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相同软硬段质量配比聚醚酯弹性体PEG/PBT的结构与表征 总被引:9,自引:0,他引:9
以熔融缩聚法合成了一系列聚乙二醇(PEG)/聚对苯二甲酸丁二醇酯(PBT)聚醚酯热塑性弹性体,用NMR,FTIR,DSC及力学性能测试等方法表征了材料的结构及性能.讨论了在相同软硬段质量配比下,不同软硬段长度对材料性能的影响.结果表明,随着软段PEG长度增加,硬段PBT长度相应增长,弹性模量基本保持不变,抗拉强度、屈服应力及特性粘度增加. 相似文献
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聚醚酯嵌段共聚物熔体的流变性能 总被引:11,自引:1,他引:10
采用毛细管流变仪测定了组成比、聚醚分子量、熔融时间和熔融温度对嵌段聚醚酯熔体表观粘度的影响.结果发现在所研究的温度和切变速率范围内,该结构聚醚酯熔体为假塑性非牛顿流体,其粘度随聚酯段含量的增加而增加,随熔融时间增加而降低,随聚醚分子量的增大而增大.聚醚酯的零切粘度可由Spencer Dillon 公式外推得到,零切粘度对温度的依赖关系服从Andrade 公式. 相似文献
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聚醚中聚合物分散粒子的形态对体系稳定性和粘度的影响 总被引:1,自引:1,他引:1
以苯乙烯和丙烯腈在聚醚中的分散聚合制备了聚合物聚醚,用电镜观察了不同合成条件下分散粒子的形态轨现工艺因素可改变分散粒子的形态,从而影响POP的性质。颗粒聚集是影响体系稳定性和粘度的主要因素。在适宜的合成条件下,可获得稳定的表面光滑的孤立圆球,相应的POP具有低的粘度。 相似文献
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用Instron3211型毛细管流变仪研究了以对羟枯苯甲酸、对苯二甲酯和双酚为单体合成的共聚芳酯液晶熔体的流变性能。结果表明,切变速率、熔体温度及PHB链节含量对切粘度和结构粘度有很大的影响。 相似文献
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Shan Yang Zhiqing Zhang Fang Wang Lijuan Feng Xiaoxia Jiang Chuntian Yang Xianhong Jiang Guoqiang Liu 《Polymer Science Series A》2014,56(6):917-927
Several kinds of highly-branched block polyethers were synthesized via anion ring-opening polymerization of propylene oxide (PO) and ethylene oxide (EO), using phenol-amine resin (PA) as the initiator. The rheological properties determined by rotational rheometer all followed the regular rules of polymer systems: under a certain conditions, the bulk polyethers were pseudoplastic and non-Newtonian fluid, and with the increasing of the shear rate and temperature, the apparent viscosity of the block copolymers were reduced. In addition, modulus determination showed that such polyether molecules presented preferable viscosity compared to the elasticity, meanwhile, storage modulus, loss modulus and compound viscosity all decreased with the increasing of temperature. Storage modulus and loss modulus increased along with the scanning frequency increasing. But compared with the same kind of linear polymers, the significant difference was the low melt viscosity, which attributed to the special three-dimension space structure hindering the entanglement of chains. Furthermore, the rheological properties among the several block polyethers showed differences obviously. In other words, the number of block and the content of EO all have a significant effect on the rheological properties, specifically, the modulus will increase with the increasing of the block number and the EO content. 相似文献
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甲基丙烯酸与聚乙二醇进行单酯化反应后,与三溴化磷进行溴化反应,合成了溴代单甲基丙烯酸聚乙二醇酯(B rPEG-MMA)。优化了溴化反应条件,并依靠红外光谱及化学分析手段,证实了目标产物的结构;并且测定了产物粘度在不同温度下的变化状况。 相似文献
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A novel phosphonic acid containing bisphenol was successfully synthesized from phenolphthalein and m-aminophenylphosphonic acid. Poly(arylene ether)s containing phosphonic acid groups were prepared from the bisphenol. This is the first report on the attachment of phenylphosphonic acid groups as side chains to aromatic polyethers. These polyethers had very high glass transition temperatures and molecular weights. The conductivities of the polyethers ranged from 10−5 to 10−6 S cm−1 and therefore show promise as proton-exchange polymer electrolyte membranes for fuel cells. 相似文献
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3,4‐Ethylenedioxythiophene Functionalizationed with Tetrathiafulvalene: Synthesis and Selective Esterification 下载免费PDF全文
Lei Zhang Changzhi Wu Chengyun Wang Hujin Zuo Yongjia Shen 《Journal of heterocyclic chemistry》2014,51(5):1277-1281
3,4‐(Hydroxymethyl‐ethylenedioxy)thiophene ( 4 ) and 3,4‐(2′‐hydroxypropylenedioxy)thiophene ( 4' ′) were synthesized from dimethyl 3,4‐dihydroxythiophene‐2,5‐dicarboxylate ( 1 ), which were isomers and difficult to separate. When they were esterified with tetrathiafulvalene carried carboxylic acid group, only 3,4‐(hydroxymethyl‐ethylenedioxy)thiophene ( 4 ) could be esterified. No such selectivity was observed when the isomers were esterified by lauric acid and benzoic acid, respectively. 相似文献
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Yasuo Saegusa Takeshi Iwasaki Shigeo Nakamura 《Journal of polymer science. Part A, Polymer chemistry》1994,32(2):249-256
