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Synthesis and evaluation of an oil-soluble viscosity reducer for heavy oil 被引量:27
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作者 Guo Jixiang Wang Heyi +2 位作者 Chen Chaogang Chen Yun Xie Xiaohai 《Petroleum Science》 SCIE CAS CSCD 2010年第4期536-540,共5页
To reduce the viscosity of highly-viscous oil of the Tahe oilfield (Xinjiang,China),an oilsoluble polybasic copolymer viscosity reducer for heavy oil was synthesized using the orthogonal method.The optimum reaction ... To reduce the viscosity of highly-viscous oil of the Tahe oilfield (Xinjiang,China),an oilsoluble polybasic copolymer viscosity reducer for heavy oil was synthesized using the orthogonal method.The optimum reaction conditions are obtained as follows:under the protection of nitrogen,a reaction time of 9 h,monomer mole ratio of reaction materials of 3:2:2 (The monomers are 2-propenoic acid,docosyl ester,maleic anhydride and styrene,respectively),initiator amount of 0.8% (mass percent of the sum of all the monomers) and reaction temperature of 80 oC.This synthesized viscosity reducer is more effective than commercial viscosity reducers.The rate of viscosity reduction reached 95.5% at 50 oC.Infrared spectra (IR) and interfacial tensions of heavy oil with and without viscosity reducer were investigated to understand the viscosity reduction mechanism.When viscosity reducer is added,the molecules of the viscosity reducer are inserted amongst the molecules of crude oil,altering the original intermolecular structure of crude oil and weakening its ability to form hydrogen bonds with hydroxyl or carboxyl groups,so the viscosity of crude oil is reduced.Field tests of the newly developed oil-soluble viscosity reducer was carried out in the Tahe Oilfield,and the results showed that 44.5% less light oil was needed to dilute the heavy oil to achieve the needed viscosity. 展开更多
关键词 oil-soluble viscosity reducer heavy oil SYNTHESIS EVALUATION
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Tribological behaviour of oil-soluble organo-molybdenum compound as lubricating additives 被引量:3
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作者 SHI Pei-jing XU Bin-shi +2 位作者 XU Yi QIAO Yu-lin LIU Qian 《中国有色金属学会会刊:英文版》 CSCD 2004年第z1期386-390,共5页
A four-ball machine was employed to investigate the tribological performances and the synergetic function of organo-molybdenum compounds (molybdenum dialkyl-dithiophosphate and molybdenum dithiophosphate, coded as MoD... A four-ball machine was employed to investigate the tribological performances and the synergetic function of organo-molybdenum compounds (molybdenum dialkyl-dithiophosphate and molybdenum dithiophosphate, coded as MoDDP and MoDTP, respectively) as additives in liquid paraffin. The morphologies of the worn surfaces and elemental distributions were observed and determined by means of scanning electron microscopy and energy dispersive spectrometry. The chemical states of some typical elements on the worn surface were analyzed on X-ray photoelectron spectroscope. The results show that MoDDP and MoDTP additives in liquid paraffin have excellent antiwear and friction-reduction properties, which are attributed to the reaction film composed of MoS2, FeS and MoO2, and the deposited film composed of phosphate on the worn surface. Moreover, these two additives have synergetic friction-reducing and antiwear effect, which is closely related to the chemical states of S on the worn surface. 展开更多
关键词 oil-soluble organo-molybdenum additive friction-reduction and antiwear behaviour TRIBOCHEMISTRY
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Isocyanate-terminated Polyethers Toughened Epoxy Resin:Chemical Modification,Thermal Properties,and Mechanical Strength
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作者 蔡浩鹏 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2007年第2期256-260,共5页
The toughening of the diglycidyl ether of bisphenol A epoxy resin with isocyanateterminated polyethers (ITPE) was investigated. The progress of the reaction and the structural changes during modification process wer... The toughening of the diglycidyl ether of bisphenol A epoxy resin with isocyanateterminated polyethers (ITPE) was investigated. The progress of the reaction and the structural changes during modification process were studied using FTIR spectroscopy. The studies support the proposition that TDI (tolylene diisocyanate) acts as a coupling agent between the epoxy and polyethers, forming a urethane linkage with the former and the latter, respectively. Me THPA-cured ER/ITPs blends were characterized using dynamic mechanical analysis (DMA) and thermogravimetric analysis (TGA). It is indicated the glass transition temperature (T) of systems was lower than the T of pure epoxy resin and overfull ITPE separated from the modified epoxy resin and formed another phase at an ITPE-content of more than 10wt%. The thermal stability was decreased by the introduction of ITPE. The impact strength and the flexural strength of the cured modifiedepoxy increased with increasing the ITPE content and a maximum plateau value of about 24.03 kJ/m^2 and 130.56 MPa was measured in 10wt% ITPE. From scanning electron microscopy (SEM) studies of the fractrue surfaces of ER/ITPE systems, the nature of the micromechanisms responsible for the increases in toughness of the systems was identified. 展开更多
关键词 isocyanate-terminated polyethers epoxy resin DMA SEM impact strength
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Synthesis of Arsamacrocyclic Polyethers
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作者 Xin You CHEN Guo Feng YU Wen Tian TAO (Department of Chemistry. Xiaogan Teachers College,Hubei 432100)(Department of Chemistry, Wuhan University,Wuhan 430072) 《Chinese Chemical Letters》 SCIE CAS CSCD 1999年第8期665-666,共2页
The synthesis of eight new arsamacrocyclic Polyethers was described. The structures of these compounds were characterized by elemental analysis, IR, H-1-NMR and MS.
