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Sequence structure controllable polymerization-induced self-assembly
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作者 Zi-Xuan Chang Ren-Man Zhu +1 位作者 Chun-Yan Hong Wen-Jian Zhang 《Science China Chemistry》 SCIE EI CSCD 2024年第1期390-397,共8页
Polymerization-induced self-assembly(PISA)combines synthesis and self-assembly of artificial polymers in one-pot,which brings us one step closer to emulating biosynthesis.However,the reported PISA formulations primari... Polymerization-induced self-assembly(PISA)combines synthesis and self-assembly of artificial polymers in one-pot,which brings us one step closer to emulating biosynthesis.However,the reported PISA formulations primarily focus on developing nano-objects with new chemical compositions and rarely on structural regulation of polymers with specific components.Herein,sequence structure controllable polymerization-induced self-assembly(SCPISA)is reported by using 7-(2-methacryloyloxyethoxy)-4-methylcoumarin(CMA)as a monomer.During the copolymerization of 2-hydroxyethyl methacrylate(HEMA)and CMA,controlled incorporation of CMA units into the polymer chains can be realized by programmable light/heat changes.SCPISA-based P(HEMA-co-CMA)copolymers with the same composition but different sequence structures generate a range of assemblies.Moreover,the morphologies of the resultant nano-objects can also be controlled by regulating the feed molar ratio of CMA and HEMA,which is similar to the conventional PISA,but the synthesis procedure is obviously simplified in SCPISA.The versatility of the methodology is further demonstrated by the fabrication of different functional nano-objects with sequence structure-dependent morphologies in SCPISA systems with different functional monomers. 展开更多
关键词 polymerization-induced self-assembly sequence-controlled polymers PET-RAFT polymerization
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Self-assembly of α-6T Molecule on Ag(100) and Related STM Induced Luminescence
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作者 陈哥国 张超 +1 位作者 张瑞 董振超 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2011年第6期659-664,I0003,共7页
We have investigated the self-assembly and light emission properties of organic α- sexithiophene (α-6T) molecules on Ag(100) under different coverage by scanning tunneling microscopy (STM). At very low coverag... We have investigated the self-assembly and light emission properties of organic α- sexithiophene (α-6T) molecules on Ag(100) under different coverage by scanning tunneling microscopy (STM). At very low coverage, the α-6T molecules form a unique enantiomer by grouping four molecules into a windmill supermolecular structure. As the coverage is increased,α-6T molecules tend to pack side by side into a denser stripe structure. Further increase of the coverage will lead to the layer-by-layer growth of molecules on Ag(100) with the lower-layer stripe pattern serving as a template. Molecular fluorescence for α-6T molecules on Ag(100) at a coverage of five monolayers has been detected by light excitations, which indicates a well decoupled electronic states for the top-layer α-6T molecules. However, the STM induced luminescent spectra for the same sample reveal only plasmonic-like emission. The absence of intramolecular fluorescence in this case suggests that the electronic decoupling is not a sufficient condition for generating photon emission from molecules. For intramolecular fluorescence to occur, the orientation of the dynamic dipole moment of molecules and the energy-level alignment at the molecule-metal interface are also important so that molecules can be effectively excited through efficient dipolar coupling with local plasmons and by injecting holes into the molecules. 展开更多
关键词 α-Sexithiophene self-assembly Scanning tunneling microscopy Tunneling electron induced luminescence Surface plasmon Plasmon-exciton coupling
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Adsorption behavior of uranyl ions onto amino-type adsorbents prepared by radiation-induced graft copolymerization 被引量:3
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作者 迟洪影 刘西艳 +7 位作者 马红娟 杨晓娟 虞鸣 张建勇 王敏 李景烨 Hiroyuki Hoshina Noriaki Seko 《Nuclear Science and Techniques》 SCIE CAS CSCD 2014年第1期20-26,共7页
