四溴双酚A的合成研究

四溴双酚A以95%无水乙醇为溶剂,以双酚A和溴素为原料合成。在双酚A与溴素摩尔比一定的条件下,通过改变反应时间进行合成实验,结果表明:最佳反应时间2.5 h;在反应时间一定的条件下,通过改变双酚A与溴素摩尔比进行合成实验,结果表明:最佳原料摩尔比1∶2.6。在此反应条件下合成具有高收率,高质量,操作简便等优点。     

四溴双酚A的合成新工艺研究

研究了一种合成四溴双酚Ａ的新的合成方法，此法操作简便、无三废产生，且收率高。对制备卤代双酚Ａ或卤代双酚Ｓ具有普遍的适用性。     

双酚A合成四溴双酚A双(2,3一二溴丙基)醚的工艺研究

将四溴双酚A和四溴双酚A双(2,3-二溴丙基)醚(简称八溴醚)两产品的工艺技术有机地结合起来,探讨了在氯苯溶剂中以双酚A为原料直接合成四溴双酚钠,并在乙醇溶剂中与氯丙烯合成中间体四溴双酚A双烯丙基醚的过程及分析了各种影响因素,开发出一条由双酚A直接制备八溴醚的工艺路线。该工艺的主要特点是四溴双酚A以钠盐的形态直接转入醚化工序,缩短了工艺流程,减少了溶剂损失。     

四溴双酚A二缩水甘油醚的合成

通过探索温度、加碱方式、碱用量等因素对合成四溴双酚A二缩水甘油醚的影响，优化出较好的合成条件。对溶剂回收、萃取液水洗、萃取液干燥等条件对产品环氧值的影响进行了研究。     

双酚A合成四溴双酚A双（2，3-二溴丙基）醚的工艺研究

将四溴双酚A和四溴双酚A双(2,3-二溴丙基)醚(简称八溴醚)两产品的工艺技术有机地结合起来,探讨了在氯苯溶剂中以双酚A为原料直接合成四溴双酚钠,并在乙醇溶剂中与氯丙烯合成中间体四溴双酚A双烯丙基醚的过程及分析了各种影响因素,开发出一条由双酚A直接制备八溴醚的工艺路线.该工艺的主要特点是四溴双酚A以钠盐的形态直接转入醚化工序,缩短了工艺流程,减少了溶剂损失.     

四溴双酚A制造工艺评述

本文对四溴双酚A开发与应用作了简要介绍,评述和比较了几种常见的四溴双酚A制造工艺。     

阻燃剂四溴双酚A的环境友好合成工艺研究

研究了过氧化氢存在下以双酚A与液溴为原料合成四溴双酚A的工艺条件 ,考察了n(Br2 )∶n(双酚A)、n(H2 O2 )∶n(Br2 )、反应时间等因素对反应的影响 ,并通过正交实验 ,优化了合成工艺条件。实验表明 :n(Br2 )∶n(双酚A) =2 2 0∶1 0 0 ,n(H2 O2 )∶n(Br2 ) =1 10∶1 0 0 ,反应温度15～ 2 5℃ ,每克双酚A加水 3mL时收率接近 99% ,溴利用率达 99%     

四溴双酚A的合成新工艺

对以次氯酸钙为氧化剂合成四溴双酚A的生产工艺做了研究,该工艺具有原料价廉易得、反应条件温和、产品收率高等优点,具有广阔的推广、应用前景。     

四溴双酚A二缩水甘油醚的合成

溴化环氧树脂是一类特种环氧树脂，具有优异的本质阻燃性能，主要用作电子电器元件的灌装料、防腐剂、粘合剂等材料。溴化环氧树脂阻燃剂是近几年开发出的新型聚合物型溴系阻燃剂之一，具有良好的阻燃性能、粘合性能和热稳定性，毒性低，价格低廉，使用安全，性能平衡性好，     

Interfacial synthesis and characterization of random and segmented block bisphenol A–tetrabromobisphenol A copolycarbonates