关键词 macrocyclic compound arsamacrocyclic polyether SYNTHESIS
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Synthesis and Characterization of EO/PO Random Copolyethers
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作者 郭建国 苑仁旭 +3 位作者 何素芹 朱诚身 焦宇 江建明 《Journal of Donghua University(English Edition)》 EI CAS 2004年第5期60-64,共5页
Ethylene oxide(EO) and propylene oxide(PO) random copolyethers were synthesized by the sequential addition of the mixture of ethylene oxide and propylene oxide to propylene glycol (initiator) in the presence of potass... Ethylene oxide(EO) and propylene oxide(PO) random copolyethers were synthesized by the sequential addition of the mixture of ethylene oxide and propylene oxide to propylene glycol (initiator) in the presence of potassium hydroxide(KOH), and characterized with infrared spectrum(FTIR) and nuclear magnetism resonance(NMR). The effects of catalyst concentration, reaction temperature, charging rate and EO/PO mixture ratio on the polymerization reaction were investigated. It was revealed that the optimal reaction condition is the ratio of 2.5∶1 000(KOH mass vs. product mass), at 114.6℃ and pressure below 0.4 MPa. The residual KOH was neutralized by phosphoric acid(H 3PO 4). Then the crude copolyether was refined with adsorbents, and the refined copolyether, which contains less than 0.7 μg/ml K+, was obtained as colorless, viscous liquid. 展开更多
关键词 ethylene oxide propylene oxide polyethER propylene glycol
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Characterization and Synthesis through Fast Phase-Transfer of Oil-Soluble Double-Coordinated Tea-Polyphenols Arsenic
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作者 Wenfu Zhou Yahong Chen Lin Zhang 《Journal of Biosciences and Medicines》 2014年第5期34-41,共8页
Fast phase-transferring was adopted in ethanol solution at the condition of n (oil-soluble tea pol-yphenol): N (As3﹢) = 2:1, 4:1, 6:1, pH = 4.0, temperature 40&deg;C - 45&deg;C, action period of 15 h to compo... Fast phase-transferring was adopted in ethanol solution at the condition of n (oil-soluble tea pol-yphenol): N (As3﹢) = 2:1, 4:1, 6:1, pH = 4.0, temperature 40&deg;C - 45&deg;C, action period of 15 h to compose the target, of which the productivity was 59%, UV was 267.50, 218.00, 220.50 nm, FTIR was 6291, 34158.6, 2850.2, 1708.2;1457.3;1370.4, 1224.2, 1144.0, 760.5 cm﹣1, fluorescence value λmax = 257, 591.1, 593.7, 590.3, 591.0, 591.5, XRD λ/nm is 3.6974, 4.186, 12.0762, 15.4747, 1H-NMRδ = 0.782, 1.193, 1.483 - 1.586, 1.959 - 2.184, 2.479, 3.116, 3.970 - 3.981, 5.231 - 5.753, 6.537 - 7.300. Finally it was ascertained through XRD as double-coordinated polycrystal compound. 展开更多
关键词 oil-soluble Tea-Polyphenols (TP) ARSENIC Compound FAST PHASE-TRANSFER Synthesis Characterization
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Synthesis and Application of Oil-Soluble Red Dyes Derived from p-n-Alkyl Aniline
