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SYNTHESIS OF MESOPOROUS POLY(STYRENE-co-MALEIC ANHYDRIDE)/SILICA HYBRID MATERIALS VIA A NONSURFACTANT-TEMPLATED SOL-GEL PROCESS

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Chinese Journal of polymer science 2000年第5期18卷 469-472页

作者： Jie-bin Pang Kun-yuan Qiu yen wei department of polymer science and engineering, college of chemistry and molecular engineering, peking university, beijing 100871, {13.. department of chemistry, drexel university, philadelphia, pennsylvania 19104, usa. peking Univ Coll Chem & Mol Engn Dept Polymer Sci & Engn Beijing 100871 Peoples R China drexel Univ Dept Chem Philadelphia PA 19104 USA

Mesoporous poly(styrene-co-maleic anhydride)/silica hybrid materials have been prepared. The synthesis was achieved by the HCl-catalyzed sol-gel reactions of tetraethyl orthosilicate (TEOS) and styrene-maleic anhydride copolymer in the presence of 3-aminopropyl triethoxysilane (APTES) as a coupling agent and citric acid as a nonsurfactant template or pore-forming agent, followed by ethanol extraction. Characterization results from nitrogen sorption isotherms and powder X-ray diffraction indicate that polymer-modified mesoporous materials with large specific surface areas (e.g. 900 m(2)/g) and pore volumes (e.g. 0.6 cm(3)/g) could be prepared. As the citric acid concentration is increased, the specific surface areas, pore volumes and pore diameters of the hybrid materials increase.

关键词： mesoporous hybrid material poly(styrene-co-maleic anhydride)/silica citric acid nonsurfactant template sol-gel process

TARTARIC ACID TEMPLATED SYNTHESIS OF MESOPOROUS Ti-INCORPORATED SILICA AND ITS CATALYTIC ACTIVITY FOR THE RING-OPENING polymerIZATION OF ε-CAPROLACTONE

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Chinese Journal of polymer science 2002年第4期20卷 361-368页

作者： Jie-bin Pang Chang-ming Dong Kun-yuan Qiu yen wei department of polymer science and engineering college of chemistry and molecular engineering peking university beijing 100871,{13., pennsylvania 19104, usa peking Univ Coll Chem & Mol Engn Dept Polymer Sci & Engn Beijing 100871 Peoples R China drexel Univ Dept Chem Philadelphia PA 19104 USA

Ti-incorporated mesoporous silica materials with pore diameters of 3-4 nm have been prepared via the co-hydrolysis and co-condensation reactions, that is the sol-gel reactions, of titanium (IV) tetrabutoxide and tetraethylorthosilicate in the presence of tartaric acid as template, followed by extraction with ethanol to remove the templatemolecules. The materials were characterized in detail by Fourier transform infrared spectroscopy, nitrogen adsorption-desorption test, powder X-ray diffraction, transmission electron microscopy and X-ray energy dispersive spectroscopy. Theresults indicate that the Ti-containing silica materials have large specific surface areas (ca. 1200 m^2 g^(-1)) and pore volumes(ca. 0.900 cm^3 g^(-1)). The mesoporosity arises from disordered interconnecting channels or pores. The Ti-incorporated silicasexhibit catalytic activity for the ring-opening polymerization of ε-caprolactone, otherwise, the pure mesoporous silicamaterial shows no catalytic activity under the identical conditions.

关键词： Mesoporous material Ti-incorporated silica ε-Caprolactone Ring-opening polymerization Sol-gel reactions

SYNTHESIS OF HYBRID MESOPOROUS POLYSTYRENE-SILICA MATERIALS WITH NON-SURFACTANT CITRIC ACID AS TEMPLATE VIA SOL-GEL PROCESS

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Chinese Journal of polymer science 2002年第6期20卷 565-572页

作者： Jie Bai Jin-yu Zheng Kun-yuan Qiu yen wei department of polymer science & engineering college of chemistry & molecular engineering, peking university beijing 100871, {13. department of chemistry, drexel university, philadelphia, PA 19104, usa peking Univ Coll Chem & Mol Engn Dept Polymer Sci & Engn Beijing 100871 Peoples R China drexel Univ Dept Chem Philadelphia PA 19104 USA

