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Science China(Technological Sciences) 2011年第9期54卷 2310-2314页

作者： WU MaoYang LI Wei QIU YiJiao FU JunWei JIANG YaDong School of Optoelectronic Information University of Electronic Science and Technology of China Chengdu 610054 China State Key Laboratory of Electronic Thin Films and Integrated Devices University of Electronic Science and Technology of China Chengdu 610054 China

hydrogen bonding configurations and hydrogen content in hydrogenated amorphous silicon (a-Si:H) thin films prepared at different precursor gas temperatures with undiluted silane have been investigated by means of Fourier transform infrared (FTIR) *** results show that the gas temperature before precursor gases entering the glow-discharge zone re-markably influences the hydrogen bonding configurations and the hydrogen content in a-Si:H thin *** hydrogen content decreases from 18% down to 11% when increasing the gas temperature from room temperature (RT) to 433 ***,the clustered hydrogen at the physical film surface or at the internal surfaces of the microvoids decreases,indicating that a-Si:H thin films are densified at higher precursor gas *** a-Si:H thin films deposited at gas temperature of 433 K,the isolated silicon-hydrogen bonding configuration is predominant in the testing films.

关键词： a-Si:H thin film gas temperature hydrogen bonding FTIR PECVD

hydrogen bonding-induced oxygen clusters and long-lived room temperature phosphorescence from amorphous polyols

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Chinese Chemical Letters 2023年第1期34卷 187-191页

作者： Ya-Ling Wang Kang Chen Hai-Ru Li Bo Chu Zishan Yan Hao-Ke Zhang Bin Liu Shengliang Hu Yongzhen Yang School of Energy and Power Engineering North University of ChinaTaiyuan 030051China MOE Key Laboratory of Interface Science and Engineering in Advanced Materials Taiyuan University of TechnologyTaiyuan 030024China Department of Polymer Science and Engineering MOE Key Laboratory of Macromolecular Synthesis and FunctionalizationZhejiang UniversityHangzhou 310027China Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering Taiyuan 030032China

Developing non-conjugated luminescent polymers(NCLPs)with fluorescence and long-lived roomtemperature phosphorescence is of great significance for revealing the essence of NCLPs luminescence,which has gradually attracted the attention of researchers in recent ***,polymethylol(PMO)and poly(3-butene-1,2-diol)(PBD)with polyhydroxy structures were prepared and their luminescence behaviors were investigated to reveal the clusteroluminescence(CL)*** with polyvinyl alcohol with non-luminescent behavior,PMO and PBD exhibit cyan-blue fluorescence with quantum yields of ca.12%and green room-temperature phosphorescence with lifetimes of ca.89 ms in the solid *** fluorescence and phosphorescence exhibit typical excitation-dependent CL *** and theoretical analyses show that the strong hydrogen-bonding interaction of PMO and PBD greatly promotes the formation of oxygen clusters and the through-space n-n interaction of oxygen atoms,enabling fluorescence and phosphorescence *** results have enormous implications for understanding the CL mechanism of NCLPs and provide a new polymer design strategy for the rational design of novel NCLPs materials.

关键词： Clusteroluminescence Through-space interactions Polymethylol Poly(3-butene-1,2-diol) hydrogen bonding Polymerization

hydrogen bonding-Assisted Synthesis of Silica/Oxidized Mesocarbon Microbeads Encapsulated in Amorphous Carbon as Stable Anode for Optimized/Enhanced Lithium Storage

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Transactions of Tianjin University 2020年第1期26卷 13-21页

作者： Zongjie Cao Huitian Liu Wenlong Huang Peng Chen Yuansheng Liu Yu Yu Zhongqiang Shan Shuxian Meng School of Chemical Engineering and Technology Tianjin University

