Dynamics of Stratification in Multicomponent Colloidal Films During Evaporative Drying

蒸发干燥过程中多组分胶体膜的分层动力学

• 批准号: 1903189
• 负责人: Surita Bhatia
• 金额: $ 34.79万
• 依托单位: SUNY at Stony Brook
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-06-01 至 2024-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1903189&HistoricalAwards=false
• 关键词: Dynamics; Stratification; Multicomponent; Colloidal; Films

Nanoparticle films have wide applications, including antibacterial paints, corrosion-resistant coatings, and battery separator membranes. Often, the locations of certain components in the film must be carefully controlled. This has traditionally been achieved with expensive multi-step fabrication processes. Recent mathematical models of nanoparticle film formation have identified a means to create complex, vertically-structured coatings in a single step, a process referred to as stratification. This process has the potential to decrease production time and costs of multifunctional nanoparticle films. However, there are few experimental studies of the stratification process. In this project, a new experimental technique that involves scanning through the film with a narrowly-focused X-ray beam will be performed during the stratification process. These experiments will follow motion of particles throughout the film formation process, and will ultimately provide information on how stratification depends on the nanoparticle concentration, nanoparticle size, evaporation rate, and other processing parameters. The research will help improve manufacturing processes for multicomponent films used in applications that will benefit human welfare and health, such as inorganic-polymer films for next-generation batteries, drug-loaded coatings for medical implants, and mold-resistant paints for humid environments. Impacts related to STEM workforce development include training of a graduate student and undergraduate students in novel experimental techniques for colloidal materials. The investigator will also aim to recruit students from underrepresented populations for the research. Finally, concepts from the research will be incorporated into new curriculum materials and video lectures on fluid mechanics for high school audiences. Recent research has identified a means to create vertically-structured coatings in a single step during stratification. Theoretical descriptions of binary colloidal mixtures show a variety of stratification regimes as the volume fraction and Peclet number of small and large particles are varied. However, comprehensive comparison of model predictions with experiments has not yet been achieved because of difficulties in (i) quantifying the vertical concentration profile of particles in the film, and (ii) following motion of particles during the film formation process. This project will use small-angle X-ray scattering (SAXS) with a narrowly-focused beam, performed at varying vertical positions in the film, to fully explore the complex stratification behavior predicted by recent models. The objectives of the work are to: (1) create an experimental process diagram of stratification behavior as a function of particle volume fraction and Peclet number; (2) conduct the first measurements of stratification during film formation by performing time-resolved microbeam SAXS; (3) conduct X-ray photon correlation spectroscopy (XPCS) studies to yield knowledge of how particle diffusivity and dynamics vary during film formation; and (4) integrate research into new curricular materials and video lectures on fluid mechanics for high school audiences. The work will provide the first in situ measurements of particle concentration during film formation in multicomponent systems and the first direct experimental test of recent stratification models in both final dried films and during the film formation process. The project will also help establish new advanced scattering techniques for characterization of colloidal materials. Finally, the data and insight gained will aid in driving improvements to theoretical descriptions of stratification. The research will broadly impact development of single-step processes to create multicomponent films with complex concentration profiles, decreasing production time and costs of multifunctional films.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.