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作者 Yi-Fen Chiang Yu-Chou Chao 《Materials Sciences and Applications》 2014年第8期485-490,共6页
In this study, the azo red dyes derived from p-n-alkyl aniline by the introduction of different alkyl groups having high solubility in dodecane were synthesized. Results indicated that the elementary properties of red... In this study, the azo red dyes derived from p-n-alkyl aniline by the introduction of different alkyl groups having high solubility in dodecane were synthesized. Results indicated that the elementary properties of red oil inks were 1) non-polarity;2) low viscosity (<3.0 cps);3) specified surface tension (<30 mN/m);4) intensity of visible absorption covering 480 - 540 nm;5) hue close to standard red (CIE(x, y) = 0.67, 0.33). We can conclude that these azo red dyes are applicable for electrowetting displays. 展开更多
关键词 oil-soluble RED DYES DODECANE ELECTROWETTING Display
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骨形成肽1和聚多巴胺复合涂层修饰提高聚醚醚酮表面活性
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作者 秦敬杰 郭子歌 +3 位作者 李睿 马士卿 卢瑞杰 李梦君 《中国组织工程研究》 CAS 北大核心 2025年第16期3318-3325,共8页
背景:聚醚醚酮具有与人体皮质骨相近的弹性模量及良好的射线透射性、化学稳定性和生物相容性等优点,有望应用于口腔种植领域,然而其具有生物惰性,难以与周围组织形成骨结合,因此如何提高聚醚醚酮的表面活性是目前的主要问题。目的:分析... 背景:聚醚醚酮具有与人体皮质骨相近的弹性模量及良好的射线透射性、化学稳定性和生物相容性等优点,有望应用于口腔种植领域,然而其具有生物惰性,难以与周围组织形成骨结合,因此如何提高聚醚醚酮的表面活性是目前的主要问题。目的:分析聚醚醚酮表面骨形成肽1和聚多巴胺复合涂层的促成骨和成血管作用。方法:将聚醚醚酮片浸泡于多巴胺溶液中24 h,制备聚醚醚酮-聚多巴胺材料;将聚醚醚酮-聚多巴胺材料浸泡于骨形成肽1溶液中24 h,制备聚醚醚酮-聚多巴胺-骨形成肽1材料,表征材料的微观形貌、亲水性与元素组成。将骨髓间充质干细胞分别接种于聚醚醚酮、聚醚醚酮-聚多巴胺、聚醚醚酮-聚多巴胺-骨形成肽1材料表面,通过活死细胞染色和细胞骨架染色评估细胞活性与黏附状态,茜素红和骨钙素免疫荧光染色检测细胞成骨分化能力。将人脐静脉内皮细胞分别接种于3组材料表面,通过活死细胞染色和细胞骨架/血管内皮生长因子免疫荧光染色评估细胞活性及成血管水平。结果与结论:①扫描电镜下可见聚醚醚酮材料表面光滑,聚醚醚酮-聚多巴胺材料表面出现凹凸不平的沉积物,聚醚醚酮-聚多巴胺-骨形成肽1材料表面有小颗粒突起;接触角测试结果显示,聚醚醚酮-聚多巴胺-骨形成肽1材料的亲水性优于其他两种材料;X射线光电子能谱测试结果显示,骨形成肽1成功修饰于聚醚醚酮材料表面;②活死细胞染色和细胞骨架染色显示,相较于其他两种材料,聚醚醚酮-聚多巴胺-骨形成肽1材料可提高骨髓间充质干细胞的活性与黏附;茜素红和骨钙素免疫荧光染色显示,相较于其他两种材料,聚醚醚酮-聚多巴胺-骨形成肽1材料可促进骨髓间充质干细胞的成骨分化;③活死细胞染色和免疫荧光染色显示,相较于其他两种材料,聚醚醚酮-聚多巴胺-骨形成肽1材料可提高人脐静脉内皮细胞的活性与黏附及血管内皮生长因子蛋白的表达;④结果表明,骨形成肽1和聚多巴胺复合涂层可提高聚醚醚酮表面的促成骨和成血管活性。 展开更多
关键词 聚醚醚酮 表面改性 聚多巴胺 涂层 骨形成肽1 成骨分化 成血管
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Pyrolysis-Gas Chromatography/Mass Spectrometry for Microstructure and Pyrolysis Pathway of Polyester-Polyether Multiblock Copolymer
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作者 罗爱芹 叶玲 +2 位作者 傅若农 谢桂阳 王显伦 《Journal of Beijing Institute of Technology》 EI CAS 2001年第1期45-50,共6页
The composition and sequence distribution of monomeric units in polyester polyether multiblock copolymer were studied by pyrolysis? gas chromatography (PGC) and pyrolysis gas chromatography/mass spectrometry (PGC/M... The composition and sequence distribution of monomeric units in polyester polyether multiblock copolymer were studied by pyrolysis? gas chromatography (PGC) and pyrolysis gas chromatography/mass spectrometry (PGC/MS). PGC was applied to study the F t curve of the multiblock copolymer and PGC/MS was used to separate and identify the pyrolyzates. DTA experiment was used to study the decomposition temperature. The results show that the beginning point of elastomer’s decomposition was about 300?