Amino-type adsorbents(ATAs) were prepared by radiation-induced graft copolymerization of 4-hydroxybutyl acry late glycidyl ether(HB) onto a polyethylene-coated polypropylene(PE/PP) duplex fiber of a non-woven fabric,a... Amino-type adsorbents(ATAs) were prepared by radiation-induced graft copolymerization of 4-hydroxybutyl acry late glycidyl ether(HB) onto a polyethylene-coated polypropylene(PE/PP) duplex fiber of a non-woven fabric,and modified with different amines of ethylenediamine(EDA),diethylenetriamine(DETA),triethylenetetramine(TETA) and diethylamine(DEA).The adsorption behavior of uranyl ions onto the ATAs was studied in batch experiments.The effects of the contact time,initial concentration of the ions,temperature,and pH value.The salinity were investigated along with the adsorption kinetics and the adsorption isotherms.The kinetic experimental data followed the pseudo second-order kinetic model,and the adsorption isotherms correlated well with the Langmuir model.The ATAs showed good efficiency in adsorbing uranyl ions,with the best saturation adsorption capacity being 64.26 mg g^(-1) for ATA-DETA within 120 min.The temperature dependence of ATADETA was quite abnormal and the quickest behavior was obtained at 25 ℃.ATAs showed good adsorption capacity over a wide pH range of 4.0-8.5,and HCl could be used in the elution process.Salinity of the solution had great effect on the adsorption capacity,3.5%salinity resulted in a 55%loss of capacity from ATA-DETA.The selectivity of ATA-DETA showed an order of:UO_2^(2+)≈Fe^(3+)> Zn^(2+) > VO_3^- > Co^(2+) > Ni^(2+). 展开更多
关键词 吸附行为 铀酰离子 接枝共聚 辐射诱导 吸附剂 基型 LANGMUIR模型 吸附等温线
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THE EFFECT OF POLAR ADDITIVES ON THE γ RADIATION INDUCED POLYMERIZATION OF STYRENE
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作者 张旭家 哈鸿飞 +1 位作者 吴季兰 魏根栓 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1994年第1期22-27,共6页
The γ induced polymerization of styrene in the presence of polar additives such as tributylphosphate, triethyl amine and ethanol was studied at dose rate of 5.0×10^(17) eV/ml. min. The re-sult shows that radiati... The γ induced polymerization of styrene in the presence of polar additives such as tributylphosphate, triethyl amine and ethanol was studied at dose rate of 5.0×10^(17) eV/ml. min. The re-sult shows that radiation induced polymerization of styrene was sensitized by the three kinds ofadditives at the approximate same rate and the experimental results were in agreement with thetheoretical calculation of WAS equation. The cause of sensitization is due to the proton transfer. 展开更多
关键词 STYRENE induced polymerization γ-radiolysis Ethanol polar additives
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Ultravilolet-radiation-induced graft polymerization of acrylamide onto the melt-blown polypropylene filter element by dynamic method 被引量:1
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作者 WU Lin-lin WU Guang-xia +10 位作者 XU Shu-guang ZHONG Hui SHEN Ying-jie LIU He-zhi HUANG Zheng-ming YANG Xin-bo YUAN Zong-huan TANG Lian-yi LIN Xiang-wei ZHANG Shao-lai ZHANG Wei-jun 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2007年第11期1387-1392,共6页
By dynamic method under UV irradiation, commercial melt-blown polypropylene (PPMB) filter element was modified with acrylamide (AAm) using benzophenone (BP) as initiator. Attenuated total reflection-Fourier tran... By dynamic method under UV irradiation, commercial melt-blown polypropylene (PPMB) filter element was modified with acrylamide (AAm) using benzophenone (BP) as initiator. Attenuated total reflection-Fourier transform infrared spectroscopy and scanning electron microscope verified that polyacrylamide chain was grafted on the fiber surface of PPMB filter element. Elemental content analysis with energy dispersive X-ray of fibers revealed that the polymerization content in the inner part of filter element was relatively higher than that in the outer. Degree of grafting changed with initiator concentration, monomer concentration, reaction temperature and reached 2.6% at the reaction condition: CBp=0.06 mol/L, CAAm=2.0 mol/L, irradiation time: 80 min, temperature: 60℃. Relative water flux altered with the hydrophilicity and pore size of filter element. In the antifouling test, the modified filter gave greater flux recovery (approximately 70%) after filtration of the water extract of Liuweidihuang, suggesting that the fouling layer was more easily reversible due to the hydrophilic nature of the modified filter. 展开更多
关键词 melt-blown polypropylene filter element UV-induced graft polymerization surface modification dynamic method
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Adsorbent for Arsenic(V) Removal Synthesized by Radiation-Induced Graft Polymerization onto Nonwoven Cotton Fabric 被引量:1
