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Synthesis of Poly(butylene terephthalate)-Poly(tetramethylene glycol) Copolymers Using Terephthalic Acid as Starting Material: A Comparation between Two Synthetic Strategies

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Chinese Journal of Polymer Science 2015年第9期33卷 1283-1293页

作者： Jun-wu Zhang Fei Liu jing-gang wang 那海宁朱锦 Ningbo Key Laboratory of Polymer Materials Ningbo Institute of Materials Technology and EngineeringChinese Academy of Sciences

Poly（butylene terephthalate）-poly（tetramethylene glycol）（PBT-PTMG） copolymer is prepared with terephthalic acid （PTA） rather than its dimethyl ester （DMT） as starting material by a two-step melt polycondensation. This process includes the synthesis of PBT prepolymer from PTA with 1,4-butanediol （BDO） in the first step, followed by the synthesis of PBT-PTMG copolymer from PBT prepolymer with PTMG in the second step. The molecular weight, composition as well as thermal and mechanical properties of the products from the two-step melt polycondensation are compared with the properties of the PBT-PTMG from the traditional one-step melt polycondensation. When the PTMG content is low, there is only slight difference in molecular weight, composition, thermal and mechanical properties among PBT-PTMG copolymers obtained from these two methods. However, when the PTMG content is high, only the two-step strategy is able to give high molecular weight products, and the products have comparable thermal and mechanical properties with those from traditional one-step strategy using DMT as starting material.

关键词： Polycondensation Elastomer Poly(ether-esters).

Improvement in Toughness of Poly(ethylene 2,5-furandicarboxylate) by Melt Blending with Bio-based Polyamide11 in the Presence of a Reactive Compatibilizer

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Chinese Journal of Polymer Science 2020年第10期38卷 1099-1106页

作者： Yong Yang An-Ping Tian Ya-Jin Fang jing-gang wang Jin Zhu Key Laboratory of Bio-based Polymeric Materials Technology and Application of Zhejiang Province Ningbo Institute of Materials Technology and EngineeringChinese Academy of Sciences Weihai Honglin Electronic Technology CO. LTD

The objective of this study was to improve the toughness of bio-based brittle poly(ethylene 2,5-furandicarboxylate)(PEF) by melt blending with bio-based polyamide11(PA11) in the presence of a reactive multifunctional epoxy compatibilizer(Joncryl ADR?-4368).The morphological,thermal,rheological,and mechanical properties of PEF/PA1 1 blends were *** with neat PEF,the toughness of PEF/PA11 blend was not improved in the absence of the reactive compatibilizer due to the poor compatibility between the two *** Joncryl was incorporated into PEF/PA1 1 blends,the interfacial tension between PEF and PA1 1 was obviously reduced,reflecting in the fine average particle size and narrow distribution of PA11 dispersed phase as observed by scanning electron microscopy(SEM).The complex viscosities of PEF/PA11 blends with Joncryl were much higher than that of PEF/PA11 blend,which could be ascribed to the formation of graft copolymers through the epoxy groups of Joncryl reacting with the end groups of PEF and PA11 molecular ***,the compatibility and interfacial adhesion between PEF and PA11 were greatly improved in the presence of *** compatibilized PEF/PA11 blend with 1.5 phr Joncryl exhibited significantly improved elongation at break and unnotch impact strength with values of 90.1% and 30.3 kJ/m2,respectively,compared with those of 3.6% and 3.8 kJ/m2for neat PEF,*** work provides an effective approach to improve the toughness of PEF which may expand its widespread application in packaging.

关键词： Poly(ethylene 2,5-furandicarboxylate) Polyamide11 Bio-based polymers Reactive compatibilization Toughening

FLEXURAL VIBRATIONS BAND GAPS IN PERIODIC BEAMS INCLUDING ROTARY INERTIA AND SHEAR DEFORMATION EFFECTS

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Chinese Journal of Mechanical Engineering 2006年第1期19卷 25-27页

作者： YU Dianlong WEN Jihong LIU Yaozong QIU jing wang gang College of Mechantronics Engineering and Automation National University of Defense Technology Changsha 410073 China

With the idea of the phononic crystals, the beams with periodic structure are designed. Flexural vibration through such periodic beams composed of two kinds of materials is studied. The emphasis is laid on the effects of rotary inertia and shear deformation. Based on the vibration equation, plane wave expansion method is provided. The acceleration frequency responses of such beams with finite structure are simulated by the finite element method. The frequency ranges of sharp drops in the calculated acceleration frequency response curves are in good agreement with those in the band structures. The findings will be significant in the application of the periodic beams.