℃ and the decomposition temperature of most of the sample was 550?℃. Many pyrolyzates were produced because of the breaking of weak bonds in the sample. The possible microstructure was verified and the pyrolysis pathway of the copolymer was investigated. 展开更多
关键词 thermoplastic elastomer polyester polyether multiblock copolymer pyrolysis gas chromatography/mass spectrometry copolymer pyrolysis pathway MICROSTRUCTURE pyrolyzates
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聚醚醚酮与钛网材料在颅骨缺损后修补术中的应用价值
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作者 韩建波 《中外医药研究》 2025年第1期9-11,共3页
目的:分析聚醚醚酮与钛网材料在颅骨缺损后修补术中的应用价值。方法:选取2020年4月—2024年4月于常州市武进人民医院接受颅骨缺损后修补术治疗的患者60例为研究对象,采用抽签法分为对照组与观察组,每组30例。对照组采用钛网材料,观察... 目的:分析聚醚醚酮与钛网材料在颅骨缺损后修补术中的应用价值。方法:选取2020年4月—2024年4月于常州市武进人民医院接受颅骨缺损后修补术治疗的患者60例为研究对象,采用抽签法分为对照组与观察组,每组30例。对照组采用钛网材料,观察组采用聚醚醚酮材料。比较两组术后并发症发生率、临床手术指标、塑性满意度及材料生物相容性。结果:观察者术后并发症总发生率低于对照组(P=0.038)。两组住院时间、术中出血量、手术时间比较,无统计学差异(P>0.05);观察组住院费用高于对照组(P<0.001)。观察组塑性总满意度高于对照组(P=0.009)。观察组材料生物相容性优于对照组(P=0.023)。结论:颅骨缺损后修补术中,聚醚醚酮材料生物相容性更佳,患者的并发症发生率更低,塑性总满意度高,但钛网材料价格较低,需根据患者实际情况选取材料。 展开更多
关键词 聚醚醚酮 钛网 颅骨缺损后修补术
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双柔性链段自乳化环氧树脂固化剂的分子构建及涂层性能
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作者 费贵强 高腾腾 +3 位作者 陈光娣 陈阳芳 王丹丹 白阳 《精细化工》 北大核心 2025年第1期224-232,共9页
将双酚A型环氧树脂(E51)改性三乙烯四胺(TETA),同时引入含(不含)“树枝”状长碳链柔性链段的二聚酸(DA)及端环氧的聚醚链段柔性链段DEG501,经开环加成反应,制备了双(单)柔性链段固化剂〔DTED(TED)〕。采用TED、DTED分别对E51进行固化,... 将双酚A型环氧树脂(E51)改性三乙烯四胺(TETA),同时引入含(不含)“树枝”状长碳链柔性链段的二聚酸(DA)及端环氧的聚醚链段柔性链段DEG501,经开环加成反应,制备了双(单)柔性链段固化剂〔DTED(TED)〕。采用TED、DTED分别对E51进行固化,制备了单、双柔性链段环氧树脂(E51-TED、E51-DTED)。采用FTIR、1HNMR、GPC对样品进行了表征。考察了DA添加量对制备的E51-DTED形貌、热性能、力学性能、亲水性、耐盐雾性能、溶胀性能的影响。结果表明,由DA添加量8.4 g、TETA 29.2 g、E5133.3 g、DEG50112.8 g制备的DTED固化E51得到的E51-DTED 1#的玻璃化转变温度可达到123℃,质量损失10%的温度达到365℃,远大于E51-TED的72和342℃;随着DA添加量的增加,制备的E51-DTED抗压强度增强,拉伸强度和断裂伸长率减小,断裂压缩率先减小后增加,但均低于E51-TED的力学性能;随着DA添加量的增加,制备的E51-DTED耐水性增强,耐无水乙醇性减弱,疏水性和耐盐雾性能先增强后减弱。 展开更多
关键词 二聚酸 端环氧的聚醚链段柔性链段 双柔性链段 固化剂 环氧树脂 建筑用化学品
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打印密度对熔融沉积成型PEEK力学性能的影响
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作者 孙野 郭纯 黄光灿 《合成纤维》 2025年第2期72-76,共5页
聚醚醚酮是一种高性能聚合物,其优异的性能使其在工程塑料中处于领先地位。近年来,3D打印技术渐渐成熟,因为其节省材料、快速制造的特点被应用于许多领域。采用熔融沉积成型计算打印聚醚醚酮(PEEK),讨论了在打印温度为400℃、打印速度为... 聚醚醚酮是一种高性能聚合物,其优异的性能使其在工程塑料中处于领先地位。近年来,3D打印技术渐渐成熟,因为其节省材料、快速制造的特点被应用于许多领域。采用熔融沉积成型计算打印聚醚醚酮(PEEK),讨论了在打印温度为400℃、打印速度为50 mm/s、打印层高为0.2 mm参数下,打印密度为40%、50%、60%、70%时PEEK的拉伸和冲击性能,研究结果表明,50%打印密度下PEEK的力学性能最优。 展开更多
关键词 聚醚醚酮 熔融沉积 3D打印 力学性能
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填料对硅烷改性聚醚密封胶性能的影响研究
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作者 丁晓旭 薛雪雪 +2 位作者 周洪芝 魏莹 张超 《中国建筑防水》 2025年第1期24-28,34,共6页
