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科聚亚公司2007年3月9日宣布其四溴苯酐二醇(PHT4-diol)阻燃剂产品的价格将提高5%,并将于2007年4月1日起在合同允许范围内生效。 相似文献
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研究了新型阻燃剂5,6,7,8-四溴-1,2,3,4-四氢化萘(TBT)的合成方法,并对工艺条件进行了研究。总收率可达50.3%。 相似文献
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介绍了氯化溴地在盐酸和卤代烃的多相介质中合成2,4,6--三溴苯酚的方法,系统地研究了各种因素对合成TBP的影响。确定了优惠工艺条件,并提出了产品的后处理方法。 相似文献
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The oxidation of naphthalene (1) (Scheme 1) in dichloromethane or acetonitrile with excess ozone gives phthalic aldehyde (3), 2-formyl benzoic acid (4) and phthalic anhydride (8). Small amounts of the (E)- and (Z)-isomer of 3-phenyl-(2-formyl)-propenal (10) and (11) are also observed in some cases. The reaction is faster in acetonitrile than in dichloromethane owing to the higher solubility of ozone in the former solvent. The reaction is faster on lowering the temperature because of the increase of the concentration of ozone in solution at lower temperature. With a 1:1 or a 1:2 naphthalene:ozone ratio high conversion and low selectivity for the anhydride (8) is observed. 相似文献
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本实验采用"准一步法"以二乙醇胺和邻苯二甲酸酐为原料先合成了AB2型中间体Ⅰ,中间体Ⅰ分别以苯、甲苯和二甲苯为带水剂进行缩聚反应生成端基为羟基的超支化聚酰胺Ⅱ,然后采用不同封端剂(苯甲酸,α-甲基丙烯酸,乙酸)进行端基改性得到最终产物Ⅲ.实验结果表明,较适宜的反应时间为:第一步1小时,第二步10小时(甲苯为带水剂),第三步10小时.同时确定出甲苯为带水剂、对甲苯磺酸为催化剂较好,产物收率大于94%,粘度在0.18~0.21dL/g,较易溶于酰胺类物质,并且热重检测产物有较好的热稳定性. 相似文献
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以四乙基溴化胺为催化剂,1,4-丁二醇为起始剂,邻苯二甲酸酐和环氧氯丙烷为原料合成聚酯树脂,采用傅立叶红外光谱(FT-IR)和核磁共振(1H-NMR)对产物的结构进行表征,并考察了催化剂用量和反应温度对合成聚酯树脂的影响.结果表明,合成聚酯树脂的端基为羟基,且随着温度升高和催化剂用量增加,反应速率增加,合适的反应条件为... 相似文献
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Information concerning the oxidation of o-xylene and naphthalene, the two main processes for producing phthalic anhydride, is updated and analyzed. New techniques for the preparation of catalysts, all based in the impregnation method and involving the control of parameters such as pH and ionic strength of solutions, are described; the performance of the resulting catalysts is compared with that of catalysts prepared by other methods. Sulfur-containing substances and promoters such as Ag, P, Nb, and Sb have been shown to enhance catalyst performance; studies of their effect on the surface area, acidic properties, and stabilization of the oxidation state of vanadium in supported V2O5 catalysts are described. The latest attempts to correlate the physicochemical characteristics of the catalysts with their catalytic features are analyzed. FTIR, Raman spectroscopy, adsorption of bases, 51V-NMR, XRD, XPS, SIMS, and electrical conductivity have been used in the study of V2O5/TiO2 catalysts, allowing further understanding of the effects of the properties such as acidity and the state of oxidation of the surface. Particular emphasis has been given to the presence of VIV, which is thought to cause lower selectivity to phthalic anhydride. For o-xylene oxidation, the formation of involatile by-products has been established as a secondary reaction, accounting for the poor carbon balances obtained under some experimental conditions. Involatile by-products, whose formation has been associated with the presence of strong acid sites, can adsorb on the catalyst surface, leading to deactivation, or undergo total combustion, acting as a source of CO2. Attempts to quantify and characterize those by-products are described. The modeling of the reaction using both fixed- and fluidized-bed reactors, including the study of parameters such as the inlet temperature and the bath temperature, is analyzed. Models considering catalyst deactivation have been also developed; for o-xylene oxidation, deactivation has been associated with processes both reversible, such as changes in the oxidation state of vanadium, deposition of involatile compounds, and irreversible, such as structural changes, decrease in surface area, sintering, and variation of the promoter concentration at the catalyst surface. The study of V2O5/TiO2 EUROCAT catalysts, involving a number of European laboratories, is reviewed, and their performance is compared with that of other V2O5/TiO2 catalysts. 相似文献
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本文主要针对萘气相催化氧化制备1,4-萘醌的工业副产物邻苯二甲酸酐、顺丁烯二酸酐分别在水中的溶解度进行固一液相平衡的基础研究。 相似文献