关键词： Phononic crystals Band gaps Rotary inertia Shear delormation

Synthesis and Properties Investigation of Thiophene-aromatic Polyesters: Potential Alternatives for the 2,5-Furandicarboxylic Acid-based Ones

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Chinese Journal of Polymer Science 2020年第10期38卷 1082-1091,I0005页

作者： jing gang wang Xiao-Qin Zhang Ang Shen Jin Zhu Ping An Song Hao wang Xiao Qing Liu Ningbo Institute of Materials Technology and Engineering Chinese Academy of SciencesNingbo 315201China Universty of Chinese Academy ofSciences Bejing 100049China University of Southern Queensland SpringfieldQLD 4300Australia

In order to explore new substitutes for 2,5 furandicarboxylic acid(FDCA)or poly(ethylene 2,5 furandicarboxylate)(PEF)and try to develop more ideal bio based polyesters,several thiophene aromatic polyesters(PETH,PPTH,PBTH,and PHTH)were synthesized from dimethyl thiophene 2,5-dicarboxylate(DMTD)and different diols,including ethylene glycol,1,3-propanediol,1,4-butanediol,and 1,*** chemical structures of obtained polyesters were confirmed by nuclear magnetic resonance spectroscopy(H-NMR and 1'C-NMR).Determined by GPC measurement,their average molecular weight(M.)varied from 5.22 x 10*g/mol to 7.94 x 10*g/mol with the molar-mass dispersity of *** on the DSC and TGA results,the synthesized polyesters PETH,PPTH,and PBTH displayed comparable or even better thermal properties when compared with their FDCA-based *** PETH to PHTH,their Tg varied from 64.6°Cto-1°C while Tsm ranged from 409 C to 380°C in nitrogen atmosphere,PETH showed elongation at break as high as 378%,tensile strength of 67 MPa,and tensile modulus of 1800 ***,the CO2 and O2 barrier of PETH was 12.0 and 6.6 folds higher than those of PET,respectively,and similar to those of *** the overall properties,the synthesized thiophene aromatic polyesters,especially PETH,showed great potential to be used as an excellent bio based packaging material in the future.

关键词： 2,5-Thiophenedicarboxlic acid(TDCA) 2,5 Furandicarborxylic acid(FDCA) Bio based polyesters Brrier properties

Improvement in Toughness of Poly(ethyiene 2,5-furandicarboxyiate) by Melt Blending with Bio-based Polyamidel 1 in the Presence of a Reactive Compatibilizer

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Chinese Journal of Polymer Science 2020年第10期38卷 1099-1106,I0006页

作者： Yong Yang An-Ping Tian Ya-Jin Fang jing-gang wang Jin Zhu Key Laboratory of Bio based Polymeric Materials Technology and Application of Zhejiang Province Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201China Weihai Honglin Electronic TechnologyCO LTDWeihai 264205 China

The objective of this study was to improve the toughness of bio based brittle poly(ethylene 2,5-furandicarboxylate)(PEF)by melt blending with bio based polyamide11(PA11)in the presence of a reactive multifunctional epoxy compatibilizer(Joncryl ADR-4368).The morphological,thermal,rheological,and mechanical properties of PEF/PA11 blends were *** with neat PEF,the toughness of PEF/PA11 blend was not improved in the absence of the reactive compatibilizer due to the poor compatibility between the two *** Joncryl was incorporated into PEF/PA11 blends,the interfacial tension between PEF and PA11 was obviously reduced,reflecting in the fine average particle size and narrow distribution of PA11 dispersed phase as observed by scanning electron microscopy(SEM).The complex viscosities of PEF/PA11 blends with Joncryl were much higher than that of PEF/PA11 blend,which could be ascribed to the formation of graft copolymers through the epoxy groups of Joncryl reacting with the end groups of PEF and PA11 molecular ***,the compatibility and interfacial adhesion between PEF and PA11 were greatly improved in the presence of *** compatibilized PEF/PA11 blend with 1.5 phr Joncryl exhibited significantly improved elongation at break and unnotch impact strength with values of 90.1%and 30.3kJ/m2,respectively,compared with those of 3.6%and 3.8 kJ/m2 for neat PEF,*** work provides an effective approach to improve the toughness of PEF which may expand its widespread application in packaging.