探讨了填料在硅烷改性聚醚密封胶中的应用,重点分析了不同种类填料复配对密封胶力学性能和施工性能的影响。通过优化单一填料用量并进行复配试验,系统评估了各填料组合对密封胶整体性能的贡献。结果表明,合理选择填料及其配比能够显著... 探讨了填料在硅烷改性聚醚密封胶中的应用,重点分析了不同种类填料复配对密封胶力学性能和施工性能的影响。通过优化单一填料用量并进行复配试验,系统评估了各填料组合对密封胶整体性能的贡献。结果表明,合理选择填料及其配比能够显著改善密封胶的综合性能。 展开更多
关键词 硅烷改性聚醚密封胶 填料 纳米碳酸钙 气相二氧化硅 力学性能 施工性能
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Determination of Three Kinds of Polyether Drug Residues in Eggs by QuEChERS dSPE EMR-Lipid-LC/MS/MS 被引量:6
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作者 Guodong ZANG Jingwen FU +2 位作者 Qinzhan YANG Zijing HUANG Mengjun CHEN 《Agricultural Biotechnology》 CAS 2018年第1期120-122,共3页
[Objectives] This study was conducted to establish an LC-MS/MS method for the determination of three kinds of polyether residues in eggs with QuEChERS dSPE EMR-Lipid as a pretreatment method, which was established acc... [Objectives] This study was conducted to establish an LC-MS/MS method for the determination of three kinds of polyether residues in eggs with QuEChERS dSPE EMR-Lipid as a pretreatment method, which was established according to Agilent Bond Elut enhanced lipid removal EMR-Lipid technology. [ Methods] Egg was extracted by acidified acetonitrile, purified by Bond Elut EMR-Lipid QuEChERS, and detected by HPLC-MS/MS. [ Results] The three kinds of polyether residues had good linear relationships in the range of 2.0 - 100 μg/L with peak areas, r 〉 0. 999. The recoveries ranged from 84.6% to 107.0%. [ Conclusions ] The method is convenient and accurate, and the quantitative results are accurate and reproducible. It is suitable for the determination of the three kinds of polyether residues in eggs. 展开更多
关键词 QUECHERS EMR-Lipid Liquid phase tandem mass spectrometry polyethers
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Hydrogenation of SBS Catalyzed by Immobilized Ru-TPPTS Complex in Polyether Molten Salt 被引量:1
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作者 LiWEI JingYangJIANG YanHuaWANG ZiLinJIN 《Chinese Chemical Letters》 SCIE CAS CSCD 2005年第3期338-340,共3页
Catalytic hydrogenation of SBS was performed for the first time in polyether molten salt with Ru/TPPTS complex as catalyst. Experimental results showed that the hydrogenation degree can be enhanced significantly by th... Catalytic hydrogenation of SBS was performed for the first time in polyether molten salt with Ru/TPPTS complex as catalyst. Experimental results showed that the hydrogenation degree can be enhanced significantly by the addition of triphenylphosphine (TPP). When the molar ratio of TPP, TPPTS and Ru is 2:5:1, 89% hydrogenation degree can be achieved after 12 h under reaction conditions of 5.0 MPa and 150°C. The ionic liquid containing catalyst can be reused three times without obvious changes in the catalytic selectivity and activity. 展开更多
关键词 HYDROGENATION SBS ruthenium complex polyether molten salt.
