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chinese Journal of polymer science 2001年第4期19卷 399-405页

作者： Zhen-hua yuan De-yan Shen ren-yuan Qian {3. physics laboratory center for molecular science, Institute of chemistry chinese academy of sciences,{13. chinese Acad Sci Inst Chem Ctr Mol Sci Polymer Phys Lab Beijing 100080 Peoples R China

Viscoelastic behavior of the non-Hooke deformation of amorphous PET film before yield was investigated in the temperature region 74-80.5 degreesC around the glass transition temperature. The film specimen was drawn to yield point followed by unloading to zero stress, then the residual deformation was held constant; while the subsequent evolution of the stress was recorded. An induction period was found in the course of stress evolution followed by a stress step-increase. The induction period decreases with increasing drawing temperature with an activation energy of 1.10 MJ/mol.K, which is attributed to the time needed for the relaxation of rubbery deformation through cooperative internal rotations. At temperatures lower than 74 degreesC, there is no stress increase or the induction period becomes too long to be observed. Thus the nature of anelasticity in the non-Hooke region before yielding is attributed to stress induced rubbery deformation. The experimental results are interpreted in terms of Perez' theological model of a series connected Hooks spring and a Voigt element consisting of a parallel connected elastic spring and a dashpot.

关键词： pre-yield deformation PET uniaxial drawing non-Hooke deformation viscoelasticity stress induced rubbery deformation

RHEOLOGICAL BEHAVIOR OF EPOXY RESIN WATERBORNE DISPERSIONS

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chinese Journal of polymer science 2001年第5期19卷 471-476页

作者： Zhen-zhong Yang yuan-ze Xu De-lu Zhao State Key laboratory of polymer {3. & chemistry, center for molecular science Institute of chemistry, chinese academy of sciences, beijing 100080 china chinese Acad Sci Inst Chem State Key Lab Polymer Phys & Chem Ctr Mol Sci Beijing 100080 Peoples R China

The waterborne dispersions of epoxy resin were prepared by the phase inversion emulsification technique. Rheological behavior and its relationship with the structural change of the systems were studied. It was shown that the concentrated dispersions were highly viscoelastic and pseudoplastic, which was attributed to the formation of a physical network among the waterborne particles via hydrogen bond. The dilute dispersions were Newtonian fluids. The discrete clusters composed of small waterborne particles were found in diluted dispersions. With increasing solid content, there existed a structural transition via percolation through a cluster-cluster aggregation mode to form the physical network, which was qualitatively evidenced by the TEM morphologies.

关键词： epoxy resin waterborne dispersion rheological behavior cluster-cluster aggregation percolation transition

Multiple Melting Endotherms of Syndiotactic Polystyrene in β Crystalline Form

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chinese Chemical Letters 2000年第4期11卷 367-368页

作者： Zhen Hua yuan De Yan SHEN (polymer physics {3., center for molecular science. Institute of chemistry. chinese academy of sciences, beijing 100080) chinese Acad Sci Inst Chem Ctr Mol Sci Polymer Phys Lab Beijing 100080 Peoples R China

A series of syndiotactic polystyrene (SPS) samples in β crystalline form were prepared by cooling from the melt at various cooling rates. The effects of cooling rate from the melt, and DSC heating rate on the multiple melting behaviors of β crystals were investigated by differential scanning calorimetry (DSC) and modulated differential scanning calorimetry (MDSC), from which the *** the multiple melting behavior was ascribed to the occurring of a recrystallization process.

关键词： Multiple melting behavior syndiotactic polystyrene recrystalliation.

GRAFTING-FROM AND GRAFTING-TO APPROACHES ON PREPARATION OF PET- PALYGORSKITE NANOCOMPOSITES

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GRAFTING-FROM AND GRAFTING-TO APPROACHES ON PREPARATION OF P...

Self-assembly Induced by Complexation of Diblock Copolyelectrolytes and Oppositely Charged Homopolymers

第三届工程塑料国际学术研讨会

作者： Xuepei yuan 1 2 Chuncheng Li 1 Guohu Guan1 Yaonan Xiao1 Dong Zhang1 1 laboratory of Engineering Plastics Joint laboratory of {3. science and Materials center for molecular science Institute of chemistry chinese academy of sciences beijing {13. P. R. china 2 Graduate School of the chinese academy of sciences beijing 10003. P.R china

＜正＞Compared with other polymers, such as polyamide and epoxide, etc., preparation of PET/clay nanocomposites is not successful. The relative higher processing temperature of PET usually results in

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chinese Journal of polymer science 2024年第9期42卷 1321-1332,I0006页

