthesize polymers with defined composition and architecture.Current photoinduced RDRP primarily depends on outer-sphere electron transfer or homolysis mechanisms.Herein,we describe an example of iodine-mediated RDRP facilitated by photoinduced charge transfer complex(CTC)catalysis.The approach uses cheap and easily accessible N^(-)heterocyclic nitrenium salt(NHN^(+)...I^(-))as the photoactive CTC.Upon the irradiation of visible light,NHN^(+)...I^(-)undergoes single electron transfer to generate NHN·and I·radicals.The NHN·radical activates dormant Pn-I polymers via inner-sphere single electron transfer,leading to the propagating Pn·radical for chain growth and the I^(-)anion for recovering the CTC,and the I·radical deactivates the polymerization via coupling with Pn·.
基金the support from the Jiangsu Provincial Senior Talent Program (Dengfeng,Jiangsu University)the support from the National Key R&D Program of China (No.2024YFB3612600)+3 种基金the National Natural Science Foundation of China (Nos.22275098,62288102)Basic Research Program of Jiangsu (No.BK20243057)the Natural Science Research Start-up Foundation of Recruiting Talents of Nanjing University of Posts and Telecommunications (No.NY222097)the National Natural Science Foundation of China (No.62205035)。
文摘To precisely control intrachain π-electron delocalization and interchain interaction simultaneously is the prerequisite to obtain stable and efficient deep-blue light-emitting p-n polymer semiconductors for the polymer light-emitting diodes(PLEDs).Herein,we introduced the steric carbazole-fluorene nanogrid into light-emitting diphenyl sulfone-based p-n polymer semiconductors(PG and PDG) via metal-free C-N coupling polymerization for the fabrication of deep-blue PLEDs.The steric,rigid and twisted configuration between nanogrid and diphenyl sulfone in PG and PDG present the unique characteristic of large steric hindrance interaction to suppress interchain aggregation in solid state.Due to the different length of electron-deficient diphenyl sulfone monomers,PG showed a deep-blue emission with a maximum peak at 428 nm but red-shifted to 480 nm for the PDG films.Interestingly,similar deep-blue emission behavior of PG in diluted non-polar solution and films suggested the extremely weak interchain aggregation.Finally,PLEDs based on PG are fabricated with a stable deep-blue emission of CIE(0.15,0.10),and corresponding EL spectral profile is also completely identical to PL ones of diluted solution,revealed the intrachain emission without obvious interchain excited state,confirmed effectiveness of the steric hindrance functionalization of nanogrid in p-n polymer semiconductor for deep-blue light-emitting organic optoelectronics.
基金financially supported by the National Natural Science Foundation of China(No.52473338)the National Natural Science Foundation of China(Nos.52173004 and 51873055)+3 种基金Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDA0540000)Advanced Materials-National Science and Technology Major Project(No.2025ZD0614000)Hebei Natural Science Foundation(No.E2022202015)Anhui Province Science and Technology Innovation Tackling Key Project(No.202423i08050025)。
文摘Heterogeneous polymerization represents a widely employed method in the polyolefin industry.In recent years,various heterogenization strategies for late transition metal catalysts have been developed,enabling effective control of polymer morphology and optimization of catalytic performance.However,while most studies have focused on designing anchoring groups and advancing support approaches,systematic investigations into how the support influences the catalytic behavior of the late transition metal catalysts.In this work,we fabricated supported α-diimine nickel catalysts by functionalizing the ligand with alkyl alcohol chains of varying lengths and supporting them onto MgCl_(2)supports.The ethylene polymerization behavior of these catalysts was then investigated.By precisely adjusting the alkyl alcohol chain length,the distance between the catalytically active metal center and the support surface was modulated.This approach demonstrates that support-induced steric hindrance effect can be effectively regulated by controlling the separation distance between the metal center and the support surface.
基金support from the Australian Research Council(ARC)Linkage Project(No.LP230100166).