The chain sequence architecture of bisphenol A–tetrabromobisphenol A copolycarbonates depends on the process employed to prepare them. An interfacial process involving a single-step phosgenation produces a segmented block copolymer, contrary to previous assumptions. An interfacial two-step phosgenation process allows the preparation of random copolycarbonates. In each process the control of the pH of the acqueous phase of the two phase reaction mixture is required to achieve complete comonomer conversion to copolymer and to obtain the desired sequence architecture. The chain sequence architecture of these copolycarbonates can be estimated by examination of their Fourier transform infrared spectra. The relative bandwidth of the carbonate stretching band is roughly proportional to the copolycarbonate number average sequence length, allowing the facile distinction between block and random copolymers. The number average sequence lengths of these copolycarbonates were quantified by carbon-13 NMR spectroscopy. These analyses showed that the one-step phosgenation process yields segmented block copolycarbonates having number average sequence lengths from about 4 to 9, and the two-step phosgenation process produces random copolycarbonates having sequence lengths from 1.6 to 2. The distribution of the aromatic carbon triads of these random copolymers shows them to have an alternate-segmented block architecture, which is consistent with the synthesis conditions, rather than a statistically random distribution of comonomer segments. Dynamic mechanical analysis of two of these copolycarbonates shows a dependence of their low temperature secondary transitions on the copolymer sequence structure. A segmented block copolycarbonate, having a number average sequence length of about 4, displays two distinct peaks in its tan δ curve at temperatures corresponding to those transitions observed in the respective homopolymers. The tan δ curve of a random copolycarbonate shows a single low temperature secondary transition midway between those of the homopolymer. © 1994 John Wiley & Sons, Inc.     

生产四溴双酚A的新技术

以双酚A、溴水和过氧化氢为原料,采用非均相催化反应技术合成四溴双酚A的新工艺。该工艺成本低、时间短、收率高、产品质量好,环境污染少,设备不易腐蚀。     

超临界连续水热法制备无机纳米材料

介绍了超临界连续水热法用于制备无机纳米材料近年来所取得的研究成果。主要介绍了此方法在反应器设计、掺杂型纳米材料的制备及纳米材料的原位改性3方面的研究进展,并对未来的发展进行了展望。     

微反应器内苯甲醚连续合成

苯甲醚是一种重要的溶剂和有机合成中间体，以往通过间歇反应合成，存在生产效率低下、操作周期长等问题，亟需开发连续化的生产装置和技术。提出以苯酚钠水溶液和硫酸二甲酯为原料通过连续微反应器合成苯甲醚的方法。该方法利用微混合器和局部收缩的反应管道强化反应物的混合，在近似绝热的反应条件下快速完成反应过程。报道了苯酚钠浓度、反应物流量和反应物摩尔比对于微反应器内苯酚钠转化率和硫酸二甲酯利用率的影响规律。与文献报道的间歇反应进行了对比，揭示了微反应技术的优势。     

Continuous spin detonation of synthesis gas-air mixtures

Regimes of continuous detonation burning of synthesis gas-air mixtures in transverse (spinning) detonation waves are obtained for the first time in an annular cylindrical flow-type combustor. Carbon oxide-hydrogen mixtures with volume proportions of [CO]/[H₂] = 1/1, 1/2, and 1/3 are studied in a wide range of fuel-to-air equivalence ratios. The maximum detonation wave velocity equal to 1.57 km/s is observed for the mixture of CO + 3H₂ + air with a moderate (about 15%) excess of the fuel. The limits of existence of continuous detonation in terms of the equivalence ratio and the minimum specific flow rate of the mixture are determined. The range of detonation regimes obtained is constructed in the coordinates of the equivalence ratio-specific flow rate of the mixture.     

油酸甲酯连续合成工艺及其动力学研究

在固定床反应器中,以阳离子交换树脂为催化剂,油酸与甲醇液液并流反应制备油酸甲酯。考察了反应各影响因素,获得较适工艺条件为:催化剂装载量20 g,醇酸摩尔比2∶1,反应温度60℃,停留时间40 min。在此条件下,油酸转化率可达99.43%。对油酸与甲醇的反应动力学进行了研究,以拟均相模型对实验数据进行拟合,得出30℃、40℃、50℃、60℃下的正、逆反应速率常数。反应速率随温度的升高而加快,二者关系符合Arrhenius方程,该反应的活化能为60.687 kJ/mol。     

