Interactions and Self-Assembly of Particles in Complex Fluids

复杂流体中颗粒的相互作用和自组装

• 批准号: 0204199
• 负责人: Venkat Ganesan
• 金额: $ 24万
• 依托单位: University of Texas at Austin
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-07-01 至 2006-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0204199&HistoricalAwards=false
• 关键词: Interactions; Self; Assembly; Particles; Complex

This award supports theoretical and computational research on complex fluids. The PI aims to combine field-theoretic and particle-based approaches to develop hybrid simulation tools that can be used to study the thermodynamics and self-assembly of particles in complex fluids. These hybrid techniques can account for the disparate length scales accompanying particle dispersions in complex fluid media, while efficiently incorporating steric and short-range interactions. Two classes of studies and tools are proposed: (1) Field-Theoretic Simulations (FTS), an approach recently developed by the PI, will be used to systematically evaluate the interactions between particles of arbitrary geometries in different complex fluids. The results may yield fundamental insights into the different factors that influence fluctuation-induced forces, in particular, their nonpairwise additive nature, as well as the interplay between energetic (arising from a physical interaction between the complex fluid and the surface of the particle) and entropic interactions. The results from these studies will also be used in effecting an in vacuo simulation of the particles, in order to glean insights into the self-assembly features of the particles. (2) The PI will develop a hybrid multibody simulation approach to the self-assembly of particles in complex fluids. A combination of FTS and mean-field equations for the fields at every step determines the effective interactions between the rigid units. These effective interactions will be used to "evolve" the rigid units through a particle-based simulation. The studies are aimed to clarify the role of multibody interactions, nonpairwise additivity of forces and excluded volume interactions in modulating the self-assembly of a variety of mixtures of complex fluids and particles. The research will be effected in the context of studies of the interactions and self-assembly in polymer-particle mixtures, charge stabilized colloidal dispersions, and multiblock rod-coil copolymers. These are ideal model systems in which to study effects pertaining to fluctuations, self-assembly, and dynamics. Each of these can be tuned independently and in a controlled way by tailoring the synthesis conditions. This capability allows for a synergistic interaction with experimental studies to compare predictions and experiments. In each of these model systems, the PI plans to carry out studies, linked by a common objective, to discern the self-assembly arising from a competition between steric and energetic interactions, as well as the interplay between nematic/smectic ordering, crystallization and microphase separation.The successful implementation of these hybrid simulation approaches is expected to have significant impact on the development of multiscale computational approaches to the design of advanced materials.%%%This award supports theoretical and computational research and education on complex fluids. The PI aims to combine distinct and powerful computational approaches to develop hybrid simulation tools that can be used to study the thermodynamics and self-assembly of particles in complex fluids. These tools will be used to study the interactions and self-assembly in polymer-particle mixtures, charge stabilized colloidal dispersions, and multiblock rod-coil polymers to elucidate important issues in the physics of complex fluids. The simulation tools also contribute to efforts to use theoretical methodology to predict the morphological characteristics and properties of advanced materials that result from specific molecular parameters. ***

该奖项支持复杂流体的理论和计算研究。该 PI 旨在结合场论和基于粒子的方法来开发混合模拟工具，可用于研究复杂流体中粒子的热力学和自组装。这些混合技术可以解释复杂流体介质中颗粒分散所伴随的不同长度尺度，同时有效地结合空间和短程相互作用。提出了两类研究和工具：（1）场论模拟（FTS），这是PI最近开发的一种方法，将用于系统地评估不同复杂流体中任意几何形状的粒子之间的相互作用。这些结果可能会对影响波动引起的力的不同因素产生基本的见解，特别是它们的非成对相加性质，以及能量（由复杂流体和粒子表面之间的物理相互作用产生）和能量之间的相互作用。熵相互作用。这些研究的结果还将用于对粒子进行真空模拟，以深入了解粒子的自组装特征。 (2) PI 将开发一种混合多体模拟方法，用于复杂流体中颗粒的自组装。每一步场的 FTS 和平均场方程的组合决定了刚性单元之间的有效相互作用。这些有效的相互作用将用于通过基于粒子的模拟“进化”刚性单元。 这些研究旨在阐明多体相互作用、力的非成对相加性和排除体积相互作用在调节各种复杂流体和颗粒混合物的自组装中的作用。该研究将在聚合物颗粒混合物、电荷稳定胶体分散体和多嵌段棒-线圈共聚物中的相互作用和自组装的研究背景下进行。这些是研究波动、自组装和动力学效应的理想模型系统。其中每一个都可以通过定制合成条件以受控方式独立调整。此功能允许与实验研究进行协同交互，以比较预测和实验。在每个模型系统中，PI 计划开展由共同目标联系起来的研究，以辨别空间相互作用和能量相互作用之间的竞争所产生的自组装，以及向列/近晶有序、结晶和相互作用之间的相互作用。这些混合模拟方法的成功实施预计将对先进材料设计的多尺度计算方法的发展产生重大影响。%%%该奖项支持复杂流体的理论和计算研究及教育。该 PI 旨在结合独特且强大的计算方法来开发混合模拟工具，可用于研究复杂流体中颗粒的热力学和自组装。这些工具将用于研究聚合物颗粒混合物、电荷稳定胶体分散体和多嵌段棒线圈聚合物中的相互作用和自组装，以阐明复杂流体物理学中的重要问题。模拟工具还有助于使用理论方法来预测由特定分子参数产生的先进材料的形态特征和性能。 ***