共查询到19条相似文献,搜索用时 62 毫秒
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如何通过高效、廉价的方法制备2,5–呋喃二甲酸(2,5-FDCA)及其聚合物已成为近几年的研究热点。重点介绍了2,5-FDCA的合成路线、聚2,5–呋喃二甲酸乙二醇酯(PEF)及其共聚酯的研究进展,并对其进行了分析。分析结果表明,目前2,5-FDCA的合成以5–羟甲基糠醛(HMF)氧化路线为主,其中催化剂采用贵金属,价格比较昂贵,建议对高效低价的新型催化剂体系进行开发。另外,为提高材料的各种性能,研究FDCA基聚酯改性的高性能产品,对经济、社会发展有着重大应用价值。 相似文献
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以氯化亚铁为催化剂,呋喃、四氯化碳和甲醇回流反应10 h合成了呋喃-2,5-二甲酸二甲酯,产率97.5%;呋喃-2,5-二甲酸二甲酯经碱性条件下水解、酸化合成了呋喃-2,5-二甲酸,总产率90.7%。 相似文献
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2,5-呋喃二甲酸(FDCA)是合成新型可降解高分子聚酯(PEF)的主要单体.介绍了FDCA的主要性能及用途,重点介绍了FDCA的合成技术路线,根据合成原料及路线的不同,可以分为5-羟甲基糠醛(HMF)为原料(化学法)、糠酸糠醛为原料、己糖二酸为原料、二甘醇酸为原料、HMF为原料(生物法)共5种技术路线.分析结果表明:以糖为原料,HMF路线是2,5-FDCA工业化量产最有前景的路线,2,5-呋喃二甲酸合成的主要技术难点在于糖的高效选择性脱水反应与脱水过程中有效并有经济价值的氧化技术,选择高性能的催化剂及相对应的溶剂体系显得尤为重要.最后,对FDCA产品的国内外应用现状进行了简要分析,并对FDCA产品的发展前景做进一步展望. 相似文献
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合成3,4-二取代呋喃-2,5-二甲酸的简便方法 总被引:1,自引:0,他引:1
报道了一种合成标题化合物的简便方法。在KOH的作用下,1,2-二羰基化合物二水合三聚乙二醛、草酸二乙酯或二苯乙二酮与二甘醇酸二甲酯在环己烷中回流6~8h,缩合成呋喃-2,5-二甲酸、3,4-二羟基呋喃-2,5-二甲酸和3,4-二苯基呋喃-2,5-二甲酸,产率为73.4%~98.6%。 相似文献
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2,5-呋喃二甲酸(FDCA)是合成聚(呋喃二甲酸乙二醇酯)(PEF)等生物基聚酯的重要单体,具有广阔的应用前景。FDCA能否实现低廉、高效的大规模生产,是生物基聚酯开发的关键。目前,FDCA合成的研究广受关注,工业化开发也正在进行中。本文对合成生物基单体FDCA的5-羟甲基糠醛(HMF)路线进行综述,重点介绍了水、高沸点有机溶剂、低沸点有机溶剂、双相体系和离子液体中的糖类脱水合成HMF,无碱水溶液、碱性水溶液和有机溶剂中的HMF氧化合成FDCA以及糖类一锅法合成FDCA的研究进展。在比较各种合成方法的基础上,认为当前应着重研究开发低沸点溶剂中糖类脱水合成HMF以及无碱水溶液或有机溶剂中低廉高效的HMF氧化新方法,并向着糖类一锅法合成FDCA的方向发展。 相似文献
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标题化合物是一种重要的医药中间体,也是合成高效、低毒除草剂麦草畏的关键中间体.以廉价易得的2,5-二氯硝基苯为初始原料,经过水合肼还原、重氮化反应合成2,5-二氯苯酚,再在高温高压下进行羧基化反应合成标题化合物.通过单因素实验,研究了以上反应的关键影响因素,得到了适宜的合成条件,标题化合物的收率65.8%(以2,5-二氯硝基苯计),纯度99.24%,满足应用要求.该合成方法简单经济,产物纯度高、易于分离,收率较高.产物和中间体经过红外光谱和核磁共振波谱分析,表明其特征与标准物一致. 相似文献
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亚氨基二乙酸与二氯亚砜在过量的甲醇或乙醇溶剂中回流8h合成了亚氨基二乙酸二甲酯或亚氨基二乙酸二乙酯,然后与二水合三聚乙二醛在强碱甲醇钠或乙醇钠的作用下,合成了吡咯-2,5-二甲酸二甲酯或吡咯-2,5-二甲酸二乙酯,产率分别为67.6%和70.2%;吡咯-2,5-二甲酸二甲酯或吡咯-2,5-二甲酸二乙酯经碱性条件下水解、酸化合成了吡咯-2,5-二甲酸,总产率为62.4%~66.5%. 相似文献
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用6-甲基炯酸为原料,高锰酸钾为氧化剂,在水相的条件下合成了2,5-吡啶二甲酸。考察了氧化剂种类、原料与氧化剂配比、反应用水的量以及后处理对产品收率和纯度的影响。结果表明,用高锰酸钾为氧化剂,高锰酸钾与6-甲基烟酸的摩尔比为3;反应用水的质量为原料质量的6倍;用酸碱精制法对产品粗品进行精制,在此条件下产品的最终纯度达到99.5%以上,总收率达到70%以上。 相似文献
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David V. Person John W. Fitch Patrick E. Cassidy Keiji Kono V. Sreenivasulu Reddy 《Reactive and Functional Polymers》1996,30(1-3):141-147
A new synthetic route to 2,5-difluoroterephthalic acid (DFTA) was devised and from this several new series of polymers were prepared by polycondensation. This inaugural paper will cover polyesters while subsequent papers will report on keto polyethers, polyamides and other backbones derived from DFTA. DFTA was synthesized from 2,5-difluorotoluene, which was acylated and subsequently converted to the diacid by a several step oxidation process. Various polyesters were prepared by reacting it with numerous bisphenols and diols by solution condensation to give a series of difluoroterephthalate polyesters with viscosities ranging from 0.16 to 0.61 dl/g. Thermogravimetric analyses showed that the polyesters had thermal stabilities up to 480°C in nitrogen; melting temperatures ranged from 127 to 318°C. 相似文献