文摘Selective depression of pyrite remains a major bottleneck in copper flotation,particularly when high-pyrite ores are processed and saline water is used.In such environments,conventional approaches using lime and inert grinding media often fail to discriminate ef-fectively between pyrite and valuable copper minerals due to strong copper activation on pyrite surfaces.This study introduced a novel approach using inorganic radicals generated from peroxymonosulfate(PMS)to selectively oxidize and depress pyrite.Flotation tests with synthetic high-pyrite ore blends showed that PMS significantly reduced pyrite recovery while maintaining or improving chalcopyrite flot-ation.Ethylenediaminetetraacetic acid(EDTA)extraction confirmed selective oxidation of pyrite,and electron paramagnetic resonance(EPR)spectroscopy identified hydroxyl(·OH)and sulfate(SO_(4)^(·-))radicals as the dominant reactive species.Iron ions from grinding me-dia and mineral surfaces were identified as key activators of PMS.A major insight was pyrite’s dual role,acting both as a radical scav-enger and an activator,which made it highly reactive and susceptible to radical-induced oxidation.This process converted surface copper-sulfur species into copper hydroxides,effectively suppressing pyrite flotation.While previous studies have applied EPR to detect radicals in simplified activator/precursor systems,this study provides the first direct mechanistic evidence of radical-driven selectivity in flotation by detecting inorganic radicals in a complex flotation slurry,thereby demonstrating their persistence under industrially relevant conditions and establishing a foundation for more effective and targeted flotation strategies.
文摘Objective:To analyze the impact of nursing interventions based on quantitative assessment using the Kano model on the quality of rehabilitation in patients with early-stage ovarian cancer following laparoscopic radical surgery.Methods:A prospective clinical study was conducted involving 96 patients with newly diagnosed early-stage ovarian cancer who underwent laparoscopic radical surgery from December 2023 to December 2025.Patients were randomly assigned to groups using a random number table method before surgery.After surgery,the control group(n=48)received routine quantitative assessment nursing interventions,while the observation group(n=48)received nursing interventions based on quantitative assessment using the Kano model.Both groups received continuous nursing care until discharge.Differences between the groups were compared in terms of negative emotions,quality of life scores before and after postoperative intervention,postoperative recovery indicators,and nursing satisfaction evaluations on the day of discharge.Results:After intervention,the observation group had lower scores on the Self-Rating Anxiety Scale(SAS)and Self-Rating Depression Scale(SDS),as well as shorter recovery times for gastrointestinal function and food intake,and a shorter hospital stay compared to the control group.Additionally,the observation group had higher scores on the Quality-of-Life Instrument for Cancer Patients-Ovarian Cancer(QLICP-OV)than the control group,with statistically significant differences(p<0.05).The overall satisfaction with nursing care in the observation group was also higher than that in the control group,with a statistically significant difference(p<0.05).Conclusion:Implementing quantitative evaluation nursing interventions based on the Kano model for patients with early-stage ovarian cancer after laparoscopic radical surgery can,by addressing their postoperative basic health,disease awareness,and other intervention content needs to a comprehensive degree,actively promote postoperative recovery and improve their mental health and quality of life.
基金financial support from the National Natural Science Foundation of China(Nos.22401274,U23B6011)the Jilin Provincial Science and Technology Department Program(No.20250102070JC)。
文摘Catalysts are key for olefin polymerization reactions and are also ubiquitous in catalysis science.Multinuclear metal catalysts have witnessed enhanced performances in catalytic reactions relative to mononuclear catalysts,but which substantially involve multi-step,tedious,and difficult synthesis.Herein,this study reports an intriguing approach to construct multi-nuclear catalysts for the milestoneα-diimine nickel catalysts using an oligomeric strategy.A polymerizable norbornene unit is incorporated into theα-diimine ligand backbone,leading to the formation of the monomeric nickel catalyst Ni_(1)and its corresponding oligomeric nickel catalysts(Ni_(3)and Ni_(5))with varying degrees of polymerization(DP=3 and 5).Notably,the oligomeric catalyst Ni_(5)was facilely scaled up(50 g-level),showed enhanced thermal stability,exhibited 4.6 times higher activity,and yielded polyethylene elastomer with a 379%increased molecular weight in ethylene polymerization,compared to the monomeric catalyst Ni_(1).Catalytic performance enhancements of oligomeric catalysts were found to be DP-dependent.The kilogram-scale polyethylene,produced using Ni_(5)in a 20 L reactor,presented a highly branched all-hydrocarbon structure,which demonstrated typical elastic properties(tensile strength:4 MPa,elastic recovery:SR=72%)along with great processability(MFI=3.0 g/10 min),insulating characteristics(volume resistivity=2×10^(16)Ω/m),and hydrophobicity(water vapor permeability:0.03 g/m^(2)/day),suggesting potentially practical applications.
