液液二相系における界面特異的反応過程の研究

液-液两相体系中界面特异性反应过程的研究

• 批准号: 10440220
• 负责人: KAKIUCHI Takashi
• 金额: $ 9.09万
• 依托单位: KYOTO UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B).
• 财政年份: 1998
• 资助国家: 日本
• 起止时间: 1998 至 2000
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-10440220/
• 关键词: liquid-liquid two-phase systems; interface-specific reaction processes; azo coupling reactions; ary diazonium ions; radical polymerization; polystyrene; charge-transfer coupling; interfacial instability; エマルション重合; フルオロメトリー; イオン移動; 液液界面; 相間移動触媒

1. Ac-voltammetry and ac-modulated interfacial voltfluorometry revealed that the slower rate of the transfer of xanthene-type dye anions across the liquid-liuqid interface is ascribed to the transient adsorption of these ions at the interface. Even ions that are considered to have no surface activity can stay some time at the interface, resulting in the slower rate of the interfacial ion transfer. 2. It is demonstrated theoretically that the potential dependent adsorption and partition of ionic surfactants results in the maximum adsorption at the potential around its standard ion-transfer potential. The generality of the conclusion signifies its importance in dealing with various interfacial phenomena in the presence of ioinic surfactants in liquid-liquid two-phase systems. 3. A new criterion of instability of liquid-liquid two-phase systems containing ionic surfactants is proposed. The dependence of the adsorption on the phase-boundary potential can lead to the positive curvature of t … More he electrocapillary curve, which means the negative capacitance of the interface. The interface becomes unstable under this physically unrealistic condition. The spontaneous emulsification, a long-standing riddle in surface chemistry, can be explained by this new concept. 4. The fusion of emulsion particles to the polarized liquid-liquid interface can be monitored electrochemically. The discrete nature of the fusion event is exhibited as a train of current spikes. When the area of the interface is on the order of square centimeter, the fusion takes place as an avalanche, that is, the transfer of many smaller particles triggered by the fusion of a large emulsion particle, whereas a single fusion event is monitored when a micro liquid-liquid interface is employed. 5. A two-phase azo coupling can be quantitatively studied using electrochemical techniques. This reaction is best described as ErCiEr, that is, the reversible ion transfer, a succeeding irreversible chemical reaction in a homogeneous bulk solution phase, and the following back transfer of protons to the aqueous phase. Aryl-azo cations are reduced in the organic phase containing a reductant. The produced aryl-radicals can initiate the radical polymerization at the interface. 6. The mode of the coupling of electron transfer and ion transfer reactions at the liquid-liquid interface has been studied both experimentally and theoretically. In the case of thin-organic-layer covered electrodes dipped in an aqueous solution, the criterion has been quantitatively established for accurately determining the rate of electron tranfer reactions at the liquid-liquid interface. Less

1.交流伏安法和交流调制界面电压荧光法表明，吨型染料阴离子在液-液界面上的转移速率较慢，这归因于这些离子在界面上的瞬时吸附。即使被认为没有表面活性的离子也可以在界面处停留一段时间，导致界面离子转移的速率较慢。2.从理论上证明了离子型表面活性剂的吸附和分配是电位依赖性的，在其标准离子迁移电位附近的电位处吸附最大。该结论的普遍性表明它对处理离子表面活性剂存在下的液-液两相体系中的各种界面现象具有重要意义。3.提出了含离子表面活性剂的液液两相体系不稳定性的新判据。吸附对相界势的依赖性导致了t的正曲率 ...更多信息 电毛细曲线，表示界面的负电容。在这种物理上不现实的条件下，界面变得不稳定。这一新概念可以解释表面化学中的自发乳化现象。4.乳液颗粒与极化的液-液界面的融合可以用电化学方法监测。融合事件的离散性表现为一系列电流尖峰。当界面的面积为平方厘米量级时，融合以雪崩的形式发生，即，由大乳液颗粒的融合触发的许多较小颗粒的转移，而当采用微液-液界面时，监测单个融合事件。5.两相偶氮偶联可以用电化学技术定量研究。该反应最好描述为ErCiEr，即可逆离子转移，在均匀本体溶液相中的随后的不可逆化学反应，以及随后质子向水相的反向转移。芳基偶氮阳离子在含有还原剂的有机相中被还原。产生的芳基自由基可以引发界面处的自由基聚合。6.从实验和理论两方面研究了液-液界面上电子转移和离子转移反应的耦合模式。在薄的有机层覆盖的电极浸在水溶液中的情况下，已定量地建立了用于准确地确定在液-液界面处的电子转移反应的速率的标准。少

项目成果

Takashi Kakiuchi: "Adsorption at polarized liquid-liquid interfaces, in A.G.Volkov ed.,"Liquid Interfaces in Chemical, Biological, and Pharmaceutical Applications"Marcel Dekker. 17 (2001)

Takashi Kakiuchi：“极化液-液界面的吸附，A.G.Volkov 编辑，“化学、生物和制药应用中的液体界面”Marcel Dekker. 17 (2001)

Takashi Kakiuchi and Yoshikazu Teranishi: "A.c. voltammetric evidence for the transient adsorption of asymmetric ions in the transfer across the nitrobenzene | water interface"Electrochem.Commun.. (In press).

Takashi Kakiuchi 和 Yoshikazu Teranishi：“在硝基苯 | 水界面转移过程中不对称离子瞬时吸附的交流伏安证据”Electrochem.Commun.（正在出版）。

Takashi Kakiuchi: "Potential-dependent Adsorption and Partitioning of Ionic Components at Liquid-Liquid Interfaces"J.Electroanal.Chem.. 496. 137-142 (2001)

Takashi Kakiuchi：“液-液界面离子组分的电位依赖性吸附和分配”J.Electroanal.Chem.. 496. 137-142 (2001)

Young-Tae Kong and Takashi Kakiuchi: "Electrochemical Determination of the Lipophilicity Scale of Arenediazonium Ions Based on the Ion Transfer Across the Liquid Liquid Interface"J. Electroanal. Chem.. (in press.).

Young-Tae Kong 和 Takashi Kakiuchi：“基于跨液-液界面的离子转移电化学测定芳烃重氮离子的亲油性尺度”J。

Takashi Kakiuchi: "Voltage-Controlled Fluorometry of the Transfer of Nonfluorescent Ions across the 1,2-Dichloroethane/Water Interface using Fluorescent Ionophores" Analytical Chemistry. Volume 70 Number 19. 4152-4156 (1998)

Takashi Kakiuchi：“使用荧光离子载体对非荧光离子跨 1,2-二氯乙烷/水界面转移的压控荧光测定”分析化学。