Hybrid mesoporous polystyrene-silica materials were successfully prepared through HCl-catalyzed sol-gel reactions of tetraethyl orthosilicate (TEOS) and triethoxysilyl-functionalized polystyrene obtained via atom transfer radical polymerization (ATRP) of styrene, in the presence of citric acid (CA) as non-surfactant template or pore-forming agent and followed by ethanol extraction to remove template molecules. The materials were characterized by infrared spectroscopy OR), N-2 adsorption-desorption measurements, powder X-ray diffraction (XRD), thermogravimetric analysis (TGA) and transmission electron microscopy (TEM). The results indicate that the materials prepared with 50 wt%-60 wt% template contents have average pore sizes of 2-3 nm and large surface areas (ca. 886 m(2)/g) as well as high pore volumes (ca. 0.53 cm(3)/g). The mesoporosity arises from interconnected channels and pores with disordered arrangements. The pore diameters and pore volumes increase as the template content is increased. The pore diameters show a little change upon heating at 200degreesC overnight. However, the materials do not have good hydrothermal stability.

关键词： atom transfer radical polymerization hybrid material mesoporous polystyrene silica

SYNTHESIS AND CHARACTERIZATION OF STRUCTURALLY WELL-DEFINED polymer-INORGANIC HYBRID NANOPARTICLES VIA ATRP

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Chinese Journal of polymer science 2002年第3期20卷 261-267页

作者： Jie Bai Jie-bin Pang Kun-yuan Qiu yen wei department of polymer science & engineering college of chemistry & molecular engineering peking university beijing 100871,{13., PA 19104 usa peking Univ Coll Chem & Mol Engn Dept Polymer Sci & Engn Beijing 100871 Peoples R China drexel Univ Dept Chem Philadelphia PA 19104 USA

Atom transfer radical polymerization (ATRP) using cuprous chloride/2,2'-bipyridine (bipy) was applied to graft polymerization of styrene on the surface of silica nanoparticles to synthesize polymer-inorganic hybrid nanoparticles, 2-(4Chloromethylphenyl) ethyltriethoxysilane (CTES) was immobilized on the surface of silica nanoparticles through condensation reaction of the silanol groups on silica with triethoxysilane group of CTES. Then ATRP of St was initiated by this surface-modified silica nanoparticles bearing benzyl chloride groups, and formed PSt graft chains on the surface of silica nanoparticles. The thickness of the graft chains increased with reaction time. End group analysis confirmed the occurrence of ATRP. Thermal analysis indicated that thermal stabilization of these resulting hybrid nanoparticles also increases with polymerization conversion. The results above show that this 'grafting from' reaction could be used for the preparation of polymer-inorganic hybrid nanoparticles with controlled structure of the polymer's end groups.

关键词： atom transfer radical polymerization polymer-inorganic hybrid nanoparticles 2-(4-chloromethylphenyl)ethyltriethoxysilane surface-modification

Measurement of Monomer Reactivity Ratios of D,L-3-Methylglycolide with Glycolide or D,L-Lactide

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Chinese Chemical Letters 2000年第9期11卷 815-818页

作者： Chang Ming DONG Kun Yuan QIU Zhong wei GU Xin De FENG department of polymer science and engineering, college of chemistry and molecular engineering, peking university, beijing 100871 National Research Institute for Family Planning, beijing 100081 peking Univ Coll Chem & Mol Engn Dept Polymer Sci & Engn Beijing 100871 Peoples R China Natl Res Inst Family Plannning Beijing 100081 Peoples R China

For monomer reactivity ratios study, the copolymerization of D,L-3-methylglycolide (MG) with glycolide (GA) or D,L-lactide (LA) was carried out in bulk to a certain low conversion in the presence of stannous octoate at 140 degrees C. The copolymer compositions were determined by H-1 NMR spectroscopy. The monomer reactivity ratios were evaluated by Fineman-Ross method, Kelen-Tudos method and linear least-squares method. The monomer reactivity ratios of D,L-3-methylglycolide and glycolide or D,L-lactide are r(mg)= 0.73, r(ga)= 1.47; r(mg)= 1.71, r(la)= 0.92, respectively.

