Nanostructured Material Synthesis in a Self-Assembled Surfactant Mesophase

自组装表面活性剂中间相纳米结构材料的合成

• 批准号: 9909912
• 负责人: Vijay John
• 金额: $ 46.92万
• 依托单位: Tulane University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-01-01 至 2004-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9909912&HistoricalAwards=false
• 关键词: Nanostructured; Material; Synthesis; Self; Assembled

ABSTRACTCTS-9909912John, Vijay/Tulane U.We propose a collaborative project to develop new nanostructured materials by exploiting the potentially templating environment of a self-assembled surfactant gel phase. The novelty of the gel is the fact that it contains equal volumes of water and an oil phase, thus opening up several possibilities of synthesis in dual hydrophobic and hydropbilic microenvironments. Our hypothesis is that the spatial immobilization of the hydrophobic and the hydrophilic regions will allow the formation of extended structures that are organized over multiple length scales. Our research thus seeks to systematically understand the gel phase and to exploit its features for materials synthesis.The gel mesophase is formed by adding lecithin (phosphatidylcholine) to AOT-in-isooctane reverse micelles and increasing the water content of the system. The gel is formed when the volume fractions of water and isooctane become approximately equal, and continues to be stable upon further increase of the water content. The gel is optically clear and rigid. Our objective therefore is to synthesize materials in the hydrocarbon and aqueous microphases, or to exploit the properties of an oil-water interface that is immobilized over large length scales, for interfacial synthesis, We propose the synthesis of (a) polymer and inorganic materials with extended nanostructures, (b) polymer-inorganic nanocomposites where the polymer is synthesized in the oil phase or at the oil-water interface, and the inorganic component is synthesized in the aqueous phase, and (c) polymer-polymer structured nanocomposites using hydrophobic and hydrophilic monomers. Four different examples of materials synthesis are chosen. If these can be successfully demonstrated, the conceptual framework for generating an array of other important materials will have been developed.Together with materials synthesis, we will concurrently carry out extensive studies to understand the microstructure of the gel phase and to correlate the gel microstructure with the morphology of the materials synthesized in the gel. The proposed work will use the AOT reverse micellar system as a reference point and seek to understand the transition to the gel phase. The synthesis of nanoparticles in AOT reverse micelles has been well-studied and it will be of interest to follow morphology evolution as the system follows the composition trajectory to the gel phase. Thus the research will seek to provide an understanding of how materials morphology can be systematically changed by the microstructure evolution of the templating medium.The research is a collaboration between researchers at Tulane University and the University of Rhode Island. It is anticipated that such collaboration will expose the students involved, to a broad range of scientific experimental techniques and expertise. The PIs will seek to integrate their research with education both at the graduate and at the undergraduate level.

john, Vijay/Tulane u .我们提出了一个合作项目，利用自组装表面活性剂凝胶相的潜在模板环境来开发新的纳米结构材料。凝胶的新颖之处在于它含有等量的水和油相，从而开辟了在双疏水和双亲水微环境下合成的几种可能性。我们的假设是，疏水和亲水区域的空间固定将允许在多个长度尺度上组织的扩展结构的形成。因此，我们的研究旨在系统地了解凝胶相并利用其特征进行材料合成。在aot -in-异辛烷反胶束中加入卵磷脂（磷脂酰胆碱），增加体系含水量，形成凝胶中间相。当水和异辛烷的体积分数大致相等时形成凝胶，并且在进一步增加水含量时继续保持稳定。凝胶具有光学透明和刚性。因此，我们的目标是在烃类微相和水相中合成材料，或者利用固定在大长度尺度上的油水界面的特性，用于界面合成。我们建议合成(a)具有扩展纳米结构的聚合物和无机材料，(b)聚合物-无机纳米复合材料，其中聚合物在油相或油水界面中合成，无机成分在水相中合成。(c)采用疏水和亲水单体的聚合物-聚合物结构纳米复合材料。选择了四种不同的材料合成例子。如果这些能被成功地证明，产生一系列其他重要材料的概念框架将被开发出来。与材料合成一起，我们将同时进行广泛的研究，以了解凝胶相的微观结构，并将凝胶微观结构与凝胶中合成的材料的形态联系起来。提出的工作将使用AOT反胶束系统作为参考点，并试图理解向凝胶相的过渡。纳米颗粒在AOT反胶束中的合成已经得到了很好的研究，随着体系沿着组成轨迹进入凝胶相，跟踪其形态演变将是一个有趣的研究方向。因此，该研究将寻求提供对材料形态如何通过模板介质的微观结构演变而系统地改变的理解。这项研究是杜兰大学和罗德岛大学的研究人员合作进行的。预计这种合作将使参与的学生接触到广泛的科学实验技术和专业知识。pi将寻求将他们的研究与研究生和本科教育相结合。