Elasticity, Deformation, Rearrangement & Assembly in Complex Fluids

弹性、变形、重排

• 批准号: 1607378
• 负责人: Arjun Yodh
• 金额: $ 42.96万
• 依托单位: University of Pennsylvania
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-09-01 至 2020-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1607378&HistoricalAwards=false
• 关键词: Elasticity; Deformation; Rearrangement; Assembly; Complex

Non-technical AbstractThe proposed experimental research will have impact in two major science and technology arenas: how to make a tougher material and how to adapt ideas of liquid crystal display technology to new water-based liquid crystal systems. Broadly, the program develops new ability to formulate and manipulate micro- and nano-particles and macromolecules in solution. Thus the research enhances the science and technology enterprise that underpins applications efforts for US industries involved with sensing/actuation, microfluidics, drug delivery, photonics, printing, coatings, cosmetics and agriculture. The program will train a new generation of scientists and engineers in soft materials, formulation, advanced optical microscopy, electro-optics, microfluidics, rheology & computation. After finishing, PhD students & post-docs enter the work force and strengthen US technological and economic infrastructure; furthermore, a diverse group of undergraduate and high school participants are typically stimulated every summer in our laboratory to pursue STEM education/career choices.Technical AbstractThe proposed program aims to advance knowledge about complex fluids and soft materials, but many findings will also interest the hard condensed matter, chemical engineering and materials science communities. The proposed experiments are unified by their focus on micro-mechanics, broadly defined. One set will measure structural and dynamical properties of colloidal glasses and crystals with goals to identify regions within these materials that are "soft" and exhibit increased propensity to deform or rearrange. A second set will investigate lyotropic chromonic liquid crystals. These liquid crystals are unusual in that they twist very easily which leads to formation of chiral structures from achiral mesogens, they exhibit two levels of assembly hierarchy from molecules to rod-mesogens to LC phases, and they are water soluble. The consequences of these properties will be probed by diffusion experiments which track motions of particles dressed by local LC director fields, by study of the competition between elastic energy and molecular assembly hierarchy in "extreme" confined geometries, and in novel "drying" of multi-phase droplets. Collectively, the experiments use advanced optical microscopies, light scattering and rheometry for sample observation, and they require formulation of novel soft materials via controlled suspension chemistry and physics, microfluidics, etc. For example, colloidal particles with different shapes, interactions and potential for in-situ manipulation are/will-be developed.

非技术摘要提出的实验研究将在两个主要的科学和技术领域影响：如何制作更艰难的材料以及如何将液晶显示技术的思想适应新的水基液晶系统。从广义上讲，该程序开发了新的能力，可以在溶液中制定和操纵微分子和大分子。因此，这项研究增强了科学和技术企业的基础，该企业为与感应/促进，微流体，药物输送，光子学，印刷，涂料，化妆品和农业有关的美国行业的应用工作提供了努力。该计划将培训新一代的科学家和工程师，以软材料，配方，先进的光学显微镜，电气镜，微流体，流变和计算。完成后，博士生和博士后进入劳动力并加强了美国技术和经济基础设施；此外，在我们实验室中，通常会在每年夏天刺激一组多样化的本科和高中参与者，以寻求STEM教育/职业选择。技术摘要旨在提出的计划旨在提高人们对复杂的液体和软材料的了解，但许多发现也将使硬冷凝物质，化学工程和材料科学科学社区感兴趣。提出的实验是通过对微型力学的关注来统一的，广泛定义。一组将测量胶体玻璃和晶体的结构和动力学特性，其目标是识别“软”材料中的区域，并表现出更大的变形或重新排列的倾向。第二组将研究溶式染色体液体晶体。这些液晶很不寻常，因为它们很容易扭曲，从而导致摄制剂的手性结构形成，它们表现出两个级别的组装层次结构，从分子到棒状胶质成分，再到LC相，并且是水溶性的。这些性质的后果将通过扩散实验来探测，这些实验通过研究弹性能量与分子组装层次结构之间的竞争在“极端”限制的几何形状以及多阶段液滴的新颖“干燥”中，跟踪局部LC导演场的颗粒运动。总的来说，实验使用了先进的光学显微镜，光散射和流变特征进行样品观察，并且需要通过受控的悬架化学和物理学，微流体，微流体等来制定新型软材料。