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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, China. 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, China 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

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, China department of chemistry, drexel university,{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

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, China department of chemistry drexel university{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

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

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FLUORESCENCE AND ELECTROCHEMICAL BEHAVIOR OF DANSYL-SHELLED ...

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

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, philadelphia, 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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Aggregate

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

polymerizable AEE-active Dye with Optical Activity for Fluorescent Nanoparticles Based on Phenothiazine:Synthesis,Self-assembly and Biological Imaging

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Chinese Journal of polymer science 2021年第11期39卷 1431-1440页

作者： Zeng-Fang Huang Ya-Li Chen Chao-Yue Zhou Yan-Hong Li Mei Li Xiao-Bo Liu Liu-Cheng Mao Jin-Ying Yuan Lei Tao yen wei School of Materials&Food engineering Zhongshan InstituteUniversity of Electronic Science&Technology of ChinaZhongshan 528402China School of Materials and Energy University of Electronic Science&Technology of ChinaChengdu 610054China department of chemistry the Tsinghua Center for Frontier Polymer ResearchTsinghua UniversityBeijing 100084China

In consideration of various advantages such as less harm,higher sensitivity,and deeper imaging depth,etc.,AIE materials with longwave emission are attracting extensive attention in the fields of vascular visualization,organelle imaging,cells tracker,forensic detection,bioprobe and chemosensor,*** this work,a novel fluorescent(R)-PVHMA monomer with chirality and aggregation-induced emission enhancement(AEE)characteristics was acquired through enzymatic transesterification reaction basing on phenothiazine,and its[α]D25℃value was about-6.39°with a 3.08 eV bandgap calculated by the quantum ***,a series of PEG-PVH1 and PEG-PVH2 copolymers with chirality feature were achieved through RAFT polymerization of the obtained(R)-PVHMA and PEGMA with various feed *** the feed molar ratio of(R)-PVHMA increased from 21.5%to 29.6%,its actual molar fractions in the PEG-PVH1 and PEG-PVH2 copolymers accordingly increased from 18.1%to 25.7%.The molecular weight of PEG-PVH1 was about 2.2×10^(4) with a narrow PDI,and their kinetics estimation showed a first-order quasilinear *** aqueous solution,the amphiphilic copolymers PEG-PVH could self-assemble into about 100 nm *** a 90%water solution of H_(2)O and THF mixture,the fluorescence intensity had the maximum value,and the emission wavelength presented at 580 and 630 *** investigation of cytotoxicity and cells uptake showed that PEG-PVH FONs performed outstanding biocompatibility and excellent cells absorption effects,which have great potential in bioimaging application.

关键词： AEE dye Optical activity RAFT polymerization Long-wave emission Biological imaging

Modified Triphenylmethane-based Polyimides with Improved Optical,Dielectric and Solubility Properties via Post-polymerization Modification

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高分子科学:英文版 2023年第10期41卷 1609-1616页

作者： Yan-Cheng Wu Guo-Tao Huang Man-Yu Lian Rui Liang Hong-Lin Deng Feng Gan Yang-Fan Zhang Ning-Bo Yi Li-Yong Tian Chun-Ping Ma yen wei School of Textile Materials and engineering Wuyi UniversityJiangmen529020China department of chemistry and the Tsinghua Center for Frontier polymer Research Tsinghua UniversityBeijing100084China

A family of new triphenylmethane(TPM)-based polyimides(PIs)containing bulky tert-butyldimethylsiloxy(TBS)side-groups(PI-TPMOSis)has been prepared by a post-polymerization modification via a simple silyl ether reaction of TPM-based PIs containing hydroxyl(OH)groups(PI-TPMOHs).The attachment of TBS side-groups in PI-TPMOSis can be achieved up to 100%,as confirmed by the 1H-NMR and IR *** to the presence of the TPM structure,PI-TPMOSi films still display the excellent thermal stability with high glass transition temperature(Tg)of 314–351°C and high degradation temperature(Td5%)of 480–501°*** is quite remarkable that the introduction of TBS side-groups into PI-TPMOSi chains results in more superior optical,dielectric and solubility properties in comparison with the precursor PI-TPMOH films,probably due to the reductions of the packing density and charge-transfer complexes(CTCs)*** optical transmittance at 400 nm(T400)of PI-TPMOSi films is significantly increased from 45.3%–68.8%to 75.4%–81.6%of the precursor PI-TPMOH *** dielectric constant(Dk)and dissipation factor(Df)at 1 MHz of PI-TPMOSi films are reduced from 4.11–4.40 and 0.00159–0.00235 to 2.61–2.92 and 0.00125–0.00171 of the precursor PI-TPMOH films,*** the molecular design and simple preparation method,this study provides an effective approach for enhancement of various properties of PI films for microelectronic and photoelectric engineering applications.

关键词： Triphenylmethane-based polyimides Post-polymerization modification High Tg High optical transparence Low Dk

Electrodes with Electrodeposited Water-excluding polymer Coating Enable High-Voltage Aqueous Supercapacitors

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Research 2020年第1期2020卷 711-723页

作者： Wujie Dong Tianquan Lin Jian Huang Yuan Wang Zhichao Zhang Xin Wang Xiaotao Yuan Jie Lin I-wei Chen Fuqiang Huang State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050China State Key Laboratory of Rare Earth Materials chemistry and Applications College of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China department of Materials science and engineering University of PennsylvaniaPhiladelphiaPA 19104USA

Aqueous supercapacitors are powerful energy sources,but they are limited by energy density that is much lower than lithium-ion *** raising the voltage beyond the thermodynamic potential for water splitting(1.23 V)can boost the energy density,there has been much effort on water-stabilizing salvation additives such as Li_(2)SO_(4) that can provide an aqueous electrolyte capable of withstanding~1.8 *** by the first-principles calculations that reveal water can promote hydrogen and oxygen evolution reactions,here,we pursue a new strategy of covering the electrode with a dense electroplated polymerized polyacrylic acid,which is an electron insulator but a proton conductor and proton *** combined effect of salvation and coating expands the electrochemical window throughout pH 3 to pH 10 to 2.4V for both fast and slow proton-mediated redox *** allows activated carbon to quadruple the energy density,a kilogram of nitrogen-doped graphene to provide 127 Watt-hour,and both to have improved endurance because of suppression of water-mediated ***,aqueous supercapacitors can now achieve energy densities quite comparable to that of a lithium-ion battery,but at 100 times the charging/discharging speed and cycle durability.

关键词： lithium durability battery