The practical application of silica-based composites as an alternative to commercial graphite anode materials is hampered by their large volumetric expansion,poor conductivity,and low Coulombic *** this work,a novel silica/oxidized mesocarbon microbead/amorphous carbon(SiO2/O’MCMB/C)hierarchical structure in which SiO2 is sandwiched between spherical graphite and amorphous carbon shell was succes sfully fabricated through hydrogen bonding-assisted self-assembly and post-carbon coating *** obtained three-layer hierarchical structure effectively accommodates the volumetric expansion of SiO2 and significantly enhances the electronic conductivity of composite ***,the outer layer of amorphous carbon effectively increases the diffusion rate of lithium ions and promotes the formation of stable SEI *** a result,the SiO2/O’MCMB/C composite exhibits superior electrochemical performance with a reversible capacity of 459.5 mA h/g in the first cycle,and the corresponding Coulombic efficiency is 62.8%.After 300 cycles,the capacity climbs to around 600 mA h/*** synthetic route provides an efficient method for preparing SiO2 supported on graphite with excellent electrochemical performance,which is likely to promote its commercial applications.

关键词： hydrogen bonding Silica Oxidized mesocarbon microbead Anode material

hydrogen bonding in hydrogenated Amorphous Germanium

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Tsinghua Science and Technology 2004年第2期9卷 177-180页

作者： M. S. Abo-Ghazala S. Al Hazmy Physics Department Faculty of Science Menoufia University Sheben El-Koom EgyptChemistry Department Faculty of Science Sana University Yemen

Thin films of hydrogenated amorphous germanium (a-Ge:H) were prepared by radio frequency glow discharge deposition at various substrate temperatures. The hydrogen distribution and bonding struc-ture in a-Ge:H were discussed based on infrared absorption data. The correlation between infrared absorp-tion spectra and hydrogen effusion measurements was used to determine the proportionality constant for each vibration mode of the Ge-H bonds. The results reveal that the bending mode appearing at 835 cm1 is associated with the Ge-H2 (dihydride) groups on the internal surfaces of voids. While 1880 cm1 is assigned to vibrations of Ge-H (monohydride) groups in the bulk, the 2000 cm1 stretching mode is attributed to Ge-H and Ge-H2 bonds located on the surfaces of voids. For films associated with bending modes in the infrared spectra, the proportionality constant values of the stretching modes near 1880 and 2000 cm1 are found to be lower than those of films which had no corresponding bending modes.

关键词： hydrogenated amorphous germanium hydrogen bonding film

Catalysis and Inhibition of Benzimidazole Units on Thermal Imidization of Poly(amic acid) via hydrogen bonding Interactions

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Chinese Journal of Polymer Science 2015年第4期33卷 621-632页

作者： Hui-na Wang Ming-xi Yang Long-bo Luo Jie-yang Huang Ke Li Xu Wang Yan Feng 刘向阳 State Key Laboratory of Polymer Materials Engineering College of Polymer Science and EngineeringSichuan University

The effect of benzimidazole units on thermal imidizaiton was studied when they were introduced into the main chain of poly（amic acid）（PAA）. The thermal imidization process of PAA-PABZ synthesized by 3,3＇,4,4＇- biphenyltetracarboxylic dianhydride （BPDA） and 2-（4-aminophenyl）-5（6）-aminobenzimidazole （PABZ） was studied by TGA, DSC, DMA, FTIR and in situ FTIR. The results of FTIR and in situ FTIR indicate benzimidazole units act as an ＂in situ＂ catalyst to accelerate thermal imidization of PAA to polyimide （PI） when the temperature is lower than 170℃. FTIR and ~H-NMR results demonstrate that in situ catalysis is caused by the hydrogen bonding interactions between C=N of benzimidazole and -NH- in -CONH- of PAA and the semi-ionization of the H in imidazole ring of benzimidazole. However, when the imidization temperature is higher than 170℃, the thermal imidization process is inhibited. DMA and in situ FTIR results illustrate that the decreased mobility of PI-PABZ macromolecular chains and the reduced reactive ability of anhydride formed during the intramolecular breakdown of polymer chains lead to the inhibition of thermal imidization process.

关键词： Benzimidazole hydrogen bonding Catalysis Inhibition Polyimide.