Seven 1,3,4-thiadiazole-containing polyethers with reduced viscosities of 0.27–1.44 dL/g were synthesized by the high-temperature solution polycondensation of novel activated difluoride, 2,5-bis (4-fluorophenyl)-1,3,4-thiadiazole, with aromatic diols possessing a variety of ring structures. The expected chemical structures were confirmed by IR and 1H-NMR spectroscopy and elemental analysis. Of all the polymers, three polyethers were highly crystalline and soluble only in limited solvents such as concentrated sulfuric acid. The other polyethers were amorphous and dissolved easily in a variety of organic solvents including N-methyl-2-pyrrolidone (NMP), phenols, and chlorinated hydrocarbons. Colorless to slightly yellow-colored, transparent, and tough films could be cast from the NMP solutions of the amorphous polyethers. The mechanical properties of the films were excellent, and their tensile strength, elongation at break, and tensile moduli were in the ranges of 48–72 MPa, 5–7%, and 1.3–1.9 GPa, respectively. The amorphous polyethers had high glass transition temperatures of 204–299°C. All the polyethers were highly thermally and thermooxidatively stable and exhibited no weight loss up to 400°C, with 10% weight loss being recorded at 464–513°C in air. © 1994 John Wiley & Sons, Inc. 相似文献
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Kazuhisa Hiratani Hideki Sugihara Kazuhiro Taguchi 《Journal of inclusion phenomena and macrocyclic chemistry》1984,2(1-2):161-169
Several noncyclic polyether compounds containing oxytrimethylene groups and o-carboxyphenyl terminal group were synthesized. It has been found that they can transport lithium ion selectively in the competitive alkali metal ion transport through liquid membranes. The results of the spectroscopic study, together with inspection on the basis of the CPK model building suggest that these polyethers can form a pseudocavity, in which lithium ion best fits, and then the terminal aromatic rings overlap one another face-to-face to form a stacking structure. By using newly synthesized polyethers, which were designed on the basis of the conformational information, the significant contribution of the structures of these polyethers could be verified. 相似文献
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The near infrared reflectance spectra of the skin of atopic and normal subjects were compared after topical application of perfluorinated polyethers (fomblins) of different molecular weight and viscosity. It was possible to distinguish the two classes of subjects and the different fomblins applied, by principal components analysis. 相似文献
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本文报道一类新型大环聚醚的合成.在以1,7-二氧杂-4,10-二氮杂环十二烷(1a)及1,7,10,16-四氧杂-4,13-二氮杂环十八烷(1b)中的两个仲胺上进行含醚键的卤代烷取代反应,获得一批带有两个含有侧链醚键的新型冠醚.以碳酸钾为缩合剂,所得冠醚碱金属配合物经酸分解及四甲基氢氧化铵处理后,得游离的大环聚醚. 用溶解度法初步测定了这类冠醚对碱金属的配位性能.结果指出,其母环及侧链上氧原子数的多少及碱金属离子半径的大小均影响配合物的稳定性,其中有些冠醚对碱金属有良好的配位能力,有的还具有优异的选择性,例如N,N′-β-甲氧基乙基-1,7-二氧杂-4,10-二氮杂环十二烷(13a)对钾及钠离子的选择比大于18-c-β,并比4,4′(5′)-二甲基苯并-30-c-10还高. 相似文献
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Houjian Gong Guiying Xu Teng Liu Jinyu Pang Wenling Dou Xia Xin 《Colloid and polymer science》2011,289(8):933-942
The block polyethers with different structure and composition were synthesized by anionic polymerization and used to disperse single-walled carbon nanotubes (SWNTs). The block polyethers with the structure of branch or benzene ring had better dispersion ability than the commercial Pluronic block polyethers (L64 and F127). In order to compare the parameters, dispersion limit and efficiency of polyethers for SWNTs were defined. UV?Cvis?Cnear infrared absorbance spectra showed that eight-branch polyether AE82 had much larger dispersion limit and efficiency than five-branch AE52. BPE containing benzene rings in the molecule had a slightly lower dispersion limit but larger dispersion efficiency than AE82. The defect density of SWNTs dispersed in polyether aqueous solutions was investigated by Raman spectroscopy. The polyethers AE83 and BEP with the structure of poly(ethylene oxide)?Cpoly(propylene oxide) dispersed less defective SWNTs than AE82 and BPE, indicating that the variation of polyether structure and composition could influence the defect density of SWNTs besides dispersion limit and efficiency. 相似文献