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作者 Hiroyuki Hoshina Makikatsu Takahashi +1 位作者 Noboru Kasai Noriaki Seko 《International Journal of Organic Chemistry》 2012年第3期173-177,共5页
A fibrous adsorbent for arsenic (As) removal was synthesized with nonwoven cotton fabric as a trunk polymer. 2-hydroxyethyl methacrylate phosphoric acid monomer which composed of phosphoric acid mono (50%) and di (50%... A fibrous adsorbent for arsenic (As) removal was synthesized with nonwoven cotton fabric as a trunk polymer. 2-hydroxyethyl methacrylate phosphoric acid monomer which composed of phosphoric acid mono (50%) and di (50%) ethyl methacrylate ester was introduced with radiation-induced graft polymerization onto nonwoven cotton fabric. The degree of grafting of 130% was obtained at irradiation dose of 20 kGy with 5% of monomer solution for 2 hours reaction time at 40?C reaction temperature. After the grafted material was contacted with 10 mmol/L of zirconium (Zr) solution at pH 1, 0.38 mmol/g of Zr was loaded on phosphoric units as a functional group for As(V) removal. The resulting adsorbent was evaluated by column mode adsorption with 1 mg/L of As(V) solution at various pH with space velocity 200 h–1. The maximum capacity of As(V) adsorption was 0.1 mmol/g at pH 2. 展开更多
关键词 ARSENIC REMOVAL Cotton RADIATION-induced Graft polymerization Phosphoric Acid Zirconium
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ELECTRON BEAM IRRADIATION INDUCED GRAFT POLYMERIZATION OF POLYETHYLENE POWDER
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作者 Yong WANG Rui Hai LI Gui Heng WANG (Department of polym. Mater., Chengdu University of Sci. and Techn., Chengdu 610065) 《Chinese Chemical Letters》 SCIE CAS CSCD 1994年第4期329-330,共2页
The graft polymerization of maleic anhydride (MA) onto preirradiated HDPE powder was studied. FTIR showed the existence of HDPE-graft-MA. The irradiation atmosphere and preirradiation dose have effects on the Percent ... The graft polymerization of maleic anhydride (MA) onto preirradiated HDPE powder was studied. FTIR showed the existence of HDPE-graft-MA. The irradiation atmosphere and preirradiation dose have effects on the Percent graft. A high degree of graft (10% ) was achieved using this process. 展开更多
关键词 BEAM ELECTRON GRAFT induced IRRADIATION OF POLYETHYLENE polymerization POWDER
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Self-assembly of Gradient Copolymer Synthesized by Spontaneous Batch RAFT Emulsion Polymerization and Its Application on Encapsulating Ag Nanoparticles
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作者 秦超然 FENG Menran +4 位作者 LUO Wen LIU Mingyang HAN Mei MA Shuai 王艺峰 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2018年第4期987-994,共8页
The gradient copolymers of acrylic acid and trifluoroethyl methacrylate(coded as P(TFEMAgrad-AA)) were synthesized via reversible addition-fragmentation transfer(RAFT) emulsifier-free emulsion polymerization. Th... The gradient copolymers of acrylic acid and trifluoroethyl methacrylate(coded as P(TFEMAgrad-AA)) were synthesized via reversible addition-fragmentation transfer(RAFT) emulsifier-free emulsion polymerization. The spontaneous batch feeding approach was used to control the gradient chain sequence. Transmission electron microscopy(TEM) analysis revealed that the P(TFEMA-grad-AA) can self-assemble to form spherical micelles, rodlike micelles or vesicles in selective solvents. Morphological transition of the P(TFEMA-grad-AA) micelles was sensitive to the water content of the dioxane/water mixed solvent. More interestingly, Ag nanoparticles(NPs) were encapsulated by the P(TFEMA-grad-AA) micelles during the selfassembly process. The gradient chain sequence made the Ag NPs easily enter the core of the micelles, even when P(TFEMA-grad-AA) had less hydrophobic fluoro-units and more hydrophilic units. TEM images with energy dispersive spectrometer indicated that the nanocomposite micelles consisted of a Ag NPs core and a gradient copolymer shell. 展开更多
关键词 gradient copolymer self-assembly ENCAPSULATION RAFT emulsion polymerization spontaneous batch feeding
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Rapid Biodiesel Fuel Production Using Novel Fibrous Catalyst Synthesized by Radiation-Induced Graft Polymerization
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作者 Yuji Ueki Nor Hasimah Mohamed +1 位作者 Noriaki Seko Masao Tamada 《International Journal of Organic Chemistry》 2011年第2期20-25,共6页