基金The financial support from the National Natural Science Foundation of China (Nos.22150410339,W2432012,22301237 and 22171218)the Ministry of Science and Technology China (No.wgxz2022188) is greatly acknowledged。
文摘Radical cycloaddition reactions(RCRs) are highly effective methods for constructing complex carbo-and heterocycles,which are frequently encountered in natural products that exhibit intriguing biological properties and hold significant potential for applications in medicinal chemistry.Radical-mediated cycloaddition strategies,which recycle radical character,are particularly appealing because they require only a catalytic amount of reagent and promise reactions with theoretically high atom economy.This review focuses on recent developments and synthetic applications in RCRs,with an emphasis on visible lightinduced radical photocycloaddition reactions(RPCRs),transition metal-catalyzed approaches,and small molecule-catalyzed methods.By highlighting some outstanding innovations and addressing current challenges,this review aims to identify potential areas for improvement.These advancements will provide more efficient pathways for the synthesis of natural product molecules and offer valuable insights for the development of new synthetic methodologies.
基金financially supported by National Key R&D Program Young Scientists Project(No.2023YFC3903100)the National Natural Science Foundation of China(No.22322503)analytical and testing assistance from the Analysis and Testing Center of HUST。
文摘Switchable polymerization is emerging as a powerful tool to construct block copolymers directly from mixtures of monomers.However,current achievements typically iterate between two polymerization cycles to afford products with fixed sequences and compositions.Herein,we report the triethylborane/1,8-diazabicyclo[5.4.0]undec-7-ene(Et_3B/DBU)pair-mediated four-component switchable polymerization of propylene oxide(PO),CO_(2),phthalic anhydride(PA),and racemic lactide(rac-LA),which enables the on-demand synthesis of four different block copolymers,i.e.,poly(propylene phthalate)-b-polylactide(PPE-b-PLA),PPE-b-PLA-b-poly(propylene carbonate)(PPC),PPE-b-PPC-b-PLA,and PPE-b-PPCb-poly(propylene oxide)(PPO),through rationally modulating the Lewis pair(LP)ratio.Core to this protocol is that increasing the loading of Et_(3)B accelerates the ring-opening of PO while impeding the reactivity of rac-LA,thus allowing for fine-tuning of the thermodynamic and kinetic of the switchable polymerization.Therefore,the four polymerization cycles involving PO/PA ring-opening copolymerization(ROCOP),PO/CO_(2) ROCOP,rac-LA ring-opening polymerization(ROP),and PO ROP can be connected and discriminated in precisely programmed manners.
基金V. ACKNOWLEDGMENTS This work was supported by the Innovative Research Team of green chemical technology in University of Heilongjiang Province, the Natural Science Foundation of Heilongjiang Province of China （No.B201007 and No.E201141）, Harbin Innovation Talents of Science and Technology of Special Fund Project （No.2012RFQXG085）, and Educational Commission of Heilongjiang Province of China （No.12521z008 and No.12511443）.
文摘The gel polymer electrolyte containing N-propyl, methylpyrrolidinium bis（（trifiuoromethyl） sulfonyl）imide （PYR13TFSI） with better performance is prepared by radical polymerization method. The interface status between the LiFePO4 electrode and the electrolyte is characterized by a scanning electron microscope and X-ray photoelectron spectroscopy （XPS）. There is a layer of membrane on the gel electrolyte and perfect shell membranes on the surface of active LiFePO4 cluster, on the other hand, N and S photoelectron signals are observed in XPS spectra after charge-discharge cycles. The results show that the ionic liquids and unpolymerized methyl methacrylate incorporate into the electrode surface and form the SEI membrane with Li ion and electrons while the gel electrolyte contacts with the electrode. The formation process of the SEI membrane needs at least three cycles, the discharge capacity increases as the SEI membrane becomes sufficiently thick, which blocks further electron transfer, and the system may approach steady state. The performance of cell with ionic liquid gel polymer electrolyte is measured at different rate. The cells retain 132 mAh/g at 0.2 C, 128 mAh/g at 0.5 C, and 120 mAh/g at 1.0 C after 30 cycles with charge-discharge efficiency of ca. 98% at every rate.