纳米粒子膜具有广泛的应用，包括抗菌涂料、耐腐蚀涂料和电池隔膜。通常，胶片中某些成分的位置必须仔细控制。传统上，这是通过昂贵的多步骤制造工艺实现的。最近纳米颗粒薄膜形成的数学模型已经确定了一种在单一步骤中产生复杂的、垂直结构的涂层的方法，这一过程被称为分层。这一工艺有可能减少多功能纳米颗粒薄膜的生产时间和成本。然而，关于层化过程的实验研究很少。在这个项目中，一种新的实验技术将在分层过程中进行，该技术涉及到用窄聚焦X射线束扫描薄膜。这些实验将跟踪颗粒在整个成膜过程中的运动，并最终提供分层如何依赖于纳米颗粒浓度、纳米颗粒大小、蒸发速率和其他工艺参数的信息。这项研究将有助于改进多组分薄膜的制造工艺，这些薄膜用于有益于人类福利和健康的应用，如用于下一代电池的无机聚合物薄膜，用于医疗植入物的载药涂层，以及用于潮湿环境的防霉涂料。与STEM劳动力发展相关的影响包括对研究生和本科生进行胶体材料新实验技术的培训。这位研究人员还将致力于从代表性不足的人群中招募学生进行研究。最后，这项研究的概念将被纳入新的课程材料和面向高中观众的流体力学视频讲座。最近的研究已经确定了一种在分层过程中一步产生垂直结构涂层的方法。二元胶体混合物的理论描述表明，随着小颗粒和大颗粒的体积分数和Peclet数的不同，分层机制也不同。然而，由于(I)定量膜中颗粒的垂直浓度分布和(Ii)膜形成过程中颗粒的跟踪运动的困难，尚未实现模型预测与实验的全面比较。该项目将使用小角X射线散射(SAXS)和窄聚焦光束，在胶片中的不同垂直位置执行，以充分探索最近模型预测的复杂分层行为。这项工作的目标是：(1)制作随着颗粒体积分数和Peclet数变化的分层行为的实验流程图；(2)通过时间分辨微束SAXS对成膜过程中的分层进行首次测量；(3)进行X射线光子相关光谱(XPCS)研究，以了解颗粒在成膜过程中的扩散性和动力学变化；以及(4)将研究纳入新的课程材料，并为高中观众举办流体力学视频讲座。这项工作将首次在多组分系统中对成膜过程中的颗粒浓度进行现场测量，并首次在最终干燥膜和成膜过程中对最新的分层模型进行直接实验测试。该项目还将帮助建立新的先进散射技术，用于表征胶体材料。最后，获得的数据和洞察力将有助于推动分层理论描述的改进。这项研究将广泛影响一步法工艺的发展，以创造具有复杂浓度分布的多组分薄膜，减少多功能薄膜的制作时间和成本。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

Dual‐Scale Nanostructures via Evaporative Assembly

• DOI: 10.1002/admi.201901954
• 发表时间: 2020-02
• 期刊: Advanced Materials Interfaces
• 影响因子: 5.4
• 作者: S. Srivastava;Zaibudeen A. Wahith;O. Gang;C. Colosqui;S. Bhatia

Dynamics and microrheology of colloidal clay-polymer glasses and gels: Size-dependent phenomena and re-entrant behavior at early aging times

胶体粘土聚合物玻璃和凝胶的动力学和微流变学：早期老化时的尺寸依赖性现象和重入行为

• DOI: 10.1063/5.0130816
• 发表时间: 2023
• 期刊: The Journal of Chemical Physics
• 作者: Shen, Jiachun;Bhatia, Surita R.
• 通讯作者: Bhatia, Surita R.

Collective Nanoparticle Dynamics Associated with Bridging Network Formation in Model Polymer Nanocomposites

与模型聚合物纳米复合材料中桥接网络形成相关的集体纳米粒子动力学

• DOI: 10.1021/acsnano.1c01283
• 发表时间: 2021
• 期刊: ACS Nano
• 影响因子: 17.1
• 作者: Yavitt, Benjamin M.;Salatto, Daniel;Zhou, Yuxing;Huang, Zhixing;Endoh, Maya;Wiegart, Lutz;Bocharova, Vera;Ribbe, Alexander E.;Sokolov, Alexei P.;Schweizer, Kenneth S.
• 通讯作者: Schweizer, Kenneth S.

Mapping graphene layer number at few-micron-scale spatial resolution over large areas using laser scanning

• DOI: 10.1088/2053-1583/abcbe7
• 发表时间: 2020-11
• 期刊: 2D Materials
• 影响因子: 5.5
• 作者: A. Carr;Daniel DeGennaro;J. A. Andrade;Alexander Barrett;S. Bhatia;M. Eisaman

Microstructure, microrheology, and dynamics of laponite® and laponite®-poly(ethylene oxide) glasses and dispersions

• DOI: 10.1007/s00397-020-01210-y
• 发表时间: 2020-04
• 期刊: Rheologica Acta
• 影响因子: 2.3
• 作者: Bingqian Zheng;James R Breton;R. S. Patel;S. Bhatia