四溴苯酐合成新方法研究

介绍一种以邻二甲苯为原料,经苯环溴化、侧链溴化、酯化、水解、氧化、脱羧制取有机阻燃剂四溴苯酐的合成新方法,产物总收率为76．0％,HPLC法测得含量达98．3％。合成过程采用溴素回收,降低了生产成本,明显改善了操作条件,消除了传统方法对环境的污染。     

降低阻燃剂四溴苯酐中游离硫酸的方法研究

通过剖析四溴苯酐中游离硫酸形成原因,对原有的生产工艺进行优化改进,合成得到了熔点高、游离硫酸含量低的四溴苯酐。     

I_2-AlCl_3催化合成四溴苯酐的工艺研究

针对国内四溴苯酐生产现状,在对溴化反应过程机理分析的基础上,对反应过程进行优化,得到了较优的反应条件及操作过程:以I2、AlCl3作为反应的复合催化剂,用量为苯酐的2%,采用分段控温缓慢加溴的操作方式,最高反应温度140℃,反应时间5￣6h,四溴苯酐的收率为96%,熔点276.3￣277.2℃,硫酸含量0.13%。     

科聚亚提高四溴苯酐二醇阻燃剂价格

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。     

新型阻燃剂TBT的合成

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％。     

科聚亚提高四溴苯酐二醇阻燃剂价格

美国康涅狄格州Middlebury，2007年3月9日——科聚亚公司（纽约证券交易所代码：CEM）宣布其四溴苯酐二醇（PHT4dio1）阻燃剂产品的价格将提高5％，并于2007年4月1日起在合同允许范围内生效。     

阻燃剂四溴苯酐的热分解动力学研究

用热重-差热分析法对阻燃剂四溴苯酐的热分解过程进行了动力学研究.结果表明四溴苯酐的热分解过程分两步进行.采用Dbyle-Ozawa积分法和Achar-Brindley-Sharp-Wendworth微分法对两步热分解过程分别进行分析,在30种机理函数中进行筛选,得到了四溴苯酐的两步热分解的最概然机理及动力学特性参数.     

氯化溴法合成2,4,6——三溴苯酚的研究

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。     

溴系阻燃剂十溴二苯醚的合成

本文简述了以二苯醚为原料，经三氯化铝催化合成十溴二苯醚的方法，并给出最佳工艺条件。     

The Synthesis of Phthalic Anhydride via Ozonation of Naphthalene

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.     

邻苯二甲酸酐和二乙醇胺合成超支化聚合物的研究

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.     

邻苯二甲酸酐与环氧氯丙烷反应合成聚酯树脂

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...     

苯酐国内市场分析

分析了国内苯酐的供需现状及发展前景,指出了影响我国苯酐行业未来发展的主要因素。     

世界苯酐工业发展近况

阐述了苯酐的全球市场概况、主要生产工艺和世界各地的供需情况，并对未来5年的发展趋势进行了预测。     

Synthesis of Phthalic Anhydride: Catalysts,Kinetics, and Reaction Modeling

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 V^IV, 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.     

世界苯酐工业发展近况

阐述了苯酐的全球市场概况、主要生产工艺和世界各地的供需情况,并对未来 5年的发展趋势进行了预测.     

苯酐生产现状及展望

介绍了苯酐的主要生产技术及其进展,分析了国外苯酐的生产及消费状况,指出我国苯酐生产技术与国外先进水平间的差距,并为我国苯酐工业的健康发展提出了几点建议。     

邻苯二甲酸酐、顺丁烯二酸酐的溶解度分析

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。