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1-环丙基-7-氯-6-(1-哌嗪基)-4-氧-1,4-二氢-3-喹啉羧酸盐酸盐为环丙沙星合成中主要的杂质之一,研究其物化性质对于改善环丙沙星的结晶分离提纯具有重要意义。本文研究了1-环丙基-7-氯-6-(1-哌嗪基)-4-氧-1,4-二氢-3-喹啉羧酸盐酸盐的熔化,分解特性,溶解度与离子强度,温度和pH值的关系,并测定了该物质的离解常数,估算了该物质在水溶液中的活度积。 相似文献
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研究了以邻硝基甲苯为原料,经以Pt/C催化加氢和烷基酮、Pd/C存在下缩合两步合成2-甲基-4-甲氧基二苯胺(DPA),收率分别为71.2%和96.1%。 相似文献
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液相加氢法合成H-酸工艺研究 总被引:3,自引:0,他引:3
介绍了以CaCO3代替氨水进行脱硝物中和,经Na2CO3置换,用催化加氢代替铁粉还原,再进行碱熔,H-酸离析制得H-酸的工艺,重点对液相加氢工艺进行了研究,该工艺砍掉了T-酸离析工序,减少了三废,降低了原料成本,提高了H-酸收率及产品质量,具有一定的经济效益和社会效益。 相似文献
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本文采用改性蓖麻油合成了软段中含不饱和双键的阴离子聚氨酯水分散液(MCPU),将其作为可聚合乳化剂和种子成分同甲基丙烯酸甲酯(MMA)进行共聚,制得了MCPU-PMMA复合乳液。1HNMR谱图显示MCPU中含有双键结构,共聚后双键消失。通过考察单体转化率和复合乳液平均粒径、凝胶量及成膜耐水及甲苯性探讨了影响种子乳液聚合的多种因素:采用过硫酸钾作为引发剂,单体转化率高,乳液粒径小,成膜耐水及甲苯性好;反应的表观活化能Ea为164.86kJ/mol,反应温度控制在70℃较适宜;聚合反应速率Rp∝[I]1.0856,引发剂用量宜控制在聚合有效组份总质量的0.5%。 相似文献
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种子乳液聚合法制备纳米SiO_2/苯丙复合乳液 总被引:2,自引:0,他引:2
采用种子乳液聚合工艺,用经硅烷偶联剂改性后的纳米SiO2原位合成了纳米SiO2/苯丙复合乳液。通过正交实验确定了最佳原料配比和聚合工艺条件,并对复合乳液性能进行了分析与表征。结果表明,当功能单体的用量为单体总量的5%、阴离子乳化剂十二烷基硫酸钠(SDS)与非离子乳化剂辛基苯基聚氧乙烯醚(OP-10)质量比为1颐1、复合乳化剂总量3%、纳米SiO2含量为单体总量的1.5%、聚合温度为80℃时,可制备具有良好综合性能的复合乳液,其涂膜耐水性、硬度、附着力等均优于普通苯丙乳液。该复合乳液乳胶粒粒度呈单峰分布,平均粒径为101nm,具有核/壳结构。 相似文献
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乳液聚合方法研究进展 总被引:2,自引:0,他引:2
乳液聚合方法具有各方面的优点和广泛的应用范围,因此,受到人们的广泛关注。本文介绍了乳液聚合的优缺点,并着重介绍了一些新的乳液聚合方法及其原理、特点、应用以及中外最新的一些研究成果。 相似文献
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G. W. Ceska 《应用聚合物科学杂志》1974,18(8):2493-2499
An emulsion polymerization process is reported for the production of high-solids, surfactant-free styrene/butadiene latices. With this procedure latices require no surfactants, for stabilization is built into the emulsion particles by means of copolymerized acid monomers. This “pH variable” method is a two-step, batch-on-batch polymerization. In the first step, all the ingredients are present in the reaction mixture; however, only enough styrene and butadiene is added to reach a low solids content. This step, carried out at low pH, produces a carboxylated seed latex. On raising the pH of this low-solids emulsion, the copolymerized carboxyl groups ionize, and the now highly charged latex particles provide an expedient locus for the generation of stable, highsolids latices. Neutralizing the carboxyl groups of the seed latex before adding the remaining monomers induces the highly hydrophilic carboxyl anions to remain on the surface of the latex particle, nearer to the aqueous environment of the surrounding media. Hence, the maximum stabilization capacity of the acid monomers is utilized. The process was evaluated to ascertain the effects of the following variables: the particle size and solids content of the first step, the nature of the base used to raise the pH, the pH of the dispersion prior to the second step, and the effect of the acid monomer on the latex stability. 相似文献
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摘要用叔碳酸乙烯酯(Veova10)单体对醋酸乙烯酯乳液进行改性,采用种子聚合的方法,以过硫酸钾为引发剂,使用阴离子和非离子复配的乳化剂,加入一定量的丙烯酸酯类单体,可制得耐碱性、耐水性、耐候性都非常好的乳液。此共聚乳液特别适合用作内墙和外墙乳胶漆的基料。 相似文献
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S. Sajjadi 《应用聚合物科学杂志》2001,82(10):2472-2477
Semibatch emulsion polymerization processes with a monomer emulsion feed are of great importance in both academia and industry. Monomer emulsion feeds can be applied to semibatch reactors using either a stream of an emulsified monomer or two streams of a neat monomer feed and an aqueous solution of an emulsifier. The effect of the feeding policy on the rate of polymerization and on the secondary particle formation was studied for a seeded semibatch emulsion polymerization of styrene. When a single-stream monomer emulsion feed is applied to a semibatch process, the monomer-swollen micelles formed in the feed might become the locus of initiation upon entering the reaction vessel. Under the conditions of this study, the application of monomer emulsion feed in either one stream or two streams did not result in secondary particle formation. The incoming monomer-swollen micelles were disintegrated to supply emulsifier molecules for the stability of growing particles, before they can capture radicals and become polymer particles. The rate of polymerization was found to be independent of the way that the monomer emulsion feed is added. In the absence of nitrogen, the rate of polymerization decreased more appreciably for the monomer emulsion feed, due to the oxygen dissolved in the emulsified monomer. The number of particles, however, was not affected by the purging policy. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 2472–2477, 2001 相似文献