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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, philadelphia, pa 19104, usa department of polymer science & engineering College of Chemistry & Molecular Engineering Peking University 北京 100871 department of chemistry Drexel University Philadelphia PA 19104 美国

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 philadelphia, pa 19104 usa department of polymer science & engineering College of Chemistry & Molecular Engineering Peking University 北京 100871 department of chemistry Drexel University 美国 Philadelphia PA 19104

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

SYNTHESIS AND BIOTECHNOLOGICAL APPLICATIONS OF VINYL polymerINORGANIC HYBRID AND MESOPOROUS MATERIALS

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Chinese Journal of polymer science 2000年第1期18卷 1-7页

作者： yen wei Kun-yuan Qiu department of chemistry, drexel university, philadelphia, Pennsylvania 19104, usa department of polymer science and engineering, peking university, beijing 100871, china drexel university 美国北京大学高分子科学与工程系北京

We describe the sol-gel synthesis of a new family of organic-inorganic hybrid materials, in which various vinyl polymers are covalently bonded to and uniformly distributed in inorganic oxide matrices. The materials can be tailored to have both good toughness and hardness while maintaining excellent optical transparency. Doping the sol-gel metal oxides with optically active compounds such as D-glucose results in new optical rotatory composite materials. Removal of the dopant compounds from the composites affords mesoporous oxide materials; which represents a new, nonsurfactant-templated route to mesoporous molecular sieves. We have successfully immobilized a series of enzymes and other bioactive agents in mesoporous materials. Catalytical activities of the enzyme encapsulated in mesoporous materials were found to be much higher than those encapsulated in microporous materials.

关键词： vinyl polymer-inorganic hybrid materials mesoporous materials sol-gel process biotech-nological applications

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. 北京大学北京 drexel university 美国

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 department of polymer science and engineering College of Chemistry and Molecular Engineering Peking University 北京 100871 department of chemistry Drexel University 美国 Pennsylvania

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

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 department of polymer science and engineering College of Chemistry and Molecular Engineering Peking University National Research Institute for Family Planning

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 ...

In situ sulfur-doped mesoporous tungsten oxides for gas sensing toward benzene series

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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Chinese Chemical Letters 2024年第7期35卷 502-507页

作者： Yu Deng Yan Liu Yonghui Deng Jinsheng Cheng Yidong Zou wei Luo State Key Laboratory for Modification of Chemical Fibers and polymer Materials College of Materials Science and EngineeringDonghua UniversityShanghai 201620China department of chemistry State Key Laboratory of Molecular Engineering of PolymersShanghai Key Laboratory of Molecular Catalysis and Innovative MaterialsiChEMFudan UniversityShanghai 200433China department of polymeric Materials School of Materials Science and EngineeringTongji UniversityShanghai 201804China Henry-Fork School of Food sciences Shaoguan UniversityShaoguan 512005China State Key Lab of Transducer Technology Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 200050China

Benzene series as highly toxic gases have inevitably entered human life and produce great threat to human health and ecological environment,and thus it is distinctly meaningful to monitor benzene series with quickly,real-time and efficient ***,novel sulfur-doped mesoporous WO_(3)materials were synthesized via classical in-situ solvent evaporation induced co-assembly strategy combined with doping engineering,which possessed highly crystallized frameworks,high specific surface area(40.9–63.8 m^(2)/g)and uniform pore size(~18 nm).Benefitting from abundant oxygen vacancy and defects via S-doping,the tailored mesoporous S/m WO_(3)exhibited excellent benzene sensing performance,including high sensitivity(50 ppm vs.48),low detection limit(ca.500 ppb),outstanding selectivity and favorable *** addition,the reduction of band gap resulted from S-doping promotes the carrier migration in the sensing materials and the reaction at the gas–solid sensing *** provides brand-new approach to design sensitive materials with multiple reaction sites.

关键词： Mesoporous materials Benzene series Tungsten oxides Sulfur doping Gas sensor

Precise Planar-Twisted molecular engineering to Construct Semiconducting polymers with Balanced Absorption and Quantum Yield for Efficient Phototheranostics

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Research 2024年第2期2023卷 227-238页

作者： Xiang Su Zhirong Bao wei Xie Deliang Wang Ting Han Dong Wang Ben Zhong Tang Center for AIE Research Shenzhen Key Laboratory of Polymer Science and TechnologyGuangdong Research Center for Interfacial Engineering of Functional MaterialsCollege of Materials Science and EngineeringShenzhen UniversityShenzhen 518060China School of Biomedical and Pharmaceutical sciences Guangdong University of TechnologyGuangzhou 510006China department of Radiation and Medical Oncology Hubei Key Laboratory of Tumor Biological BehaviorsHubei Cancer Clinical Study CenterZhongnan Hospital of Wuhan UniversityWuhan 430071China department of Materials chemistry Huzhou UniversityHuzhou 313000China School of science and engineering Shenzhen Institute of Aggregate Science and TechnologyThe Chinese University of Hong KongShenzhenGuangdong 518172China

Semiconducting polymers(SPs)have shown great feasibility as candidates for near-infrared-II(NIR-Ⅱ)fluorescence imaging-navigated photothermal therapy due to their strong light-harvesting ability and flexible ***,the fluorescence signal of traditional SPs tends to quench in their aggregate states owing to the strongπ-πstacking,which can lead to the radiative decay pathway shutting *** address this issue,aggregation-induced emission effect has been used as a rational tactic to boost the aggregate-state fluorescence of NIR-Ⅱ*** this contribution,we developed a precise molecular engineering tactic based on the block copolymerizations that integrate planar and twisted segments into one conjugated polymer backbone,providing great flexibility in tuning the photophysical properties and photothermal conversion capacity of *** monomers featured with twisted and planar architectures,respectively,were tactfully incorporated via a ternary copolymerization approach to produce a series of new *** optimal copolymer(SP2)synchronously shows desirable absorption ability and good NIR-Ⅱquantum yield on the premise of maintaining typical aggregation-induced emission characteristics,resulting in balanced NIR-Ⅱfluorescence brightness and photothermal ***-dispersible nanoparticles fabricated from the optimal SP2 show efficient photothermal therapeutic effects both in vitro and in *** in vivo investigation reveals the distinguished NIR-Ⅱfluorescence imaging performance of SP2 nanoparticles and their photothermal ablation toward tumor with prominent tumor accumulation ability and excellent biocompatibility.

关键词： property conducting twisted

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

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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 135.4 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