Halogen bonding or hydrogen bonding between 2,2,6,6-Tetramethyl- piperidine-noxyl Radical and Trihalomethanes CHX3 （X=CI, Br, I）

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Chinese Journal of Chemical Physics 2013年第2期26卷 172-180,I0003页

作者：赵晓冉庞雪阎晓青晋卫军北京师范大学化学学院北京100875

The halogen and hydrogen bonding complexes and trihalomethanes （CHX3, X=C1, Br, I） are between 2,2,6,6-tetramethylpiperidine-noxyl simulated by computational quantum chem- istry. The molecular electrostatic potentials, geometrical parameters and interaction energy of halogen and hydrogen bonding complexes combined with natural bond orbital analysis are obtained. The results indicate that both halogen and hydrogen bonding interactions obey the order CI〈Br〈I, and hydrogen bonding is stronger than the corresponding halogen bond- ing. So, hydrogen bonding complexes should be dominant in trihalomethanes. However, it is possible that halogen bonding complex is competitive, even preponderant, in triiodomethane due to the similar interaction energy. This work might provide useful information on specific solvent effects as well as for understanding the mechanism of nitroxide radicals as a bioprobe to interact with the halogenated compounds in biological and biochemical fields.

关键词： Halogen bonding hydrogen bonding Theoretical study Nitroxide radical Natural bond orbital

Synthesis and Structure of a La(Ⅲ) Complex of 1,10-Phenanthroline-2,9-dicarboxylate:a Three-dimensional Network via hydrogen bonding Interactions

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Chinese Journal of Structural Chemistry 2008年第2期27卷 137-142页

作者： GAO Qian XIE Ya-Bo CHEN Yuan WANG Dao College of Environmental and Energy Engineering Beijing University of Technology Beijing 100022 China

A new La（Ⅲ） complex, {[La（L）（NO3）（H2O）3]·H2O}n （L = 1,10-phenanthroline- 2,9-dicarboxylate）, has been synthesized and structurally determined by X-ray diffraction analysis. The complex crystallizes in the monoclinic system, space group P21/c with a = 7.7358（17）, b = 8.1664（18）, c = 28.271（6） A, β= 95.184（4）°, V= 1778.6（7） A3, Z = 4, C14H14LaN3O11, Mr = 539.19, Dc = 2.014 g/cm^3, μ= 2.471 mm^-1, F（000） = 1056, the final R = 0.0350 and wR = 0.0659. In this complex, each metal center adopts a ten-coordination geometry formed by two N atoms from a ligand L and eight O atoms from three H2O molecules, a nitrate ion and carboxylates of two ligands. Each ligand adopts a N2,O3-pentdentate coordination mode using two N and two O atoms chelating a La（Ⅲ）, and using another O atom of carboxylate to bridge another La（Ⅲ） center resulting in a 1D helical chain molecule. Intermolecular strong O-H…O and weak C-H…O hydrogen bonds extend the 1D chain structure into a 3D supramolecular architecture.

关键词： hydrogen bonding 1,10-phenanthroline-2,9-dicarboxylate La(Ⅲ) complex,synthesis

Chain Extender-induced hydrogen bonding Organization Determines the Morphology and Properties of Thermoplastic Polycarbonate Polyurethane

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Chinese Journal of Polymer Science 2024年第1期42卷 87-96,I0009页

作者： Yi-Lang Qin Ping Zhu Chen-Xi Ouyang Xia Dong Fuwai Hospital Chinese Academyof Medical Sciences&Peking Union Medical College/National Center for Cardiovascular DiseasesBejing 100037China CASKey Laboratoryof Engineering Plastics CAS Research/Education Centerfor Excellence in Molecular SciencesInstitute ofChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Thermoplastic polycarbonate polyurethanes(PCUs) are multiblock copolymers that have been applied for medical devices for long time. Aliphatic diols are common chain extenders(CE) involved in the composition of the hard segments of PCU. However, limited knowledge was discovered about how the chemical structure of CE affects the hydrogen bonding organization within PCUs and their mechanical *** investigate this problem, a group of PCUs were synthesized respectively by extending the polymer chain with 1,4-butanediol(BDO),aminoethanol(MEA), ethanediol(EO) as three kinds of chain extenders. Tiny differences in the CE chemical structure results in remarkable variations in phase separation, condensed morphologies, thermal and mechanical properties, which are characterized by Fourier transform infrared spectrometer, atomic force microscopy, small-angle X-ray scattering, differential scanning calorimetry, and tensile tests. The microstructural evolution during unilateral deformation and the different mechanism induced by the different CEs was probed and unveil by in situ wide-and small-angle X-ray diffraction. Symmetry of CE can improve the organization of the hydrogen bonding. The coherence strength of the urethane/urea group also plays a key role by comparing the two PCUs with ethanediol and aminoethanol.

