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Synthesis and Properties of High Performance Functional Polyimides Containing Rigid Nonplanar Conjugated Fluorene moieties

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Chinese Journal of Polymer Science 2019年第4期37卷 416-427,I0008页

作者： Yi-Wu Liu Li-Shuang Tang Lun-Jun Qu Si-Wei Liu Zhen-Guo Chi Yi Zhang Jia-Rui Xu PCFM Lab GD HPPC LabGuangdong Engineering Technology Research Centre for High-performance Organic and Polymer Photoelectric Functional FilmsState Key Laboratory of Optoelectronic Materials and TechnologiesSchool of ChemistrySun Yat-sen University Key Laboratory of Advanced Packaging Materials and Technology of Hunan Province School of Packaging and Materials EngineeringHunan University of Technology

A diamine(WuFDA) containing vertical rigid non-planar conjugated fluorene moiety and low polarizability group(C―F)was designed and synthesized through three steps of reactions(halogenated reaction, Suzuki coupling reaction, and reduction reaction).Four kinds of high performance functional polyimides(WuFPI-6 F, WuFPI-BP, WuFPI-BT, and WuFPI-PM) were thus prepared by the condensation polymerization of WuFDA with four commercial dianhydride 6 FDA, BPDA, BTDA, and PMDA, respectively. The polyimides exhibited low dielectric constant, excellent thermal stability, outstanding solubility, good film-forming property, and mechanical properties. The dielectric constants of the polyimides were in the range of 2.28-2.88(f = 10~4 Hz). The 5% weight-loss temperatures(Td 5%)in nitrogen were in the range of 555-584 °C, and the glass transition temperatures(T_g) were in the range of 408-448 °C. The weight loss of WuFPI-BP maintaining at 450 and 500 °C for half an hour was only 0.33% and 1.26%, respectively. All the WuFPIs could be dissolved in almost all organic solvents, even chloroform. The tensile strength and tensile modulus of these films were in the ranges of 78.6-85.7 MPa and 3.1-3.2 GPa, respectively. In addition, the polyimides displayed light color with special fluorescent and resistive switching(ON-OFF) characteristics; the maximum fluorescence emission was observed at 422-424 nm in NMP solution and at 470-548 nm in film state. The memory devices with the configuration of indium tin oxide/WuFPIs/aluminum(ITO/WuFPIs/Al) exhibited distinct volatile memory characteristics of static random access memory(SRAM), with an ON/OFF current ratio of 10~5-10~6. These functional polyimides showed attractive potential applications in the field of high performance flexible polymer photoelectronic devices or polymer memory devices.

关键词： Functional polyimide Fluorene derivative moieties Fluorescence polymer Low dielectric constant Thermal stability

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New ent-kaurane diterpenes with chiral epoxyangelate moieties from Wedelia prostrata

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Chinese Chemical Letters 2019年第2期30卷 451-453页

作者： Zhongnan Wu Yubo Zhang Wen Li Nenghua Chen Qianwen Niu Yingying Li Qingguo Li Dan Yang Yaolan Li Guocai Wang Institute of Traditional Chinese Medicine ξ Natural Products College of Pharmacy and Guangdong Province Key Laboratory of Pharmacodynamic Constituents of TCM and New Drugs ResearchJinan University Integrated Chinese and Western Medicine Postdoctoral Research Station Jinan University School of Pharmaceutical Sciences Guangzhou University of Chinese Medicine Department of Specific Diagnosis The 324th Military Hospital

Four new ent-kaurane diterpenes with chiral epoxyangelate moieties, (2′R,3′R)-3 a- (2′,3′-epoxyangeloyloxy)-kaur-16-en-19-oic acid (1), (2′S,3′S)-3 a- (2′,3′-epoxyangeloyloxy)-kaur-16-en-19-oic acid (2), (2′S,3′R)-3 a- (2',3'-epoxyangeloyloxy)-kaur-16-en-19-oic acid (3) and (2′R,3′S)-3α- (2′,3'-epoxyangeloyloxy)-kaur-16-en-19-oic acid (4), along with eight known diterpenes (5-12), were isolated from Wedelia prostrata. The absolute configurations of the new structures were determined by X-ray crystallography,ECD calculations and chemical methods. All compounds were evaluated for their cytotoxicity activities on human HepG-2 cells,with IC_(50) values of 11.72 ±0.22 μmol/L to 54.75±1.12 μmol/L.

关键词： Wedelia prostrata Chiral epoxyangelate moieties Ent-kaurane diterpenes Absolute configuration Cytotoxicity activities

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Study　on　the　Application　of　Polysiloxane　with　N－decanyltartrimide　moieties　in　Capillary　Electrophoresis

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Chinese Chemical Letters 1996年第9期7卷 829-830页

作者： Zhang, LF Hu, S Lu, XR Cheng, JK Chen, YY WUHAN UNIV DEPT CHEMWUHAN 430072PEOPLES R CHINA

Synthesis of polysiloxane with N-decanyltartrmide moieties and its application in coated capillary eletrophoresis are reported.

关键词： Application the Capillary moieties Polysiloxane

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Investigation on the structural feature of Shengli lignite

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International Journal of Mining Science and Technology 2018年第2期28卷 335-342页

作者： Zhang Yang-Yang Zong Zhi-Min Sun Yi-Bing Liu Fang-Jing Li Wei-Tu Wang Ya-Nan Wei Xian-Yong Key Laboratory of Coal Processing & Efficient Utilization Ministry of Education China University of Mining & Technology

The extraction residue from Shengli lignite was sequentially dissolved in cyclohexane, benzene, methanol, ethanol, and isopropanol in an autoclave at 320℃ to afford soluble portions(SPs) 1–5(SP_1-SP_5) and the final residue(FR). The total yield of SP_1-SP_5 is ca. 55.1%. The FR was subjected to ruthenium ioncatalyzed oxidation and the resulting products were isolated from the reaction mixture and *** the esterified products and SP_1-SP_5 were analyzed with a gas chromatograph/mass *** total, 342 compounds were identified in SP_1-SP_5. They can be classified into normal alkanes, branched alkanes, alkenes, alkanedienes, arenes, alkanols, methylcycloalkanes, alkenols, alkylbenzenemethanols,arenols, anisol and substituted anisols, polymethyldihydrobenzofurans, arenofurans, dibenzofurans,ethoxymethylbenzenes, aldehydes, ketones, esters, nitrogen-containing organic compounds, sulfurcontaining organic compounds, and other compounds. Among the compounds, arenols are predominant in SP_1 and SP_2 and the main compounds in SP_3, while the main compounds in SP_4 and SP_5 are esters and arenes, respectively. According to the esterified products identified, the products from the FR oxidation can be grouped into non-benzene ring carboxylic acids(NBCAs) and benzenepolycarboxylic acids(BPCAs). The total yield of BPCAs is much higher than that of NBCAs, suggesting that the FR is rich in condensed aromatic moieties.

关键词： Lignite Arenols Esters Arenes Condensed aromatic moieties

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