关键词： D,L-3-methylglycolide glycolide D,L-lactide ring-opening copolymerization monomer reactivity ratios

FLUORESCENCE AND ELECTROCHEMICAL BEHAVIOR OF DANSYL-SHELLED PAMAM DENDRIMERS:EFFECT OF DENDRITIC ARCHITECTURE

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FLUORESCENCE AND ELECTROCHEMICAL BEHAVIOR OF DANSYL-SHELLED ...

Polaron interfacial entropy as a route to high thermoelectric performance in DAE-doped PEDOT:PSS films

Third East Asian polymer Conference

作者： Bing-bing Wang. Xin Zhang, Xin-ru Jia, Ling Yang, Yan Ji polymer science, college of chemistry and molecular engineering, Pkeing university yen wei chemistry department, drexel university, {13., PA 19104 usa

Poly (amidoamine) dendrimer G1, G2, G3, G4, and G5 were peripherally modified by reacting -NH2 groups with dansyl chloride (PAMAM-DNS G1, 2, 3, 4and 5). For comparison, G0 PAMAM dendrimer was modified with the same ch...

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National science Review 2024年第3期11卷 259-270页

作者： Jiajia Zhang Caichao Ye Genwang wei Liang Guo Yuhang Cai Zhi Li Xinzhi Wu Fangyi Sun Qikai Li Yupeng Wang Huan Li Yuchen Li Shuaihua Wang wei Xu Xuefeng Guo Wenqing Zhang weishu Liu department of Materials science and engineering Southern University of Science and Technology Academy for Advanced Interdisciplinary Studies and Guangdong Provincial Key Laboratory of Computational science and Material Design Southern University of Science and Technology department of Mechanical and Energy engineering Southern University of Science and Technology beijing National Laboratory for molecular sciences Key Laboratory of Organic Solids Institute of Chemistry Chinese Academy of Sciences college of chemistry and molecular engineering National Biomedical Imaging Centre Peking University Guangdong Provincial Key Laboratory of Functional Oxide Materials and Devices Southern University of Science and Technology

Enhancing the thermoelectric transport properties of conductive polymer materials has been a long-term challenge, in spite of the success seen with molecular doping strategies. However, the strong coupling between the thermopower and the electrical conductivity limits thermoelectric performance. Here, we use polaron interfacial occupied entropy engineering to break through this intercoupling for a PEDOT:PSS(poly（3,4-ethylenedioxythiophene）-poly（4-styrenesulfonate）) thin film by using photochromic diarylethene（DAE） dopants coupled with UV-light modulation. With a 10-fold enhancement of the thermopower from 13.5 μV K-1to 13..4 μV K-1and almost unchanged electrical conductivity, the DAE-doped PEDOT:PSS thin film achieved an extremely high power factor of 521.28 μW m-1K-2from an original value of 6.78 μW m-1K-2. The thermopower was positively correlated with the UV-light intensity but decreased with increasing temperature, indicating resonant coupling between the planar closed DAE molecule and PEDOT. Both the experiments and theoretical calculations consistently confirmed the formation of an interface state due to this resonant coupling. Interfacial entropy engineering of polarons could play a critical role in enhancing the thermoelectric performance of the organic film.

关键词： thermoelectric PEDOT: PSS interfacial occupied entropy resonant coupling UV-light modulation

Aggregation-induced emission luminogens for in vivo molecular imaging and theranostics in cancer

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Aggregate 2023年第5期4卷 34-62页

作者： Peili Cen Jiani Huang Chentao Jin Jing Wang yen wei Hong Zhang Mei Tian department of Nuclear Medicine and PET Center The Second Affiliated Hospital of Zhejiang University School of MedicineHangzhouZhejiangChina Institute of Nuclear Medicine and molecular Imaging of Zhejiang university HangzhouZhejiangChina Key Laboratory of Medical molecular Imaging of Zhejiang Province HangzhouZhejiangChina department of chemistry and the Tsinghua Center for Frontier polymer Research Tsinghua UniversityBeijingChina college of Biomedical engineering&Instrument science Zhejiang UniversityHangzhouZhejiangChina Key Laboratory for Biomedical engineering of Ministry of Education Zhejiang UniversityHangzhouZhejiangChina Human Phenome Institute Fudan UniversityShanghaiChina

