Collaborative Research: Surfing the order parameter - assembling nanoparticle structures through phase transitions in liquid crystal solvents

合作研究：探索有序参数——通过液晶溶剂中的相变组装纳米颗粒结构

• 批准号: 2104574
• 负责人: Linda Hirst
• 金额: $ 39.32万
• 依托单位: University of California - Merced
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-08-01 至 2024-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2104574&HistoricalAwards=false
• 关键词: Collaborative; Research; Surfing; order; parameter

Non-technical Abstract This project is focused on understanding how nanoparticles can be used to form novel structures such as capsules and foams by dispersing them in a liquid crystal. Liquid crystals are ordered fluids commonly used in LCD displays, but this project uses the liquid crystal in an unconventional way - as a solvent for nanoparticles. The novel process the team are investigating offers a rapid, scalable and largely unexploited alternative for particle assembly. They are using a custom particle design, with high-speed microscopy and new computational approaches to tune the interactions between the nanoparticles and the liquid crystal. The work plan focuses on three fundamental scientific questions: 1) How are particles transported by the fluid? 2) How does particle surface treatment control structure formation? And 3) What range of structures are possible and how are they selected? They are testing a range of particle sizes, and process and compositional parameters in a close collaboration of experiment and theory. Gaining fundamental understanding of these novel material systems will be transformative in enabling rational design of multiscale structures from simple components. The process is relevant to a wide range of applications, including encapsulation technologies in medicine, skincare, cosmetics and food science. UCM is a Hispanic Serving Institution and serves a diverse yet educationally disadvantaged part of the state. The project team is committed to mentoring students in STEM at all levels and through this collaboration numerous graduate and undergraduate students are receiving cutting-edge training to enhance their competitiveness in the workforce. Undergraduate research is an integral part of physics programs at research intensive UCM and Tufts and at SCU, a primarily undergraduate institution with a strong tradition of chemistry research. UCM is partnering with the Tufts Visiting and Early Research Scholars Experience program (VERSE) to recruit students from underrepresented groups to begin research early in their careers. Partnerships created by this project are building a strong link between three higher education institutions in both research and education. Technical Abstract This project is focused on understanding physical transport mechanisms for nanoparticles in liquid crystals and specifically how they can be leveraged to sculpt nanoparticle-based structures. The process the team investigate exploits the liquid crystal in an unconventional way, by using this anisotropic fluid as a solvent for nanoparticles and tuning interactions between these two materials. This process offers a rapid, scalable and largely unexploited alternative for particle assembly. The team is investigating this assembly process using custom particle design in a collaboration between The University of California, Merced and Santa Clara University, with high-speed fluorescence microscopy experiments at Merced and new computational approaches performed at Tufts University. The work plan focuses on three inquiry-based specific aims to be performed collaboratively 1) How are particles transported by moving phase boundaries? 2) How does particle surface treatment control structure formation? And 3) What range of structures are possible and how are they selected? This project has the potential to develop a range of novel nanoparticle-based structures, however, as well as illuminating the fundamental mechanisms governing structure selection which are still largely unknown. Gaining fundamental understanding will be transformative in enabling rational design of multiscale structures from simple components. The project has a broad scientific impact on the soft matter community and beyond by providing fundamental insights into a novel process relevant to a wide range of applications in particle transport, aggregation and nanoscience. The team takes advantage of liquid crystal’s ability to spontaneously segregate and organize nanoparticles by their chemical and/or physical properties using well known materials. A key feature of the process is that the structures (and formation mechanisms) depend only on particle size – not composition. This means that any suitably functionalized nanoparticle can be assembled – broadening the project’s impact beyond the specific aims. It should be possible to achieve similar structures in a broad range of chemical environments, opening up encapsulation technologies in medicine, skincare, cosmetics and food science. Simulation codes from this project will impact the scientific soft matter community as a resource for future investigations. These codes will be disseminated as open-source software.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

非技术摘要 该项目的重点是了解如何通过将纳米粒子分散在液晶中来形成胶囊和泡沫等新颖结构。液晶是液晶显示器中常用的有序流体，但该项目使用液晶。以一种非常规的方式——作为纳米颗粒的溶剂，该团队正在研究的新工艺为颗粒组装提供了一种快速、可扩展且很大程度上尚未开发的替代方案。该工作计划重点关注三个基本科学问题：1）粒子如何通过流体传输？2）粒子表面处理如何控制结构形成？ ）哪些结构是可能的以及如何选择它们？他们正在实验和理论的密切合作中测试一系列颗粒尺寸、工艺和成分参数，这对于实现合理的结构具有革命性的意义。多尺度结构的设计该工艺涉及广泛的应用，包括医学、护肤、化妆品和食品科学领域的封装技术。 UCM 是一家西班牙裔服务机构，致力于为该州的多元化但教育弱势群体提供服务。指导各个级别的 STEM 学生，通过这种合作，许多研究生和本科生正在接受尖端培训，以提高他们在劳动力中的竞争力。本科生研究是研究密集型 UCM 和塔夫茨大学以及 SCU 物理课程的组成部分。主要是一个UCM 与塔夫茨大学访问学者和早期研究学者体验计划 (VERSE) 合作，招募来自代表性不足的群体的学生，在他们的职业生涯早期开始研究。该项目建立的合作伙伴关系正在建立牢固的联系。三个高等教育机构在研究和教育方面的合作。 技术摘要 该项目的重点是了解液晶中纳米颗粒的物理传输机制，特别是如何利用它们来塑造基于纳米颗粒的结构。通过使用这种各向异性流体作为纳米颗粒的溶剂并调整这两种材料之间的相互作用，以一种非常规的方式制备液晶，该过程为颗粒组装提供了一种快速、可扩展且很大程度上尚未开发的替代方案。该工作计划由加州大学默塞德分校和圣克拉拉大学合作设计，在默塞德大学进行高速荧光显微镜实验，并在塔夫茨大学进行新的计算方法，重点关注三个基于探究的具体目标：合作进行 1) 颗粒如何通过移动相边界进行传输？ 2) 颗粒表面处理如何控制结构形成？ 3) 该项目有潜力开发一系列结构？然而，基于纳米粒子的新型结构，以及阐明仍然在很大程度上未知的控制结构选择的基本机制，对于从简单的组件进行多尺度结构的合理设计将具有革命性的意义。软物质社区及其他领域提供该团队利用液晶通过众所周知的材料的化学和/或物理特性自发分离和组织纳米颗粒的能力，对与颗粒传输、聚集和纳米科学领域的广泛应用相关的新颖过程进行了基本见解。该过程的特点是结构（和形成机制）仅取决于颗粒尺寸，而不是组成，这意味着可以组装任何适当功能化的纳米颗粒，从而扩大该项目的影响，超越特定目标。应该有可能实现类似的结构。在广泛的化学环境中，开放医学、护肤、化妆品和食品科学中的封装技术将影响科学软物质社区，作为未来研究的资源。这些代码将作为开源进行传播。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。