关键词： Thermoplastic polycarbonate polyurethane Chain extender hydrogen bonding Mechanical properties

Influence of hydrogen bonding on the Temperature-Accelerated Hydrolysis of Silicone Based Polyetherurethane

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Chinese Journal of Polymer Science 2023年第8期41卷 1230-1237,I0007页

作者： He-Cheng Wu Shu-Ren Shao Shuo-Hong Dong Ao Wang Zhen Li Xiang-Long Han Feng Luo Jie-Hua Li Dai-Guo Zhao Wan-Ling Lan Hong Tan College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringMed-X Center for MaterialsSichuan UniversityChengdu 610065China State Key Laboratory of Oral Diseases National Clinical Research Center for Oral DiseasesWest China Hospital of StomatologySichuan UniversityChengdu 610041China Sichuan Institute for Food and Drug Control Chengdu 611731China

Temperature-accelerated in vitro degradation was established to estimate the longevity of polyurethane applied for long-term ***,the prediction did not correlate well with the data from clinical explants and the rationality of accelerated in vitro test is still in a controversial due to the *** improve the accuracy of the in vitro prediction,the influence of hydrogen bonding(HB)on the accelerated hydrolysis of silicone based polyetherurethans(SPEUs)extended with three side *** the temperature-controlled FTIR and the physical properties after temperature-accelerated in vitro degradation,it was demonstrated that side chain could increase the degree of hydrogen bond dissociation at higher temperature,resulting in the decrease of the calculated activation energy(E_(a))of *** low temperatures,changes in surface morphology and molar mass of PEUs are minimal and HB are less easily dissociated,which had barely impact on the hydrolysis *** was proposed that the E_(a) will not be impacted and that the accuracy of prediction will be increased if the acceleration temperature is lower than 70℃ and HB change is less than 15%.

关键词： Polyether urethane Polydimethylsiloxane Activation energy hydrogen bonding Hydrolysis resistance

High Damping and Mechanical Properties of hydrogen-bonded Polyethylene Materials with Variable Contents of Hydroxyls:Effect of hydrogen bonding Density

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Chinese Journal of Polymer Science 2017年第5期35卷 649-658页

作者： Lei Kan Xiao Ouyang Shan Gao Rui Li 马宁 Shi-hui Han 魏浩 Lian-he Liu College of Material Science and Chemical Engineering Harbin Engineering University

hydrogen bonding is considered to have significant effect on the interaction between polymeric chains and on the viscoelasticity of the polymeric materials. In this paper, we attempt to discuss the relationship between hydrogen bonding density and damping behavior and mechanical properties of polyethylene-based polymeric materials. For this reason, a series of pendant chain hydrogen bonding polymers （PCHBP） with different hydrogen bonding density （HBD） were prepared by quantitatively changing the content of pendent hydroxyl groups on the main chain of polyethylene. It was found that PCItBP with low HBD showed similar properties to polyethylene, indicating that the property of the materials was dependent mainly on the structure of the main chain. However, PCHBP with high HBD exhibited two tandpeaks and a platform of loss modulus as well as a high storage modulus （about 400 MPa） at the second tand peak temperature, demonstrating that a polymeric material with high strength and damping properties was obtained. More importantly, the maximum of loss modulus showed a linear increase with the HBD, indicating that a higher HBD greatly improved the damping properties of the polymeric materials.

关键词： Hydroxyls Polyethylene hydrogen bonding Polymer damping