EAGER: CAS-MNP: Mapping the structure–property relationships of micro- and nanoplastics by in-situ nanoscopic imaging and simulation

EAGER：CAS-MNP：通过原位纳米成像和模拟绘制微米和纳米塑料的结构与性能关系

• 批准号: 2034496
• 负责人: Qian Chen
• 金额: $ 30万
• 依托单位: University of Illinois at Urbana-Champaign
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-08-01 至 2022-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2034496&HistoricalAwards=false
• 关键词: EAGER; CAS; MNP; Mapping; structure

NON-TECHNICAL SUMMARY:This collaborative project combines experiments and simulation to understand micro- and nanoplastics, which are tiny pieces of plastics invisible to human eyes that have been shown to be ubiquitously present in the food chain and the environment. Micro- and nanoplatics thus pose major concerns on their unpredictable impact on human health, ecosystem, and food. For example, micro-plastics, the larger-sized population of the plastic pieces, are found in freshwaters, saltwater fish, and air, at high concentrations and in various shapes such as fragments, foam, and pellets. Nanoplastics (smaller than 100 nanometers are found in water and could be particularly worrisome for human health because their sizes fall into a regime of small grains that living cells could incorporate. Micro- and nanoplastics cannot be thoroughly examined using the conventional toolkits based on statistical averaging. It is for these reasons that the research goal of this proposal is to introduce and use liquid-phase transmission electron microscopy (TEM). This will enclose a nano-aquarium with water containing micro- and nanoplastics to record movies of their motion, interactions, and aggregation on the fly, and then be correlated with theory to inform predictive modeling. The fundamental understanding to be obtained is relevant to sustainability (e.g., upcycling of plastics by separating, harvesting, and recycling of micro- and nanoplastics) and may apply to other systems such as geological grains (sands, clays). In addition to interdisciplinary student training, the educational goal of this project is to provide previously inaccessible experimental and modeling data to the scientific community that could potentially be applied to different micro- and nanoplastics in other geographic regions. "Plastics in water" demonstrations and lectures will be developed for outreach to K-12 students and the general public. The diverse team of three co-PIs will also actively encourage women and minorities to pursue scientific careers.TECHNICAL SUMMARY:The research goal of this experimental‒simulation collaboration is to understand the fundamental relationships among the structure (e.g., composition, size, shape), colloidal interactions, and aggregation dynamics of micro- and nanoplastics in water or in the presence of separation membranes at unprecedented nanometer resolution, thereby enabling efficient strategies to minimize the footprint of micro- and nanoplastics in the ecosystem. The generic irregularity and high dispersity of such plastic particles has resulted in a knowledge gap in understanding the principles of how structure encodes their properties and phase behaviors (such as flocculation into large aggregates or heavy sediments) which needs to be bridged in order to facilitate their removal. This research project aims to fill this gap through an integrated effort of polymer synthesis and characterization, nanoimaging and colloid simulation. New understanding will be obtained by using the special microscopy suite of low-dose liquid-phase transmission electron microscopy (TEM) and scanning transmission electron microscopy (STEM) to image the micro- and nanoplastics in liquids at nanometer and millisecond resolutions in real time. Starting with (i) mapping the nanoscale structures of model and real-life micro- and nanoplastics and how the structures relate with the intercolloidal interaction potential on the single particle and pairwise level, this project will continue with (ii) elucidating how the interaction potential affects the aggregation dynamics of micro- and nanoplastics. It will ultimately be followed by (iii) investigating the effects of environmental variations of practical relevance on structure and phase behaviors, especially in the presence of separation membranes so as to understand the fundamental adsorption and penetration dynamics..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：这个协作项目结合了实验和模拟，以了解微塑料和纳米塑料，这些塑料是人眼看不见的微小塑料，这些塑料被证明是在食物链和环境中无处不在的。因此，微型塑料对它们对人类健康，生态系统和食品的不可预测影响提出了重大关注。例如，在淡水，盐水鱼和空气中，以高浓度和各种形状（例如碎片，泡沫和颗粒）中发现了微型塑料，大小的塑料碎片种群。纳米塑料（在水中发现了小于100纳米，可能对人类健康特别担心，因为它们的尺寸属于活细胞可能会掺入的小谷物方案。微型和纳米塑料无法使用基于统计的常规工具来彻底检查基于统计平均的常规工具kit，因此该建议的研究目标是介绍了液体液体，而是将其用于液体液体液位。纳米 - 占水的纳米质量，含有微塑料和纳米塑料，以录制其运动，相互作用和聚集的电影，然后与理论相关，以告知预测性建模，与可持续性相关。地质谷物（沙子，粘土）除了跨学科的学生培训外，该项目的教育目标是向科学界提供以前无法访问的实验和建模数据，这些数据可能会应用于其他地理位置的不同微塑料。将向K-12学生和公众开发“水中的塑料”演示和讲座。三个共同案件的潜水团队还将积极鼓励妇女和少数群体从事科学职业。技术摘要：实验性塑料协作的研究目标是了解结构之间的基本关系（例如，组成，大小，大小），胶体互动，胶体互动以及在微型和纳米塑料中的分离机制，在水或纳米层中的聚集动力学，并在水上分离范围内，并在水上造成了何种情况下的水平机制，以下是在水上或纳米层次的范围。从而实现有效的策略，以最大程度地减少生态系统中微塑料和纳米塑料的足迹。这种塑料颗粒的通用不规则性和高度分散已导致知识差距在理解结构如何编码其性质和相行为的原理（例如絮凝成大骨料或重型沉积物中），需要弥合，以促进其移走。该研究项目旨在通过聚合物合成和表征，纳米影像和胶体模拟的综合工作来填补这一空白。将通过使用低剂量液相透射电子显微镜（TEM）和扫描透射电子显微镜（STEM）的特殊显微镜套件来获得新的理解，以实时在纳米和毫秒决议下对液体中的微塑料和纳米塑料进行成像。从（i）映射模型以及现实生活的微塑料和纳米塑料的纳米级结构以及该结构与单个粒子和成对水平上的固定相互作用潜力之间的关系，该项目将继续（iii）阐明互动如何影响微塑料和纳米塑料的互动电位。 It will ultimately be followed by (iii) investigating the effects of environmental variations of practical relevance on structure and phase behaviors, especially in the presence of separation mechanisms so as to understand the fundamental adsorption and penetration dynamics..This award reflects NSF's statutory mission and has been deemed precious of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.