Polymer Nanocomposites using Discrete Nanoparticles and Bicontinuous Scaffolds: New Strategies for Connective Morphologies and Property Control

使用离散纳米粒子和双连续支架的聚合物纳米复合材料：连接形态和性能控制的新策略

• 批准号: 2407300
• 负责人: Russell Composto
• 金额: $ 51万
• 依托单位: University of Pennsylvania
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2024
• 资助国家: 美国
• 起止时间: 2024-09-01 至 2027-08-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2407300&HistoricalAwards=false
• 关键词: Polymer; Nanocomposites; using; Discrete; Nanoparticles

NON-TECHNICAL SUMMARY:Polymer nanocomposites are mixtures of flexible long-chain molecules (polymers) and hard functional particles. Although found in everyday materials from tires to paints, polymer nanocomposites also have future potential as advanced functional materials in applications from energy storage to water purification. This research will provide a fundamental understanding of chemistry, physics and engineering principles that can be brought together to investigate a new type of composite containing a mixture of charged polymers and particles coated with similar or different charged polymers to achieve properties not possible with traditional composites. In short, the overall goal is to promote the progress of science leading to new and improved advanced materials. One fundamental issue is controlling molecular interactions that determine how particles are distributed in a composite material. One challenge with this “mixing” approach is a tendency for particles to aggregate. To overcome this limitation, a second fundamental issue in this study is the fabrication of highly loaded composites where the polymer is incorporated into a scaffold, analogous to water swelling a sponge. To accelerate the discovery of new materials, a smart experimental approach will be used where data will be characterized and fed back immediately to formulate a new composite. This process is continued until the optimum formulation is found. Students performing this research will gain valuable skills in data science, enhancing career opportunities, and learn to utilize valuable resources (materials, equipment) sustainably. Graduate and undergraduate students also participate in annual public events including Nanotechnology Day at Penn, Philly Materials Day, and the Philadelphia Science Festival. A particularly unique program is “First Exposure to Research in STEM,” which provides a structure for introducing first-generation, low-income students to their first research project. TECHNICAL SUMMARY:Polymer nanocomposite (PNC) structure determines their properties. However, the full potential of PNCs is hindered by lack of control over structure-property relationships, partly due to the prevalence of non-equilibrium structures. Here, PNCs containing discrete nanoparticles (NP) in a polymer matrix or those fabricated from bicontinuous, nanoporous scaffolds are designed, processed and characterized to understand their fundamental thermodynamic, interfacial, and dynamic principles. The objectives of this work are to (1) elucidate how brush charge density affects NP dispersion in polyelectrolyte (PE) matrices of varying charge and polarity and explore kinetic pathways towards percolated structures, (2) investigate infiltration kinetics of polar polymers into scaffolds, and (3) develop autonomous experimentation (AE) to accelerate discovery of PNCs with distinct structures. Aim 1 investigates PE-NPs in polymer matrices of increasing polarity. Aim 1a studies PE-NP/matrix miscibility to provide insight into brush-matrix electrostatic interactions. Aim 1b studies phase separation to guide the identification of kinetic pathways that produce percolation of charged brushes. Aims 2a and 2b investigate bicontinuous metal and polymer scaffolds, respectively, infiltrated with polar matrix polymers. Infiltration kinetics and properties are studied as a function of pore confinement and scaffold type. The significance of these studies involves the discovery of pathways for fabricating (bi)continuous structures for enhanced energy storage or water purification applications. In Aim 3, AE-optical microscopy will be used to map the phase diagram of PNCs, whereas AE-GISAXS, in collaboration with scientists from Brookhaven National Laboratory, will identify materials and processing conditions that produce percolated PNC structures with advantageous mechanical properties and conductivity. In summary, fundamental studies of PNCs) combined with data-science-driven characterization will act synergistically to advance knowledge for materials discovery in this project..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.

非技术综述：聚合物纳米复合材料是柔性长链分子(聚合物)和硬功能粒子的混合物。虽然聚合物纳米复合材料存在于从轮胎到涂料的日常材料中，但在从储能到净水的应用中，聚合物纳米复合材料也具有作为先进功能材料的未来潜力。这项研究将提供对化学、物理和工程原理的基本理解，这些原理可以结合在一起来研究一种新型复合材料，该复合材料包含带电聚合物和涂有相似或不同带电聚合物的颗粒的混合物，以实现传统复合材料无法实现的性能。简而言之，总体目标是促进科学进步，导致新的和改进的先进材料。一个根本的问题是控制分子相互作用，这种相互作用决定了颗粒在复合材料中的分布方式。这种“混合”方法的一个挑战是粒子聚集的趋势。为了克服这一限制，本研究的第二个基本问题是制造高负载复合材料，其中聚合物被结合到支架中，类似于海绵的水膨胀。为了加速新材料的发现，将使用一种智能的实验方法，数据将被表征并立即反馈以配制新的复合材料。这一过程一直持续到找到最佳配方为止。从事这项研究的学生将获得宝贵的数据科学技能，增加就业机会，并学习可持续地利用有价值的资源(材料、设备)。研究生和本科生还参加一年一度的公共活动，包括宾夕法尼亚大学的纳米技术日、费城材料日和费城科学节。一个特别独特的项目是“STEM研究的第一次接触”，它为第一代低收入学生介绍他们的第一个研究项目提供了一个结构。技术综述：聚合物纳米复合材料(PNC)的结构决定其性能。然而，由于缺乏对结构-性质关系的控制，PNC的全部潜力受到阻碍，部分原因是非平衡结构的普遍存在。在这里，我们设计、加工和表征了聚合物基质中含有离散纳米颗粒(NP)的PNC或由双连续纳米孔支架制成的PNC，以了解它们的基本热力学、界面和动力学原理。这项工作的目的是(1)阐明刷子电荷密度如何影响NP在不同电荷和极性的聚电解质(PE)基质中的分散，并探索通向渗流结构的动力学途径；(2)研究极性聚合物在支架中的渗透动力学；(3)发展自主实验(AE)以加速发现具有不同结构的PNC。目的1研究增极性聚合物基质中的PE-NPs。目的1a研究PE-NP/基质的相容性，为深入了解刷子-基质的静电相互作用提供依据。目的1b研究相分离以指导识别产生带电刷子渗流的动力学途径。目标2a和2b分别研究用极性基质聚合物渗透的双连续金属和聚合物支架。研究了孔约束和支架类型对渗透动力学和渗透特性的影响。这些研究的意义包括发现用于增强能量存储或水净化应用的(双)连续结构的制造路径。在目标3中，将使用声发射光学显微镜绘制PNC的相图，而AE-GISAXS将与布鲁克海文国家实验室的科学家合作，识别产生具有有利机械性能和导电性的渗透PNC结构的材料和工艺条件。总而言之，对PNC的基础研究)与数据科学驱动的表征相结合，将协同推进该项目中材料发现的知识。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。