Cancer is one of the most fatal diseases for ***-induced emission luminogens(AIEgens)have been recently used as molecular imaging or therapeutic agents in cancers,due to the advantages of large Stokes shift,high quantum yield,great biocompatibility,and strong *** can specifically target different types of cancer via diverse targeting ***-based fluorescence imaging,especially near-infrared imaging,demonstrated deep penetration and suitable signal-to-noise ratio,which allows reliable in vivo cancer *** with other imaging modalities,AIEgen-based multimodal imaging could provide multidimensional cancer hallmarks from different *** addition,AIEgenbased phototherapy can be used for photodynamic therapy and photothermal therapy,which facilitate ablation of cancer cells with good biosafety and high therapeutic effects in *** nanoparticles fabricated with some specific chemicals,drugs,or siRNA,could display synergistic therapeutic effects for *** paper comprehensively describes the current status and future perspectives of AIEgens,which have showed a great potential for the future preclinical and clinical translation on in vivo molecular imaging and theranostics in cancer.

关键词： aggregation-induced emission cancer near-infrared imaging phototherapy targeting strategy theranostics

What Can Topology Bring to chemistry?

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CCS chemistry 2024年第9期6卷 2084-2109页

作者： wei Wang Songtao Zhou Xiujun Yu Qing-Hui Guo Yanhang Ma Jie Song Liang Zhang Xuzhou Yan Lu Han Qing Liao Xiaopeng Li Wen-Bin Zhang Yiyong Mai Shaodong Zhang Shunai Che Hai-Bo Yang Xuefeng Fu Mei-Xiang Wang School of chemistry and molecular engineering East China Normal UniversityShanghai 200062 Hangzhou Institute of Medicine Chinese Academy of SciencesHangzhou 310022Zhejiang college of chemistry and Environmental engineering Shenzhen UniversityShenzhen 518060Guangdong MOE Key Laboratory of Bioorganic Phosphorous and Chemical Biology Department of ChemistryTsinghua UniversityBeijing 100084 School of Physical science and Technology and Shanghai Key Laboratory of High-Resolution Electron Microscopy ShanghaiTech UniversityShanghai 201210 School of chemistry and Chemical engineering Frontiers Science Center for Transformative MoleculesState Key Laboratory of Composite MaterialsShanghai Key Laboratory for Molecular Engineering of Chiral DrugsShanghai Jiao Tong UniversityShanghai 200240 School of Chemical science and engineering Tongji UniversityShanghai 200092 beijing Key Laboratory for Optical Materials and Photonic Devices Department of ChemistryCapital Normal UniversityBeijing 100048 beijing National Laboratory for molecular sciences Key Laboratory of Polymer Chemistry and Physics of Ministry of EducationCenter for Soft Matter Science and EngineeringCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871 department of Chemical sciences National Natural Science Foundation of ChinaBeijing 10085

The unique mathematical perspectives and principal concepts of topology have not only promoted the development of other branches of mathematics but have also deeply influenced other subjects,particularly physics and *** minireview aims to elucidate the substantial influence of topology on chemistry by critically examining both the contributions of topology to current chemical science and its potential future *** will discuss the topology of molecular structures and assemblies across various scales—from small molecules and mechanically interlocked molecules to polymers,biomacromolecules,and supramolecular *** discussion will include an exploration of cutting-edge techniques for characterizing topological features,underscoring the role of topology as a novel paradigm for the design and synthesis of new molecular ***,a critical analysis of topology’s role in the development of functional materials—such as photonic materials,polymers,biomacromolecules,and chiral materials—will demonstrate its emerging significance as a crucial parameter in unveiling novel properties and *** topology’s formidable potential,it is anticipated to be used increasingly to address pivotal challenges within chemistry and adjacent disciplines.

关键词： chemical topology topological invariants molecular graphs links and knots structureproperty relationship