作者： Ling Zhao Zhi-yuan Yin Jia-Di Jiang Er-Qiang Chen Shuang Yang beijing National laboratory for molecular {3. Key Laboratory of Polymer Chemistry and Physics of Ministry of EducationCenter for Soft Mater Science and EngineeringCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing100871China beijing National laboratory for molecular {3. College of Chemistry and Molecular EngineeringPeking UniversityBeijing100871China

We investigate the solution self-assembly of a mixture of positively charged homopolymers and AB diblock copolymers,in which the A blocks are negatively charged,and the B blocks are *** electrostatic complexation between oppositely charged polymers drives the formation of many ordered *** microstructures and phase diagrams are calculated using self-consistent field theory(SCFT)based on an ion-pair model with an equilibrium constant K to characterize the st{3.gth of binding between positively and negatively charged *** effects of the charge ratio,representing the ratio of charges from the homopolymer over all charges from polymers in the system,on the ordered structure are systematically studied,both for hydrophobic and hydrophilic A *** charge ratio plays an important role in determining the phase boundaries in the phase diagram of salt concentration versus polymer *** also provide information about the varying tendency of the domain spacing and core size of the spherical phase when the charge ratio is changed,and the results are in good agreement with *** studies provide a deep understanding of the self-assembled microstructures of oppositely charged diblock copolymer-homopolymer systems.

关键词： Self-assembly Polyelectrolyte complexation Self-consistent field theory Ion-pair

Radiation-Assisted Synthesis of Crown Ether-Modified Covalent Organic Frameworks for Lithium Isotope Separation

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CCS chemistry 2024年第10期6卷 2594-2606页

作者： Shouchao Zhong Yue Wang Jianhui Lan Mingshu Xie Yiqian Wu Jiuqiang Li Fujian Liu Lilong Jiang Jing Peng Liyong yuan Maolin Zhai Weiqun Shi Radiochemistry and Radiation chemistry Key laboratory of Fundamental {3. Key Laboratory of Polymer Chemistry and Physics of the Ministry of EducationCollege of Chemistry and Molecular EngineeringBeijing National Laboratory for Molecular SciencesPeking UniversityBeijing 100871 National Engineering Research center of Chemical Fertilizer Catalyst College of Chemical EngineeringFuzhou UniversityFuzhou350002 Fujian laboratory of Nuclear Energy chemistry Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049

γ-ray radiation-induced grafting strategy was first employed to immobilize 4-aminobenzo-15-crown-5 onto a covalent organic framework(COF).This endeavor culminated in the successful synthesis of a class of two-dimensional crown ether-modified COFs(named[15C5]n%-(TzDa-G-x%)),marking the maiden utilization of COFs in the realm of^(6)Li/^(7)Li isotope *** COFs exhibited swifter adsorption kinetics than alternative *** them,[15C5]_(57%)-(TzDa-G-50%)with its excellent crystallinity,porosity,and stability exhibited the best performance in Li+adsorption and^(6)Li/^(7)Li isotope *** Li+adsorption in acetonitrile achieved a capacity of 3.6 mg·g^(−1)within 3. min and a saturation capacity of 7.3.mg·g^(−1).The single-stage separation factor of^(6)Li/^(7)Li isotopes was 1.014±*** results of dynamic adsorption column experiments showed that the packed column made of[15C5]_(57%)-(TzDa-G-50%)maintained stable performance during four cycles of Li+adsorptionelution,with over 99%Li+removal rate in *** crown ether-modified COF has potential application in^(6)Li/^(7)Li isotope separation,and this radiation-assisted synthesis strategy is expected to become universal in the modification of COFs for diverse applications.

关键词： covalent organic framework gamma radiation modification crown ether ^(6)Li/^(7)Li isotope separation adsorption column

Semitransparent organic photovoltaics enabled by transparent p-type inorganic semiconductor and near-infrared acceptor

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Journal of Energy chemistry 2024年第9期96卷 351-358页

作者： Xue Yan Jiayu Wang Wei He Top Archie Dela Peña Can Zhu Hailin Yu Yingyue Hu Cenqi Yan Shengqiang ren Xingyu Chen Zhe Wang Jiaying Wu Mingjie Li Jianlong Xia Lei Meng Shirong Lu Dewei Zhao Mikhail Artemyev Yongfang Li Pei Cheng College of polymer science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu 610065SichuanChina Department of Applied physics The Hong Kong Polytechnic UniversityKowloonHong Kong 999077China beijing National laboratory for molecular {3. CAS Key Laboratory of Organic SolidsInstitute of ChemistryChinese Academy of SciencesBeijing 100190China College of Materials science and Engineering&Engineering Research center of Alternative Energy Materials&Devices Ministry of EducationSichuan UniversityChengdu 610065SichuanChina Department of Material science and Technology Taizhou UniversityTaizhou 318000ZhejiangChina Advanced Materials Thrust Function HubThe Hong Kong University of Science and Technology(Guangzhou)Guangzhou 511400GuangdongChina State Key laboratory of Advanced Technology for Materials science and Processing Center of Smart Materials and DevicesWuhan University of TechnologyWuhan 430070HubeiChina Department of Civil1nd Environmental Engineering The Hong Kong University of Science and TechnologyHong Kong 999077China Research Institute for Physical Chemical Problems Belarusian State UniversityMinsk 220006Belarus