An efficient fibrous catalyst for the biodiesel fuel production has been synthesized by radiation-induced graft polymerization of 4-chloromethylstyrene onto a nonwoven polyethylene (NWPE) fabric followed by amination ... An efficient fibrous catalyst for the biodiesel fuel production has been synthesized by radiation-induced graft polymerization of 4-chloromethylstyrene onto a nonwoven polyethylene (NWPE) fabric followed by amination with trimethylamine (TMA) and further treatment with NaOH. The degree of grafting of NWPE fabric and TMA group density of fibrous catalyst could easily and reproducibly be controlled within a range of up to 340% and 3.6 mmol-TMA/g-catalyst, respectively. In the transesterification of triglycerides and ethanol using the synthesized fibrous catalyst, the conversion ratio of triglycerides reached 95% after 4 h reaction at 50°C. 展开更多
关键词 Biomass BIODIESEL Fuel TRIGLYCERIDES Heterogeneous Catalysis RADIATION-induced GRAFT polymerization RENEWABLE Resources
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Self-assembly and UV-curing Property of Polymerized Lyotropic Liquid Crystal Monomer of Sodium 3,4,5-tris(ll-acryloxyundecyloxy)benzoate 被引量:1
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作者 白玉勤 郭金宝 +1 位作者 王影 魏杰 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2013年第1期95-101,I0004,共8页
A polymerized lyotropic liquid crystal monomer of sodium 3,4,5-tris(11-acryloxyundecyloxy)- benzoate was synthesized by a convenient route starting from 3,4,5-trihydroxybenzoic acid via esterification followed by et... A polymerized lyotropic liquid crystal monomer of sodium 3,4,5-tris(11-acryloxyundecyloxy)- benzoate was synthesized by a convenient route starting from 3,4,5-trihydroxybenzoic acid via esterification followed by etherification, acylation and finally neutralization. The chemi- cal structure was confirmed by Fourier transform infrared (FT-IR) and 1H nuclear magnetic resonance spectral analysis. The self-organization behavior of the monomer with deionized water in methanol at room temperature was also demonstrated. The assemblies were char- acterized by polarized optical microscope and X-ray diffraction. The results show that a solution containing 80:20 of the monomer to water was found to be able to self-organize into Lamellar (La) phase and 92:8 with inverted hexagonal (H]I) phase, which was in ac- cordance with the theoretical calculation of critical packing parameter. It suggests that the concentration of the monomer was the key factor to influence assembly structure. Addi- tionally, the acrylate conversion with different photoinitiators and nanostructure retention after polymerization were investigated. The research shows that the acrylate conversion of the monomer with Darocur2959 could reach up to 78% when irradiated by 30 mW/cm2 UV light of 365 nm for 30 min characterized by Real-time FT-IR as well as the sol-gel method. Meanwhile, the La and HII phase nanostructures were both retained after polymerization. 展开更多
关键词 polymerized lyotropic liquid crystal self-assembly La phase HII phase UV-CURING
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Tunneling Electron Induced Fluorescence from Single Porphyrin Molecules Decoupled by Striped-Phase Octanethiol Self-assembled Monolayer
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作者 邝艳敏 郁杰 +4 位作者 骆阳 朱嘉哲 廖源 张杨 董振超 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2016年第2期157-160,I0001,共5页
We investigate tunneling electron induced luminescence from isolated single porphyrin molecules that are decoupled by striped-phase self-assembled monolayer of octanethiol from the underneath Au(111) substrate. Intr... We investigate tunneling electron induced luminescence from isolated single porphyrin molecules that are decoupled by striped-phase self-assembled monolayer of octanethiol from the underneath Au(111) substrate. Intrinsic single-molecule electroluminescence has been realized by such decoupling at both bias polarities. The photon emission intensity acquired from the molecular lobe is found stronger than that from the molecular center. These re- sults provide useful information on the understanding of electroluminescent behavior and mechanism in molecular tunnel junctions. 展开更多
关键词 Scanning tunneling microscope induced luminescence PLASMONICS PORPHYRIN Octanethiol self-assembled monolayer Striped-phase
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Self-assembly synthesis of solid polymer electrolyte with carbonate terminated poly (ethylene glycol) matrix and its application for solid state lithium battery 被引量:1
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作者 Bing Yuan Guangmei Luo +3 位作者 Jing Liang Fangyi Cheng Wangqing Zhang Jun Chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2019年第11期55-59,共5页