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Novel Silica Gel Supported Polyether Ionic Liquids: Efficient Catalysts Applied in Transformation of Carbon Dioxide 被引量:1
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作者 Guo Liying Jin Xianchao +1 位作者 Wang Yirong Wang Haozhi 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2018年第4期60-66,共7页
Three new catalysts based on the silica gel supported polyether ionic liquids(ILs), i.e., [HO-PECH-MIM]ClSi, [H2N-PECH-MIM]Cl-Si, and [HOOC-PECH-MIM]Cl-Si, were prepared, and their chemical structures were characteriz... Three new catalysts based on the silica gel supported polyether ionic liquids(ILs), i.e., [HO-PECH-MIM]ClSi, [H2N-PECH-MIM]Cl-Si, and [HOOC-PECH-MIM]Cl-Si, were prepared, and their chemical structures were characterized by infrared(IR) spectroscopy and nuclear magnetic resonance(NMR) spectroscopy. Thermogravimetric analyzer(TG), X-ray diffractometer(XRD) and scanning electron microscope(SEM) were used to evaluate their thermal stability,crystalline structure and apparent morphology, respectively. Surface areas of the prepared catalysts were calculated by the Brunauer-Emmett-Teller(BET) method. The catalytic reaction for the synthesis of propylene carbonate(PC) using CO_2 and propylene oxide(PO) in the presence of the prepared catalysts was studied. The influences of times of recycling and catalyst structure on catalytic performance were also investigated. The experimental results showed that the silica gel supported polyether ILs catalysts successfully prepared under mild condition could possess the advantages of high activity, excellent thermal stability, good selectivity and easy recycling, while the phase transition of the liquid polyether ILs catalysts was also achieved. When the reaction temperature was 90 °C, the CO_2 pressure was 2.0 MPa and the dosage of the catalyst was 2.5%, [HOOC-PECH-MIM]Cl-Si was found to have the best catalytic performance in the catalytic process, with the conversion rate reaching 100% and the selectivity equating to 98.2%. The conversion rate and selectivity still could reach more than 90% even after the catalyst was reused for 15 times. 展开更多
关键词 .polyether IONIC liquids SILICA GEL catalyst CO2
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Proton Conducting Composite Membranes from Sulfonated Polyether Ether Ketone and SiO_2 被引量:1
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作者 张高文 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2009年第1期95-99,共5页
Proton conducting composite membranes from sulfonated polyether ether ketone and SiO2 for direct methanol fuel cell (DMFC) application were prepared with sulfonated polyether ether ketone(SPEEK) and tetracethoxy s... Proton conducting composite membranes from sulfonated polyether ether ketone and SiO2 for direct methanol fuel cell (DMFC) application were prepared with sulfonated polyether ether ketone(SPEEK) and tetracethoxy silane(TEOS) by sol-gel method. The covalent crosslinking structure was formed between —SO3H of SPEEK via SiO2. The SEM images show that the interfacial compatibility of SPEEK and SiO2 is improved obviously and SiO2 disperses uniformly in the polymer matrix and the particle diameter of SiO2 does not exceed 40 nm. The proton conductivity of composite membranes decreases slightly compared with the SPEEK membrane while the methanol permeability and swelling of composite membrane are improved remarkablely owing to covalent cross-linking between —SO3H and SiO2 . 展开更多
关键词 direct methanol fuel cell sulfonated polyether ether ketone sol-gel method proton conductivity methanol permeability
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A Structure-properties Study of MDI-based Hydrophilic Polyether-polyester Polyurethane 被引量:1
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作者 权衡 顾振亚 吴穗生 《Journal of Donghua University(English Edition)》 EI CAS 2009年第4期408-412,共5页