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This paper addresses a route to synthesize bio-based polymers with an aromatic backbone having a liquid crystalline (LC) phase in the molten state. The LC phase is employed to achieve uniaxial orientation during processing required in e.g. fiber spinning. For this purpose 2,5-furandicarboxylic acid (2,5-FDCA) and O-acetylvanillic acid (AVA), obtained from natural resources, are used as monomers. Similar to the 2,6-hydroxynapthoic acid used to perturb the crystalline packing of poly(oxybenzoate) in the Vectran® series, these bio-based monomers are used to lower the crystal to liquid crystal transition temperature. Considering that the poly(oxybenzoate) can also be obtained from natural resources, the adopted route provides the unique possibility to synthesize bio-based polymers that can be used for high performance applications. To obtain the desired polymers, a synthetic route is developed to overcome the thermal instability of the 2,5-FDCA monomer. Experimental techniques, such as optical microscopy, FTIR spectroscopy, DSC, and TGA are employed to follow the polymerization, phase transitions and evaluate thermal stability of the synthesized polymers. 相似文献
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Liyuan Sun Yajie Zhang Jinggang Wang Fei Liu Zhen Jia Xiaoqing Liu Jin Zhu 《应用聚合物科学杂志》2019,136(11):47186
2,5-furandicarboxylic acid (FDCA), a bio-based monomer, was taken as a sustainable alternative to isophthalic acid (IPA) for the modification of poly(ethylene terephthalate) (PET). Results showed that FDCA was more effective than IPA in terms of reducing the crystallization activity of PET, because FDCA is more rigid and highly polar, which will hinder the PET chain packing during crystallization process. Moreover, modification of PET with FDCA resulted in copolyester with higher glass transition temperature, higher tensile modulus, better optical clarity, and gas barrier property, compared to those of IPA. With the addition of 20 mol % FDCA, the resulted copolyester poly(ethylene 2,5-furandicarboxylate-co-ethylene terephthalate) (PEFT 20) was able to keep high transparency even after being annealed at 110 °C for 40 min. However, when 20 mol % of IPA was added, poly(ethylene isophthalate-co-ethylene terephthalate) (PEIT20) easily turned opaque under the same heat treatment. Therefore, less amount of FDCA was required in order to obtain the PET copolyester with better performance. The result indicated that FDCA had great potential to substitute IPA for the modification of PET from the point of view of industrial application. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47186. 相似文献