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Chinese Journal of Polymer Science 2015年第6期33卷 815-822页

作者： Xiu-bo Jiang Qing-fei Zhang 贺爱华 Key Laboratory of Rubber-Plastics Ministry of Education/Shandong Provincial Key Laboratory of Rubber-PlasticsSchool of Polymer Science and EngineeringQingdao University of Science and Technology

Abstract Two series of trans-1,4-poly（butadiene-co-isoprene） copolymers （TBIR） were prepared using the catalyst system TiCl4/MgCl2-Al（i-Bu）3 at different reaction temperatures. All dyad and triads sequence distributions, the number-average sequence length and the sequence concentration of the copolymers were calculated according to 13C-NMR spectra. The influences of temperature and initial molar ratio of butadiene to isoprene （Bd to Ip） on the distribution of the chain segments in the TBIR copolymers were discussed. The correlation of copolymer compositions and thermal properties.were also evaluated, which facilitated the understanding of controlling the degree of crystallinity and the transition tempera^re by changing Bd content and temperature.

关键词： Trans-1,4- Isoprene Butadiene Copolymer thermal properties.

A QUICK AND GREEN IONIC LIQUID-MEDIATED APPROACH FOR THE SYNTHESIS OF HIGH-PERFORMANCE, ORGANOSOLUBLE AND thermalLY STABLE POLYIMIDES

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Chinese Journal of Polymer Science 2013年第4期31卷 679-690页

作者： Mehdi Taghavi Mousa Ghaemy Marjan Hassanzadeh Seyed Mojtaba Amini Nasab Polymer Chemistry Research Laboratory Department of ChemistryUniversity of MazandaranBabolsar 47416-95447Iran

Three diamine monomers with different derivatives of imidazole heterocyclic ring and meta-linked aryl ethers were synthesized and used in polycodensation reaction with various commercial dianhydrides for preparation of a series of novel poly（ether-imide）（PEI）s. The polycodensation reactions were carried out by using conventional method and in a green medium of ionic liquid （IL） without using NMP-pyridine-acetic anhydride. The PEIs were obtained in good yields （80%-96%） with moderate viscosity （0.48-0.66 dL/g） in a shorter reaction time （10 h） in IL as compared with the conventional method （36 h）. All of the polymers were amorphous in nature, showed excellent solubility in amide-type polar aprotic solvents with ability to form tough and flexible films, and excellent thermal stability with Tgs in the range of 212-340℃ and 10% weight loss temperature （T10） up to 570℃ in N2 and 528 ℃ in air.

关键词： Ionic liquids Poly(ether-imide) Polycodensation Green media thermal properties.

EFFECT OF T-ZnOw DIMENSION ON properties.OF T-ZnOw/PA6 COMPOSITES

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Chinese Journal of Polymer Science 2009年第5期27卷 703-710页

作者：王勇 Key Laboratory of Advanced Technologies of Materials(Ministry of Education) School of Materials Science and EngineeringSouthwest Jiaotong University

As a part of serial work about the application of a tetra-needle-shaped whisker(T-ZnOw) with a spatial structure in polymer composites,this work is focused on the effect of T-ZnOw dimension on the properties.of polymer composites. Two kinds of T-ZnOw whiskers with different dimensions(big and small one) are introduced into PA6 *** results show that for the big whisker and the small whisker both,the addition of T-ZnOw induces the mechanical property improvement of T-ZnOw/PA6 ***,...

关键词： T-ZnOw/PA6 composites Dimension Mechanical properties thermal properties.

Study on the Novel Dicyanate Ester Resin Containing Naphthalene Unit

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Chinese Chemical Letters 2004年第9期15卷 1050-1052页

作者： HongQiangYAN HongYunPENCG LiJI GuoRongQI DepartmentofPolymerScienceandEngineering ZhejiangUniversityHangzhou310027

The novel dicyanate ester resin containing naphthalene unit (DNCY) was synthesized, and characterized by FT-IR, 1H-NMR, 13C-NMR and elemental analysis (EA). The thermal properties.of DNCY resin was studied by thermal degradation analysis at a heating rate of 10 C /min-1 in N2 and air. The DNCY resin exhibited better thermal and thermal-oxidative stability than bisphenol A dicyanate (BACY) resin.

关键词： Naphthalene unit dicyanate ester resin synthesis thermal properties.

Mechanical and physical characterization of sodium hydroxide treated Borassus fruit fibers

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Journal of Forestry Research 2012年第4期23卷 667-674页

作者： Obi Reddy K Shukla M Uma Maheswari C Varada Rajulu A Department of Mechanical Engineering Technology Doornfontein CampusP.O Box 17011University of JohannesburgJohannesburg 2028South Africa Department of Polymer Science and Technology Sri Krishnadevaraya UniversityAnantapur 515055India

In order to improve the properties.by chemical modification and to optimize the alkali concentration, we treated Borassus fruit fine fibers with aqueous sodium hydroxide solutions of different concentra- tions. In each case, the tensile properties.of the fibers were determined. The morphology of the untreated and alkali treated fibers was observed using scanning electron microscope. The surface of the fibers became rough on alkali treatment. The tensile properties.of the fibers improved on alkali treatment. The fibers attained maximum tensile properties.when treated with 15% aqueous sodium hydroxide solution and decreased thereafter. The crystallinity index of the fibers showed a similar trend. The thermal stability of the alkali treated fibers was found to be higher than that of untreated fibers. Further, the char content was maximum for fibers treated with alkali having concentration of 15% and above. The chemical composition indicated that the percentageof a-cellulose was maximum when the fibers were treated with 15% aqueous sodium hydroxide solution and then decreased thereafter thus indicating the beginning of degradation of the fibers at higher concentrations. Thus, the optimum concentration of NaOH was established as 15% for alkali treatment of the Borassus fibers.

关键词： borassus fruit fine fiber chemical composition mercerization spectral analysis tensile properties thermal properties.

thermal radiation heat transfer 4th ed.

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properties.of h-BN/Si3N4 Composite Ceramics Fabricated by Gel-Casting

2002年

作者： Siegel Robert 1927-

来源：畅想之星图书光盘版（南... 评论

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Properties of h-BN/Si3N4 Composite Ceramics Fabricated by Ge...

Three-dimensional thermo-mechanical finite element simulation for casting ladle structure under thermal loadings

中国材料大会2012

作者： Chang Liu Dechang Jia Shengjin Wang Wang Cui Institute for Advanced Ceramics Harbin Institute of TechnologyBuilding C3Science Park Harbin Institute of Technology

ISBN: (纸本)9783037856079

h-BN/Si3N4 composite ceramics were fabricated by gel-casting method and pressureless sintering using Si3N4 and h-BN as raw materials. The effect of h-BN on the microstructure and comprehensive properties.of h-BN/Si3N4 ceramic were investigated. The results showed that the introduction of h-BN hindered the densification of h-BN/Si3N4 ceramic as well as the transformation of α-Si3N4 to β-Si3N4 . The mechanical properties.of Si3N4 based ceramics decreased with the increase of h-BN content, while the thermal property, dielectric properties.and machinability increased.

关键词： Gel-casting h-BN/Si3N4 composite ceramics Mechanical properties Dielectric properties thermal properties.

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Three-dimensional thermo-mechanical finite element simulatio...