A facile one-pot synthesis of solid polymer electrolytes(SPEs), composed of carbonate terminated poly(ethylene glycol)(CH3O-PEG-IC), poly(ethylene glycol)-block-polystyrene(PEG-b-PS) block copolymer nanoparticles cont... A facile one-pot synthesis of solid polymer electrolytes(SPEs), composed of carbonate terminated poly(ethylene glycol)(CH3O-PEG-IC), poly(ethylene glycol)-block-polystyrene(PEG-b-PS) block copolymer nanoparticles containing a conductive PEG corona, fumed SiO2 and Li TFSI salt via polymerization-induced self-assembly is proposed. This method to prepare SPEs has the advantages of one-pot convenient synthesis, avoiding use of organic solvent and conveniently adding inorganic additives. CH3O-PEG-IC combines advantages of PEG and polycarbonate, the in situ synthesized PEG-b-PS nanoparticles containing a rigid polystyrene(PS) core and a PEG corona guarantee continuous lithium ion transport in the synthesized SPEs, and the fumed SiO2 optimizes the interfacial properties and improves the electrochemical stability, all of which afford SPEs a well considerable room temperature ionic conductivity of 1.73 × 10^-4S/cm, high lithium transference number of 0.53, and wide electrochemical stability window of 5.5 V(vs. Li^+/Li). By employing these SPEs, the assembled solid state cells of Li FePO4 |SPEs|Li exhibit considerable cell performance. 展开更多
关键词 Solid polymer ELECTROLYTE polymerization-induced self-assembly SOLID-STATE lithium battery
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Aqueous Self-Assembly of Block Copolymers to Form Manganese Oxide-Based Polymeric Vesicles for Tumor Microenvironment-Activated Drug Delivery 被引量:2
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作者 Yalei Miao Yudian Qiu +6 位作者 Mengna Zhang Ke Yan Panke Zhang Siyu Lu Zhongyi Liu Xiaojing Shi Xubo Zhao 《Nano-Micro Letters》 SCIE EI CAS CSCD 2020年第9期324-338,共15页
Molecular self-assembly is crucially fundamental to nature.However,the aqueous self-assembly of polymers is still a challenge.To achieve self-assembly of block copolymers [(polyacrylic acid-block-polyethylene glycol-b... Molecular self-assembly is crucially fundamental to nature.However,the aqueous self-assembly of polymers is still a challenge.To achieve self-assembly of block copolymers [(polyacrylic acid-block-polyethylene glycol-block-polyacrylic acid(PAA68-b-PEG86-b-PAA68)] in an aqueous phase,manganese oxide(MnO2) is first generated to drive phase separation of the PAA block to form the PAA68-b-PEG68-b-PAA68/MnO2 polymeric assembly that exhibits a stable structure in a physiological medium.The polymeric assembly exhibits vesicular morphology with a diameter of approximately 30 nm and high doxorubicin(DOX) loading capacity of approximately 94%.The transformation from MnO2 to Mn2+caused by endogenous glutathione(GSH)facilitates the disassembly of PAA68-b-PEG68-b-PAA68/MnO2 to enable its drug delivery at the tumor sites.The toxicity of DOXloaded PAA68-b-PEG68-b-PAA69/MnO2 to tumor cells has been verified in vitro and in vivo.Notably,drug-loaded polymeric vesicles have been demonstrated,especially in in vivo studies,to overcome the cardiotoxicity of DOX.We expect this work to encourage the potential application of polymer self-assembly. 展开更多
关键词 polymer Aqueous self-assembly Vesicles Tumor microenvironment Drug delivery system
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Electron density measurement of laser-induced epoxy fiber reinforced polymer plasma 被引量:1
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《强激光与粒子束》 EI CAS CSCD 北大核心 2016年第7期54-59,共6页
Interferograms of laser-induced epoxy fiber reinforced polymer plasmas are obtained through aMach-Zehnder interferometry system. An improved digital double-exposure Fourier method is applied to extractinitial wrapped ... Interferograms of laser-induced epoxy fiber reinforced polymer plasmas are obtained through aMach-Zehnder interferometry system. An improved digital double-exposure Fourier method is applied to extractinitial wrapped phases from interferograms, and then an improved phase unwrapping algorithm based on a maskand a branch-cut method is proposed to solve the problem of phase unwrapping. After the inverse Abel transfor-mation of the unwrapped phase, spatial distributions of the electron density of laser-induced epoxy fiber rein-forced polymer plasma at various delays are acquired. Results show that the measured electron density of theplasma is mainly distributed on the order of 10^18 cm^3. The experiment also indicates that the total amount oflaser plasma electrons changes slightly within the recorded time and the change of the electron density is approx-imately inversely proportional to the change of the plasma volume. 展开更多
