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简述了均苯四甲酸二酐任涂料工业中的主要用途。介绍了均四甲苯法、偏三甲苯烷基化法、一氧化碳法等均苯四甲酸二酐的生产方法,对各种生产方法进行了评述,同时对我国均酐生产提出了一些合理化建议。 相似文献
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本文介绍了氧化还原法测定均苯四甲酸二酐催化剂中钒离子价态,这对催化剂的制备及活性评价具有重要意义。 相似文献
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对均四甲苯气相氧化法制均苯四甲酸二酐所用催化剂的研究进行了综述,重点叙述了国内外关于催化剂活性成分的研究状况,并介绍了通过改进载体和制备方法提高均苯四甲酸二酐收率的措施,为高性能催化剂的开发提供思路. 相似文献
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朱光衡 《化学工业与工程技术》2005,26(6):35-36
针对某均苯四甲酸二酐装置仪表控制存在的问题,采用国产工控机和智能模块及组态软件,构成以先进的控制总线技术为基础,实现均苯四甲酸二酐生产装置的集散控制系统。阐述了DCS系统的构成、测控方案及主要性能,比较了该装置采用DCS控制前后的实际运行效果。 相似文献
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This article describes the curing and thermal behavior of diglycidyl ether of bisphenol A with phthalic anhydride (PA)/pyromellitic anhydride/diaminodiphenyl sulfone (DDS) or a mixture of anhydrides and amines in varying ratios as curing agents. The kinetics of the curing behavior was investigated with a multiple‐rate method. The activation energy of the curing reaction as determined in accordance with Ozawa's method was found dependent on the structure of the anhydride and on the ratio of amines to anhydrides. The activation energy was highest with sample DP3 (0.25 : 0.75) and DM3 (0.25 : 0.75). We evaluated the thermal stability of epoxy resin, cured isothermally, by recording thermogravimetric traces in a nitrogen atmosphere. The char yield was highest for resins cured with a mixture of DDS and PA (0.5 : 0.5) and a mixture of DDS and pyromellitic dianhydride (0.25 : 0.75). © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 3919–3925, 2006 相似文献
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Summary Four polycondensates have been prepared from 9,10-anthracene-diol and succinic anhydride, phthalic anhydride, pyromellitic dianhydride and 1,4,5,8-naphthalene tetracarboxylic dianhydride. Thermal stabilities, dielectric and conductivity characteristics of these condensates indicate that these properties are influenced by the nature of the anhydride moiety. 相似文献
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介绍了重力热管换热器的工作原理、结构和传热特性,以及重力热管换热器在均苯四甲酸二酐生产中的应用情况。 相似文献
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Polystyrene has been chemically modified by Friedel-Crafts acylation reaction with trimellitic anhydride in the presence of anhydrous aluminium chloride as catalyst. The product has been characterized in respect of its structure and physicochemical properties by measuring its total capacity, thermal stability and the behaviour to pH metric titration. The thermal characteristics of the trimellitic anhydride modified polystyrene have been compared with the same for phthalic anhydride and pyromellitic dianhydride modified polystyrene in the light of their structural characteristics. 相似文献
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Shanxi anthracite was subjected to oxygen-oxidation at 250°C in all aqueous solution of potassium hydroxide to produce solid benzene polycarboxylic acid (BPCA), and then the BPCA were selectively decarboxylated in the mixed medium of concentrated H2SO4 and KHSO4 to produce crude pyromellitic acid (PA). Pure PA was obtained by solvent recrystallization method, and the best solvent was 2-pentanone. Pure pyromellitic anhydride (PMDA) was gotton by heating pure pyromellitic acid in vacuum chamber at 260°C for 3 h. The remaining BPCA which through 2-pentanone recrystallization was isomerizated with consistent temperature at 420°C for 2 h. Appropriation pH of BPCA, initial pressure of carbon dioxide and cadmium carbonate catalyst were provided to produce crude terephthalic acid (TPA). Pure TPA was obtained by washing and drying the crude TPA precipitation. 相似文献
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均聚型线性(一维)聚合酞菁亚铁的合成研究 总被引:1,自引:0,他引:1
以均苯四甲酸酐、邻苯二甲酸酐、氯化亚铁为起始化合物,在钼酸铵作用下,经亲核加成反应生成对二甲酸酐酞菁亚铁前驱体,以化合物对二甲酸酐酞菁亚铁为前驱体,在钼酸铵的作用下发生多环合四聚反应,得到均聚型线性(一维)聚合酞菁亚铁,分别用紫外可见光谱、红外光谱及X射线衍射确认了聚合物的结构。 相似文献
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陈秋云;王益龙;刘佳;王会 《中国塑料》2011,25(10):72-76
分别采用甲苯二异氰酸酯、三氧化二锑、邻苯二甲酸酐、均苯四酐、萘四甲酐以及均苯四酐和邻苯二甲酸酐混合物作为聚对苯二甲酸乙二醇酯(PET)瓶片的扩链剂,研究了反应挤出后产物特性黏度的变化。结果表明,甲苯二异氰酸酯、三氧化二锑、邻苯二甲酸酐和萘四甲酐对PET瓶片的扩链效果较弱;均苯四酐可明显提高PET的特性黏度。均苯四酐和邻苯二甲酸酐复配后的扩链效果最为显著;当均苯四甲酸二酐用量为0.3 %、邻苯二甲酸酐用量为0.2 %时,PET的特性黏度达到0.96 dL/g。 相似文献
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PA封端型聚酰亚胺的合成与表征 总被引:3,自引:2,他引:1
以均苯四甲酸二酐(PMDA)和自制的1,3-双(4-氨基苯氧基)苯(TPER)在邻苯二甲酸酐(PA)封端的情况下溶液缩聚得到聚酰胺酸(PAA),通过溶液亚胺化和固相亚胺化相结合得到聚酰亚胺(PI).用傅立叶变换红外光谱仪、乌氏粘度计和热失重分析仪对PI进行了结构表征和性能测试,分析了封端剂加入量、亚胺化方式对PI性能的影响.结果表明,封端剂的加入可有效降低PI的粘度,两种亚胺化方式的结合可以降低PI的最终亚胺化温度,得到的PI热稳定性高. 相似文献
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A series of silatrane based imide resins having different end-caps were prepared by reacting 1-(3-aminopropyl)silatrane with 5-norbornene-endo-2,3-dicarboxylic anhydride (nadic anhydride), 5-methyl-5-norbornene-2,3-dicarboxylic anhydride (methyl nadic anhydride), hexachloronadic anhydride, maleic anhydride, benzophenone-3,3′,4,4′-tetracarboxylic dianhydride or pyromellitic dianhydride in dimethylacetamide. Structural characterisation of the resins was done by elemental analysis and IR. In DSC traces of these resins, an exothermic transition associated with crosslinking was observed above 230°C. Thermogravimetric studies revealed a multistep decomposition reaction. Residual weight at 800°C in nitrogen was found to depend on the backbone structure and ranged from 32–60%. 相似文献
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Copolycondensates have been prepared from carbazole, poly(N-vinylcarbazole) and various aromatic anhydrides, e.g., phthalic anhydride, trimellitic acid anhydride, pyromellitic dianhydride, naphthalene tetracarboxylic dianhydride, and benzophenone tetracarboxylic dianhydride in presence of the Friedel–Crafts catalyst anhydrous zinc chloride at high temperature. The polymers have been characterized by elemental analyses and IR spectroscopy. Thermal stabilities, dielectric, and conductivity behaviors of these polymers have also been evaluated and it has been observed that these properties show interesting differences depending upon the nature of the anhydride. 相似文献