Semitransparent organic photovoltaics(STOPVs)have gained wide attention owing to their promising applications in building-integrated photovoltaics,agrivoltaics,and floating *** semiconductors with high charge carrier mobility usually have planar and conjugated structures,thereby showing strong absorption in visible *** this work,a new concept of incorporating transparent inorganic semiconductors is proposed for high-performance ***(I)thiocyanate(CuSCN)is a visible-transparent inorganic semiconductor with an ionization potential of 5.45 eV and high hole *** transparency of CuSCN benefits high average visible transmittance(AVT)of *** energy levels of CuSCN as donor match those of near-infrared small molecule acceptor BTP-eC9,and the formed heterojunction exhibits an ability of exciton *** mobility of CuSCN contributes to a more favorable charge transport channel and suppresses charge *** control STOPVs based on PM6/BTP-eC9 exhibit an AVT of 19.0%with a power conversion efficiency(PCE)of 12.7%.Partial replacement of PM6 with CuSCN leads to a 63.increase in transmittance,resulting in a higher AVT of 3..9%and a comparable PCE of 10.8%.

关键词： Copper(I)thiocyanate Inorganic semiconductor Semitransparent Organic photovoltaics Charge dissociation

Naphthalene diimide-based cathode interlayer material enables 20.2% efficiency in organic photovoltaic cells

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science china chemistry 2024年

作者： Yue Yu Jianqiu Wang Zhihao Chen Yang Xiao Zhen Fu Tao Zhang Haoyu yuan Xiao-Tao Hao Long Ye Yong Cui Jianhui Hou State Key laboratory of polymer physics and {3. Beijing National Laboratory for Molecular Sciences Institute of Chemistry Chinese Academy of Sciences University of chinese academy of sciences School of physics State Key Laboratory of Crystal Materials Shandong University beijing Advanced Innovation center for Soft Matter science and Engineering College of Materials Science and Engineering Beijing University of Chemical Technology School of Materials science and Engineering Tianjin University

Cathode interlayer(CIL) materials play an important role in improving the power conversion efficiency(PCE) of organic photovoltaic(OPV) cells. However, the current understanding of the structure-property relationship in CIL materials is limited, and systematic studies in this regard are scarce. Here, two new CIL materials, NDI-PhC 4 and NDI-PhC 6 were synthesized by varying the alkylamine chain length on the NDI-Ph core. Our investigation reveals a systematic variation in the physical and chemical properties of these materials with increasing alkylamine chain length. Specifically, we observe a sequential decrease in melting point and self-doping effect, accompanied by an enhancement in crystallinity. Among these CIL materials, NDI-PhC 4 has a notable balance across various performance metrics. It also exhibits excellent surface modification capabilities, leading to a low surface roughness. Consequently, OPV cells based on NDI-PhC 4 achieve a PCE of 20.2%, which is one of the highest reported efficiencies for OPV cells. In addition, the appropriate melting point of NDI-PhC 4 contributes to the excellent stability of OPV cells.

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Fluorination strategy enables greatly improved performance for organic solar cells based on polythiophene derivatives

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chinese Chemical Letters 2021年第7期32卷 2274-2278页

作者： Chenyi Yang Shaoqing Zhang Junzhen ren Pengqing Bi Xiaotao yuan Jianhui Hou School of chemistry and Biology Engineering University of Science and Technology BeijingBeijing 100083China State Key laboratory of polymer physics and {3. Beijing National Laboratory for Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing 100190China

The power conversion efficiencies(PCEs)of organic solar cells(OSCs)have reached 18%recently,which have already met the demand of practical ***,these outstanding results were generally achieved with donor-acceptor(D-A)type copolymer donors,which can hardly fulfill the low-cost largescale production due to their complicated synthesis ***,developing polymer donors with simple chemical structures is urgent for realizing low-cost ***(PT)derivatives are currently regarded as promising candidates for such kind of donor materials,which has been illustrated in many *** this work,two new alkylthio substituted PT derivatives,P3.1 and P3.2,were synthesized and tested as donors in the OSCs using Y5 as the accepto *** comparison,the introduction of fluorine atoms on the backbone of P3.2 can not only downshift the energy levels,but also greatly improve the phase separation morphologies of the active layers,which is ascribed to the enhanced aggregation effect and the reduced miscibility with the non-fullerene *** a result,the P3.2:Y5-based OSC exhibits a significantly improved PCE of 9.65%than that of P3.1:Y5-based one,indicating the important role of fluorination in the construction of efficient PT derivative donors.