基金supported by the National Natural Science Foundation of China(No.51003091)the Education Research Foundation of Yunnan Province(No.2010Y240)+1 种基金the Research Foundation of Yunnan University(No.2009B06Q)the Backbone Teacher Training Program of Yunnan University(No.21132014)
文摘The branching generation during the free radical copolymerization of chain transfer monomer p-vinyl benzene sulfonyl chloride （VBSC） with styrene was investigated by a simple mathematic model. Chain transfer constant of VBSC was determined to be around 0.3 by fitting the 1H-NMR monitored experimental results with a mathematic model. According to the theoretical analysis, the obtained poIy（VBSC） and its copolymers were substantiated to have a grafting-like main chain with residual pendent sulfonyl chloride groups after consuming most of the vinyl groups. The copolymerization results of VBSC with styrene at varied feed ratios demonstrated that conversion of sulfonyl chloride groups was lower than that of the monomer, which was in agreement with the theoretical results. The glass transition temperature, number average molecular weight and distribution of those obtained polymers were primarily investigated. Comparing with other chain transfer monomers, VBSC has a chain transfer constant much closer to unity therefore a more branched polymer is expected. Additionally, the branched polystyrene with residual sulfonyl chloride groups is hopefully to be further used as ATRP macro- initiators or reactive intermediates to synthesize functional polymers with complex structure.
基金financially supported by the National Natural Science Foundation of China(No.20674033)Natural Science Foundation of Jiangsu Province(No.BK2008142)Scientific Research Foundation for the Returned Overseas Chinese Scholars(State Education Ministry)
文摘Since tertiary amines （Cα-H） can be oxidized by peroxides and transition metal cations in high oxidation states into Ca2＋ radicals to initiate vinylic polymerizations of methacrylates, Cu2＋ and 2-（N,N-dimethylamino）ethyl methacrylate （DMAEMA） form a polymerizable redox initiating pair, in which DMAEMA serves as an intrinsically reducing inimer. CuSOa-catalyzed aqueous self-initiated radical polymerizations of DMAEMA were successfully performed at ambient temperature via a continuous Cu2＋-tertiary amine redox initiation based on catalyst regeneration in the presence of O2. The polymerization kinetics was monitored by gas chromatography and the structure of PDMAEMA was characterized by gel- permeation chromatography, nuclear magnetic resonance spectroscopy, laser light scattering and online intrinsic-viscosity analysis. Both the monomer conversion and the molecular weight of PDMAEMA increase with the reaction while the molecular weight distribution maintains rather broad, as the Cu2＋-DMAEMA redox-initiation leads to linear PDMAEMA chains with terminal methacryloxyl moieties, and the Cu2＋-PDMAEMA redox-initiation results in branched chains. The branched topology forms and develops only for the high-MW components of the PDMAEMA. Our results provide a facile strategy to prepare branched polymers from such commercially available intrinsically reducing inimers using a negligible concentration of regenerative air-stable catalysts.
基金National Natural Science Foundation of China (20744003, 20774044)Natural Science Foundation of Tianjin (06YFJMJC15100)A supporting program for New Century Excellent Talents (Ministry of Education) (NCET-07-0462).
文摘Molecular imprinting technique is a simple and efficient method for the preparation of polymer materials (i.e., molecularly imprinted polymers, MIPs) with tailor-made recognition sites for certain target molecules. The resulting MIPs have proven to be versatile synthetic receptors due to their high specific recognition ability, favorable mechanical, thermal and chemical stability, and ease of preparation. Recent years have witnessed significant progress in the synthesis and applications of MIPs. This review focus on the recent developments and advances in the preparation of MIPs via various controlled radical polymerization techniques.
基金financially supported by the National Natural Science Foundation of China(Nos.21077046,21107037,21176107,21174057,2100403,21207051)National key basic research development program(973 Program,No. 2012CBB21500)+2 种基金Ph.D.Programs Foundation of Ministry of Education of China(No.20123227120015)Natural Science Foundation of Jiangsu Province(Nos.BK2011461,SBK2011459, BK2011514)China Postdoctoral Science Foundation funded project(Nos.2012M511220,2013M530240)
文摘A simple and effective method for surface molecularly imprinted composite membranes （MICMs） for artemisinin （Ars） based on regenerated cellulose membranes was first prepared through surface- initiated atom transfer radical polymerization （ATRP）, and the as-prepared MICMs were then evaluated as adsorbents for selective recognition and separation of Ars molecules. Batch rebinding studies were conducted to determine the specific adsorption equilibrium, kinetics and selective permeation performance. The adsorption capacity of MICMs toward Ars by the Langmuir isotherm model was 2.008 mgg-1, which was nearly 5.0 times higher than non-molecularly imprinted composite membranes （NICMs）. The kinetic property of MICMs was well-fitted by the pseudo-second-order rate equation. The selective permeation experiments were successfully investigated to prove the excellent selective permeation performance for Ars than the competitive analog （artemether）.
