Structure and Dynamics of Composite, Fluid Interfaces

复合材料、流体界面的结构和动力学

• 批准号: 0331737
• 负责人: Gerald Fuller
• 金额: $ 30万
• 依托单位: Stanford University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-01-01 至 2006-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0331737&HistoricalAwards=false
• 关键词: Structure; Dynamics; Composite; Fluid; Interfaces

The proposed research will investigate the dynamics and structure of composite, fluid interfaces comprised of combinations of colloidal particles and molecular amphiphiles. Two-dimensional suspensions of asymmetric particles will also be studied. Since many commercial and naturally occurring systems (emulsions, foams, and the alveoli in our lungs) are complex mixtures of amphiphilic materials, fundamental understanding of their interfacial rheology is central to advancing the performance of products and treatment procedures.This work, which is primarily experimental, will take advantage of new measurement methods developed in our laboratory (interfacial rheometry, interfacial flow-microscopy) to reveal the relationship between interfacial microstructure and interfacial rheology. This work will focus on mobile interfaces comprised of colloidal particles that coexist with molecular amphiphiles. This results in two-dimensional suspensions that are expected to have a unique rheological character. In addition to spherical, colloidal particles, prolate and oblate particles will be studied since these systems offer the possibility of mimicking fatty acids and alcohols where positional and orientational order come together to create complex 2D phase diagrams. Intellectual merit. Complex fluid interfaces can be classified in ways that are similar to their complex fluid counterparts (2D melts, solutions, suspensions, etc.). Indeed, restricting molecules and particles to two dimensions often increases rheological nonlinearities. Most physical systems, however, are mixtures of amphiphilic constituents, but little attention has been offered in this direction. The experiments planned here will provide the first systematic data on two-dimensional suspensions where particles are collected within monolayers on nonNewtonian, molecular amphiphiles.Broader impacts. The interfacial rheology of complex, composite monolayers is important to many commercial activities, such as the processing of food products and personal products.These systems are often in the form of emulsions and foams that require stabilization. Furthermore, colloidal systems are useful model systems for the study of basic physical phenomena and in this case two-dimensional monolayers comprised of asymmetric particles will be used to mimic the rich phase behavior of fatty acids and phospholipids.

拟议的研究将调查的动力学和结构的复合材料，流体界面组成的胶体颗粒和分子两亲物的组合。 还将研究不对称颗粒的二维悬浮液。由于许多商业和自然发生的系统（乳液、泡沫和我们肺部的肺泡）是两亲性材料的复杂混合物，对其界面流变学的基本理解对于提高产品性能和处理程序至关重要。这项工作主要是实验性的，将利用我们实验室开发的新测量方法。（界面流变仪、界面流动显微镜）来揭示界面微观结构与界面流变性之间的关系。这项工作将集中在移动的界面组成的胶体颗粒共存的分子两亲物。这导致预期具有独特流变特性的二维悬浮液。除了球形，胶体颗粒，扁长形和扁圆形颗粒将进行研究，因为这些系统提供了模仿脂肪酸和醇的位置和取向顺序走到一起，创造复杂的二维相图的可能性。智力上的优点。复杂流体界面可以按照与其复杂流体对应物（2D熔体、溶液、悬浮液等）类似的方式进行分类。事实上，将分子和颗粒限制在二维通常会增加流变非线性。然而，大多数物理系统是两亲组分的混合物，但很少有人注意到这一点。这里计划的实验将提供第一个二维悬浮液的系统数据，其中颗粒被收集在非牛顿分子两亲物的单层内。复杂复合单分子膜的界面流变性对许多商业活动都很重要，例如食品和个人用品的加工。这些体系通常是需要稳定的乳液和泡沫形式。此外，胶体系统是研究基本物理现象的有用模型系统，在这种情况下，由不对称颗粒组成的二维单层将用于模拟脂肪酸和磷脂的富相行为。