关键词： Poly(ethylene 2.5-furandicarboxylate) Polyamide11 Bio based polymers Reactive compatibilization Toughening

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燃料组件内精细功率重构方法研究

原子能科学技术 2017年第1期51卷 95-99页

作者：管宇姚建凡李伟厉井钢陈俊王军令上海交通大学上海200240 中广核研究院有限公司广东深圳518026

为提高堆芯工程设计软件的计算精度,本文提出一种精细功率重构方法,即利用节块法求解所获得的横向积分中子通量分布作为逼近条件,采用权重系数法获得组件功率分布的两群17项多项式展开,并基于B&W和IAEA2D基准题与13项和21项多项式展开... 详细信息

为提高堆芯工程设计软件的计算精度,本文提出一种精细功率重构方法,即利用节块法求解所获得的横向积分中子通量分布作为逼近条件,采用权重系数法获得组件功率分布的两群17项多项式展开,并基于B&W和IAEA2D基准题与13项和21项多项式展开法进行比较。数值计算结果表明,提出的17项多项式展开法相比传统的13项多项式展开法具有更高的计算精度,且计算精度接近21项多项式展开法。

关键词：棒功率重构权重系数法横向积分通量

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认知功能障碍患者病前智力评价

中国现代神经疾病杂志 2016年第9期16卷 636-639页

作者：邹扬陈美蓉任汝静王刚上海交通大学医学院附属瑞金医院神经科上海交通大学医学院神经病学研究所200025 上海市普陀区人民医院神经内科 200060

神经心理学测验是痴呆和认知功能障碍诊断的重要依据。不同个体健康状态下基础认知水平不同,故发病后不应采用相同的评价标准来判断神经心理学测验结果。病前智力评价是修正此类误差的有效方法,但临床对该领域的重视程度仍较低,本文对... 详细信息

神经心理学测验是痴呆和认知功能障碍诊断的重要依据。不同个体健康状态下基础认知水平不同,故发病后不应采用相同的评价标准来判断神经心理学测验结果。病前智力评价是修正此类误差的有效方法,但临床对该领域的重视程度仍较低,本文对国内外病前智力评价方法及其在认知功能障碍中的应用进行综述。

关键词：认知障碍智力测验神经心理学测验综述

土优塔化学打顶剂对新疆棉花农艺性状及经济特性的影响

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南方农业学报 2017年第6期48卷 991-996页

作者：陈兵王静王刚张国蕾张素宣李小刚李宪和新疆农垦科学院新疆石河子832000 新疆石河子职业技术学院水利建筑工程分院新疆石河子832003 新疆生产建设兵团第十师184团新疆和布克赛尔蒙古834609

【目的】研究土优塔棉花打顶剂对棉花农艺性状、产量及纤维品质的影响,为化学打顶技术在新疆特早熟棉区的推广和应用提供科学依据。【方法】以新疆建设兵团第十师184团主栽棉花品种金垦5-6和新陆早62号为研究对象,以人工打顶为对照,于20... 详细信息

【目的】研究土优塔棉花打顶剂对棉花农艺性状、产量及纤维品质的影响,为化学打顶技术在新疆特早熟棉区的推广和应用提供科学依据。【方法】以新疆建设兵团第十师184团主栽棉花品种金垦5-6和新陆早62号为研究对象,以人工打顶为对照,于2013~2014年开展不同打顶时间(2013年为7月5日和7月15日,2014年为7月10和7月20日)、不同浓度(450、600、750、900和1050 mL/ha)土优塔打顶剂的棉花打顶对比试验,测定不同处理的棉花农艺性状、产量及品质性状等指标,并对各指标进行对比分析。【结果】喷施土优塔打顶剂后,棉株顶心内缩,停止生长,可在一定程度上抑制株高继续增长;多数化学打顶处理棉株叶龄数、果枝数和单铃重较对照增加,单铃数有增有减,衣分略微降低,籽棉产量和皮棉产量均有增有减。其中低浓度(450和600 mL/ha)土优塔打顶剂处理与对照相比,叶龄数增加2.00~4.00个,果枝数增加2.00~4.00台;2013年籽棉产量增加332~1014 kg/ha,皮棉产量增加124~377 kg/ha。品质分析结果表明,喷施打顶剂对棉花绒长影响较明显,对马克隆值、比强度、整齐度、伸长率、短纤维指数、成熟系数和纺织参数等品质指标影响不明显。【结论】低浓度(450和600 mL/ha)土优塔打顶剂处理对棉花的打顶效果较好,且对棉花品质基本无影响,可在新疆特早熟棉区推广应用。

关键词：棉花化学打顶农艺参数产量纤维品质新疆

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