Continuous synthesis of metal nanoparticles in supercritical methanol

Metal nanoparticles were synthesized continuously in supercritical methanol (scMeOH) without using reducing agents at a pressure of 30 MPa and at various reaction temperatures ranging 150-400 °C. Wide angle X-ray diffraction (WAXD) analysis revealed that metallic nickel (Ni) nanoparticles were synthesized at a reaction temperature of 400 °C while mixtures of nickel hydroxide (α-Ni(OH)₂) and metallic Ni were produced at lower reaction temperatures of 250-350 °C. In contrast, metallic silver (Ag) nanoparticles were produced at reaction temperatures above 150 °C while metallic cupper (Cu) nanoparticles were produced at reaction temperatures above 300 °C. Mixtures of copper oxide (CuO and Cu₂O) and metallic Cu were produced at lower reaction temperatures of 250 °C. Scanning electron microscopy (SEM) showed that the particles size and morphology changed drastically as the reaction temperature increased. The average diameters of Ni, Cu and Ag particles synthesized at 400 °C were 119 ± 19 nm, 240 ± 44 nm, and 148 ± 32 nm, respectively. The scMeOH acted both as a reaction medium and a reducing agent. A possible reduction mechanism in scMeOH is also presented.     

微管反应器中硝基氯苯的连续合成

芳香族化合物的硝化是快速、强放热反应,采用连续硝化工艺可降低间歇操作可能引起的潜在风险。本文采用可视化方法和计算流体力学（CFD）模拟研究微管内流动状况的基础上,在体积为10mL的微管反应器中进行了氯苯连续硝化反应,探究了停留时间、温度、混酸比（硝酸与硫酸的摩尔比）、相比（硝酸与氯苯的摩尔比）对反应转化率、收率、产物邻对比和选择性的影响。结果表明,氯苯和混酸两相在内径为1mm的微通道内呈现出的Taylor流流型可以强化传质传热的效率,提高宏观反应速率。在停留时间为8min、温度80℃、混酸比=1∶1.5、相比=1∶1时,产物中邻对比在0.7~0.8之间,氯苯单程转化率为81.24%,一硝基氯苯的选择性为93.77%。采用连续硝化后,反应停留时间大幅降低,一硝基氯苯的邻对比明显提高。相比于传统釜式工艺,微管反应器内连续硝化更加安全、高效。     

Effect of tetrabromobisphenol A diallyl ether on the flame retardancy of high impact-strength polystyrene

The effect of tetrabromobisphenol A diallyl ether (TBBA–DAE) on the flame retardancy of high impact-strength polystyrene (HIPS) was studied and compared with that of tetrabromobisphenol A (TBBA). Experimental results showed that the flame retardancy of TBBA–DAE was superior to that of TBA by thermomixing in the solid state. However, this phenomenon was not obvious by mixing in solution. This effect might result from the bromination of HIPS by the modified Claisen rearrangement of TBBA–DAE during thermomixing in the solid state. Simultaneous addition of the mixture of TBBA–DAE or TBBA with diphenyl isooctylphosphite (DPIOP) into HIPS caused a synergistic effect of flame retardancy and the effect of TBBA-DAE was better than that of TBBA.     

微通道反应器中乙酰乙酸甲酯的连续流合成工艺

传统的间歇反应合成存在温度不易控制、生产能力低、时间长等一系列问题,而微通道反应器可大幅度提高反应过程中的资源和能量的利用效率,减小过程系统的体积或提高单位体积的生产能力,实现化工过程强化、微型化和绿色化。本工作以双乙烯酮与甲醇为原料,探究在变径脉冲结构的微通道反应器中合成乙酰乙酸甲酯新方法。对催化剂类型、物料配比、停留时间、反应温度及催化剂用量进行了考察分析,最佳条件组合结果显示,当催化剂选择甲醇钠,且双乙烯酮:甲醇:甲醇钠=1:1.1:0.02(摩尔比),反应温度为90℃,停留时间为90 s时,双乙烯酮的转化率达100%,乙酰乙酸甲酯的选择性达96.8%,用此方法可以直接体现微通道反应器连续流合成的优势。