关键词： Organic solar cells Polythiophene derivatives Fluorination Aggregation effect Miscibility

Multidisciplinary and multiscale nanoscience research roadmap based on large scientific facilities

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science china chemistry 2024年第8期67卷 2497-2523页

作者： yuan Zeng Shuhan Zhang Yuecong Guo Yalin Cong Xu Ding Peihua Li Yunxiang Lin Wenzhi ren Hui Su Weigang Sun Liuxin Xu Guikai Zhang Shihua Chen Yu Chen Weiren Cheng Shengqi Chu Yong Guan Jinru Han Jie Lin Hengjie Liu Zheyi Liu Pan Luo Fanchun Meng Sicong Qiao Zongyin Song Ying Wang Zhao Wu Chenyu Yang Meng Yang Shirui Yang Zi Yin Zhibin Yin Pengjun Zhang Hongyu Zhang Pingping Zheng Jia Zhou Wanlin Zhou Pengfei An He Cheng Chunhai Fan Xingjiu Huang Yong Lei Lina Li Mu Li Qinghua Liu Shuming Peng Li Song Zhihu Sun Yangchao Tian Fangjun Wang Lihua Wang Liming Wang Shiqiang Wei Aiguo Wu Chunlei Xiao Xueming Yang Panchao Yin Jing Zhang Mingxin Zhang Yaling Wang Chunying Chen CAS Key laboratory for Biomedical Effects of Nanomaterials and Nanosafety New Cornerstone Science LaboratoryNational Center for Nanoscience and TechnologyBeijing 100190China University of chinese academy of sciences Beijing 100049China National Synchrotron Radiation laboratory University of Science and Technology of ChinaHefei 230029China Institute of Solid State physics Hefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China Institutes of Physical science and Information Technology Anhui UniversityHefei 230601China Ningbo Key laboratory of Biomedical Imaging Probe Materials and Technology Zhejiang International Cooperation Base of Biomedical Materials Technology and ApplicationCAS Key Laboratory of Magnetic Materials and DevicesNingbo Cixi Institute of Biomedical EngineeringZhejiang Engineering Research Center for Biomedical MaterialsNingbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201China Advanced Energy science and Technology Guangdong laboratory Huizhou 516000China College of chemistry and Chemical Engineering Hunan Normal UniversityChangsha 410081China State Key laboratory of Luminescent Materials and Devices South China Advanced Institute for Soft Matter Science and TechnologySouth China University of TechnologyGuangzhou 510640China beijing Synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China CAS Key laboratory of Separation sciences for Analytical chemistry Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China State Key laboratory of molecular Reaction Dynamics Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China Institute of Advanced science Facilities Shenzhen 518107China State Key laboratory of Coal Conversion Institute of Coal ChemistryChinese Academy of SciencesTaiyuan 030001China State Key laboratory of Particle Detection and Electronics Institute of High Energy PhysicsChinese Acade

With the advancement of modern science and technology, large scientific facilities are increasingly oriented toward demand and application, and can be used for basic research as well as serving multiple disciplines. Developing large scientific facilities and related analytical technologies enhances understanding of large scientific facilities and popularizes their application in research across multiple disciplines. The combination of light or neutron sources from large scientific facilities and advanced analytical technologies can be achieved for materials structure information, dynamics study of chemical reactions, high dissociation of biomolecules, 3. visualization of energy materials or biological samples, etc. We first introduce the progress of domestic large scientific facilities of synchrotron radiation(SR) and free electron lasers(FELs) with different wavelengths and neutron *** further discuss the comparison between chinese and typical foreign facilities in X-ray radiation from X-ray tubes, synchrotrons, X-ray FELs, and neutron sources based on physical parameters of light and neutron sources. In addition, we focus on the technological progress and perspectives combined with advanced X-ray radiation and neutron sources of large scientific facilities in {3., especially in the nanoscience fields of energy catalysis and biological science. We hope that this roadmap will provide references on technology and methods to experimental users, as well as prospects for future development of technologies based on large research infrastructure facilities. Comprehensive studies and guidelines for basic research to practical application in various disciplines can be made with the assistance of large scientific facilities.

关键词： large scientific facilities synchrotron radiation FEL light sources neutron sources spectroscopic analysis methods X-ray imaging techniques structural information chemical dynamics