关键词 ELECTRON DENSITY laser induced PLASMA EPOXY fiber REINFORCED polymer phase of inter-ferogram
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Thermoreversible Thickening and Self-assembly Behaviors of pH/Temperature Dually Responsive Microgels with Interpenetrating Polymer Network Structure 被引量:1
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作者 刘晓云 杨军 +1 位作者 闫伟霞 査刘生 《Journal of Donghua University(English Edition)》 EI CAS 2014年第3期312-315,共4页
The pH /temperature dually responsive microgels of interpenetrating polymer network( IPN) structure composed of poly( N-isopropylacrylamide)( PNIPAM) network and poly( acrylic acid)( PAA) network( PNIPAM /PAA IPN micr... The pH /temperature dually responsive microgels of interpenetrating polymer network( IPN) structure composed of poly( N-isopropylacrylamide)( PNIPAM) network and poly( acrylic acid)( PAA) network( PNIPAM /PAA IPN microgels) were synthesized by seed emulsion polymerization. The results obtained by dynamic laser light scattering( DLLS) show that the microgels have good pH /temperature dual sensitivities. The temperature sensitive component and the pH sensitive component inside the microgels have little interference with each other. The rheological properties of the concentrated PNIPAM /PAA IPN microgel dispersions as a function of temperature at pH 4. 0 or 7. 0 were investigated by viscometer,and the results displayed that only at pH 7. 0 the dispersions presented thermoreversible thickening behavior. Then the PNIPAM /PAA fibers were prepared by self-assembly of the PNIPAM /PAA IPN microgels in the ice-crystal templates formed by unidirectional liquid nitrogen freezing method. Field emission scanning electron microscopy( FESEM) images indicate that the PNIPAM /PAA fibers are rounded,randomly orientated and interweaved. 展开更多
关键词 interpenetrating polymer network(IPN) structure pH and temperature sensitivity thermo-thickening self-assembly
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Identification of origin of insulating polymer maneuvered photoredox catalysis
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作者 Qiao-Ling Mo Rui Xiong +5 位作者 Jun-Hao Dong Bai-Sheng Sa Jing-Ying Zheng Qing Chen Yue Wu Fang-Xing Xiao 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第8期109-123,共15页
Solid non-conjugated polymers have long been regarded as insulators due to deficiency of delocalizedπelectrons along the molecular chain framework.Up to date,origin of insulating polymer regulated charge transfer has... Solid non-conjugated polymers have long been regarded as insulators due to deficiency of delocalizedπelectrons along the molecular chain framework.Up to date,origin of insulating polymer regulated charge transfer has not yet been uncovered.In this work,we unleash the root origin of charge transport capability of insulating polymer in photocatalysis.We ascertain that insulating polymer plays crucial roles in fine tuning of electronic structure of transition metal chalcogenides(TMCs),which mainly include altering surface electron density of TMCs for accelerating charge transport kinetics,triggering the generation of defect over TMCs for prolonging carrier lifetime,and acting as hole-trapping mediator for retarding charge recombination.These synergistic roles contribute to the charge transfer of insulating polymer.Our work opens a new vista of utilizing solid insulating polymers for maneuvering charge transfer toward solar energy conversion. 展开更多
关键词 Insulating polymer Charge transfer Photoredox catalysis POLYELECTROLYTE self-assembly
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Intelligent responsive self-assembled micro-nanocapsules:Used to delay gel gelation time
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作者 Chuan-Hong Kang Ji-Xiang Guo +1 位作者 Dong-Tao Fei Wyclif Kiyingi 《Petroleum Science》 SCIE EI CAS CSCD 2024年第4期2433-2443,共11页