基金This work was supported by the National Natural Science Foundation of China (Grants 20174001, 29992590-4) and the Ministry of Education of China for the teaching and research award fund for outstanding young teacher in higher education institutions.
文摘Two new chiral ionic liquids, 1 -((-)-menthoxycarbonylmethylene)-3-methylimidazolium hexafluorophosphateand 1-((-)-menthoxycarbonylmethylene)-3-hexadecylimidazolium hexafluorophosphate, were designed an d prepared. Theirchemical structures were characterized by ~1H-NMR. Reverse atom transfer radical polymerization of methyl methacrylate(MMA) in these two ionic liquids was carried out using AIBN/CuCl_2/bipy as the initiating system. The resultant well-definedpolymethyl methacrylate (PMMA) was employed as a macroinitiator to induce the atom transfer radical polymerization ofmenthyl methacrylate (MnMA) in chlorobenzene, which yielded a PMMA-b-PMnMA diblock copolymer with narrow polydispersity.
基金financially supported by the National Natural Science Foundation of China(No.21174111)Graduate Starting Seed Fund of Northwestern Polytechnical University(No.Z2013145)
文摘A general protocol was described for fabricating uniform molecularly imprinted polymer （MIP） particles via controlled living radical precipitation polymerization at ambient temperature. By adopting glutathione as model template, benzyl dithiocarbamate as iniferter agent, 4-vinylpyridine as monomer, and ethylene glycol dimethacrylate as cross-linker, it is demonstrated that the polymerization parameters including the iniferter concentration, monomer loading and molar ratio of cross-linker to functional monomer have profound effect on the final particle size and recognition property of the MIP particles. The batch static binding experiments were carried out to estimate the adsorption kinetics, adsorption isotherms and selective recognition of the MIP particles. The adsorption behavior followed the pseudo-second order kinetic model, revealing that the process was chemically carried out. Two adsorption isotherm models were applied to analyze equilibrium data, obtaining the best description by Langmuir isotherm model. In addition, the MIP particles also could selectively recognize glutathione over similar analogs, indicating the possibility for the separation and enrichment of the template from complicated matrices.
基金This work was financially supported by the National Natural Science Foundation of China(Nos.21704016 and 21971044).
文摘Photo-controlled reversible-deactivation radical polymerizati on(photo-RDRP)has been investigated as a"green"and spatiotem-porally controlling pathway for polymer synthesis.While the combination of photo-RDRP and flow chemistry has offered opportunities to increase light intensity and enable uniform light irradiation,problems associated with flow approaches still remain for photoflow-RDRP,which has hindered merging flow polymerization with other cutting-edge techniques.Herein,we summarize challenges and recent achievements in photoflow-RDRP including the development of(a)droplet/slug-flow to regulate reside nee time distribution,(b)mixing techniques to tailor polymer,(c)polymerization in duced self-assembly,and(d)computer-aided synthesis.We hope this work will provide in formative knowledge to people in related fields and stimulate novel ideas to promote polymer synthesis in both academia and industry.
文摘The polymerization behaviors of Styrene (St) in the presence of CuX/L [X=Cl or Br; L= 2,2 bipyridine (bpy), 1,10 phenanthroline (phen) or 4,7 diphenyl 1,10 phenanthroline (DPP) ] and R X (R=trichloromethyl, benzyl or allyl; X=Cl or Br) have been studied and examined. In a CuCl/bpy/RCl/St system, a bimodal GPC peak at the early stage of polymerization was observed, and a concept of multi active species was proposed to explain this phenomenon. In a CuCl/phen (DPP)/RCl/St system, the \%M\%\-n of polystyrene (PS) increased linearly with St conversion and ln[M] o/[M] also increased linearly with time, indicating the living nature of this system. Furthermore, the stability of the propagating active species in a CuBr/phen/RBr/St system is higher than that in the CuBr/phen/RBr/St system.