A series of segmented polyether-polyester polyurethane with amorphous hydrophilic soft segment domains were prepared from 4,4'- diphenylmethane diisocyanate (MDI), polybutylene adipate (Glycol) 2000 (PBA2000), and... A series of segmented polyether-polyester polyurethane with amorphous hydrophilic soft segment domains were prepared from 4,4'- diphenylmethane diisocyanate (MDI), polybutylene adipate (Glycol) 2000 (PBA2000), and polyethylene glycol 1000 (PEG1000), with 1,4-butanediol (BDO) as the chain extender. Furthermore, several representative properties of the polyurethanes, such as moisture permeability, water resistance, hydrophilic property, and phase inversion temperature, were investigated. The studies show that the structure and concentration of soft segment have a remarkable effect on the main application properties of polyurethane. On the contrary, the functional properties of the polyurethane are almost not affected by its hard segment. 展开更多
关键词 hydrophilic polyurethane polyethER polyester structure property
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SYNTHESIS AND CHARACTERIZATION OF A FLAME RETARDANT HYPERBRANCHED POLYETHER
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作者 Jyotishmoy Borah 汪传生 Niranjan Karak 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2010年第1期107-118,共12页
A brominated hyperbranched polyether has been synthesized from cyanuric chloride and sodium salt of tetrabromobisphenol-A by an A2 + B3 approach. The synthesized polyether was characterized by ^1H-NMR, ^13C-NMR, UV, ... A brominated hyperbranched polyether has been synthesized from cyanuric chloride and sodium salt of tetrabromobisphenol-A by an A2 + B3 approach. The synthesized polyether was characterized by ^1H-NMR, ^13C-NMR, UV, FTIR spectroscopy and X-ray diffraction studies, measurements of solution viscosity, molecular weight and solubility and elemental and thermogravimetric analyses. The flame retardancy of the synthesized polyether and its blends with commercially available plasticized poly(vinyl chloride) (PVC) and low density polyethylene (LDPE) was investigated by measurements of limiting oxygen index (LOI) value and thermogravimetric analysis. The properties are compared with a non-halogenated similar type of bisphenol-A based aromatic polyether after blending at different dose levels with the same base polymers. The LOI values of these blends indicated that these hyperbranched polyethers acted as flame retardant additives, and antimony trioxide had prominent synergistic effect with the bromo hyperbranched polyether for the above base polymers, and an increment of 4 to 6 units in LOI values was observed. 展开更多
关键词 Hyperbranched polyether LOI LDPE PVC.
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Alkylation of Isobutane and Isobutene in Acidic Polyether Ionic Liquids 被引量:2
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作者 Yu Fengli Gu Yulong +1 位作者 Liu Qichun Xie Congxia 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2019年第3期29-35,共7页
The Br?nsted-acidic polyether ionic liquids(ILs)with different polymerization degrees(n value)were prepared via the reaction of tetramethylguanidine and epoxy ethane,followed by successive reactions with 1,3-propane s... The Br?nsted-acidic polyether ionic liquids(ILs)with different polymerization degrees(n value)were prepared via the reaction of tetramethylguanidine and epoxy ethane,followed by successive reactions with 1,3-propane sultone and trifluoromethanesulfonic acid(TfOH).The prepared ILs were characterized by infrared spectroscopy and 1H nuclear magnetic resonance spectroscopy,and their thermal stability was determined by thermal gravimetry.The synthesized polyether ILs coupled with TfOH were used to catalyze the alkylation reaction of isobutane and isobutene for the preparation of alkylate gasoline.The polyether ILs could improve the substrate dissolution and promote the separation of the catalyst from the products.The ideal IL(n=94)was determined.The optimized alkylation reaction conditions covered:a VTfOH/VIL ratio of 0.35,a reaction temperature of 40℃,a reaction time of 50 min,and a stirring speed of 800 r/min.The conversion of isobutene was 92.4%and the selectivity for the C8-product was 81.6%.Under optimal conditions,the catalyst life was determined and TfOH showed improved cyclic performance in the polyether ILs.After 8 operating cycles,the catalytic activity of the catalyst showed negligible decline. 展开更多
关键词 ALKYLATION ALKYLATE gasoline tri fluoromethanesulfonic acid polyether-based ionic liquid ISOBUTENE
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