In the application of polymer gels to profile control and water shutoff,the gelation time will directly determine whether the gel can"go further"in the formation,but the most of the methods for delaying gel ... In the application of polymer gels to profile control and water shutoff,the gelation time will directly determine whether the gel can"go further"in the formation,but the most of the methods for delaying gel gelation time are complicated or have low responsiveness.There is an urgent need for an effective method for delaying gel gelation time with intelligent response.Inspired by the slow-release effect of drug capsules,this paper uses the self-assembly effect of gas-phase hydrophobic SiO_(2) in aqueous solution as a capsule to prepare an intelligent responsive self-assembled micro-nanocapsules.The capsule slowly releases the cross-linking agent under the stimulation of external conditions such as temperature and pH value,thus delaying gel gelation time.When the pH value is 2 and the concentration of gas-phase hydrophobic SiO_(2) particles is 10%,the gelation time of the capsule gel system at 30,60,90,and 120℃is12.5,13.2,15.2,and 21.1 times longer than that of the gel system without containing capsule,respectively.Compared with other methods,the yield stress of the gel without containing capsules was 78 Pa,and the yield stress after the addition of capsules was 322 Pa.The intelligent responsive self-assembled micronanocapsules prepared by gas-phase hydrophobic silica nanoparticles can not only delay the gel gelation time,but also increase the gel strength.The slow release of cross-linking agent from capsule provides an effective method for prolongating the gelation time of polymer gels. 展开更多
关键词 Profile control and water shutoff polymer gel Delayed gelation time Intelligent response self-assemblED Micro-nanocapsules
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Electropolymerization of 4-Aminothiophenol Self-AssembledMonolayer on Au Electrode
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作者 Qing Ji XIE Xiao Lan GU +2 位作者 You Yu ZHANG Man Cai XU Ming MA(Chemistry Department, Hunan Normal University, Changsha 410081)(Center of Analysis & Test. Hunan Normal University. Changsha 410081) 《Chinese Chemical Letters》 SCIE CAS CSCD 1999年第1期63-66,共4页
In this letter. we report that oxidation of 4-aminothiophenol self-assembled monolayeron An electrode produces a couple of redox current peaks with close peak potentials in 0.5 mol/LHCIO4 aqueous solution, and the pea... In this letter. we report that oxidation of 4-aminothiophenol self-assembled monolayeron An electrode produces a couple of redox current peaks with close peak potentials in 0.5 mol/LHCIO4 aqueous solution, and the peaks are ascribed to an electroactive monolayer.Electrochemical properties of the monolayer polymer were investigated with use ofelectrochemical quartz crystal microbalance and cyclic voltammetry. 展开更多
关键词 Molecular self-assembly monolayer polymer 4-AMINOTHIOPHENOL EQCM
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SELF-ASSEMBLY OF ROD-COIL DIBLOCK COPOLYMERS——INFLUENCE OF THE ROD LENGTH
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作者 周其凤 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2003年第5期569-573,共5页
The self-assembly of five narrowly distributed novel rod-coil diblock copolymers, poly(styrene-block-(2, 5-bis[4-methoxy-phenyl]oxycarbonyl) styrene) (PS-b-PMPCS), in p-xylene, a selective solvent at room temperature,... The self-assembly of five narrowly distributed novel rod-coil diblock copolymers, poly(styrene-block-(2, 5-bis[4-methoxy-phenyl]oxycarbonyl) styrene) (PS-b-PMPCS), in p-xylene, a selective solvent at room temperature, was studied. Therod-coil copolymers, which have the same PS length but different PMPCS length, were synthesized by 2,2,6,6-tetramethyl-I-piperidinyloxy (TEMPO) mediated living free radical polymerization. The influence of the rod length on the self-assemblymorphology was studied by transmission electron microscopy (TEM). At a concentration of 2.0 mg/mL, those copolymerswith relatively shorter PMPCS length (copolymers 1 and 2) form individual spherical micelles; those with relatively longerPMPCS length (copolymer 3 and 4) form 'pearl chains' coexisting with individual spherical micelles; the ones with longestPMPCS length form 'pearl chains' coexisting with occasionally formed nanofibers. The diameter of all the morphologieswas controlled by the rod length. This gives us a way to govern the self-assembly morphology by altering the length of oneblock in the block copolymer. 展开更多
关键词 self-assembly Rod-coil copolymer Living free radical polymerization
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Thermosensitive Polymer Nanocontainers Prepared by Self-Assembly of Block Copolymers
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作者 Chen Xiangrong Ding Xiaobing Zheng Zhaohui Peng Yuxing 《合成化学》 CAS CSCD 2004年第z1期93-93,共1页
关键词 PNIPAM PHEMA Thermosensitive polymer Nanocontainers Prepared by self-assembly of Block Copolymers
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