Polymer Physics Across Scales: Bridging Atomistic and Coarse-Grained Polymer Models

非技术总结本研究项目旨在开发理论和计算方法来模拟从单个分子到整体材料的各种长度尺度的软聚合物材料。聚合物材料在我们的日常生活中无处不在，它们在几乎每个技术领域都扮演着重要的角色。目前对软聚合材料行为的预测框架可以分为两种不同的哲学方法。第一种是基于精确到原子级别的详细模型；对于彻底发现聚合材料来说，这些模型通常在计算上很难处理。第二种更易于计算的方法是基于聚合物的低分辨率表示，从中可以做出物理行为的一般预测，但代价是分子水平的细节。这一研究项目的目的是建立一个路线图，在这些不同的视角之间架起桥梁，利用每种方法的优势，同时避免各自的缺点。其目标是能够研究以前不可能捕捉到的聚合物材料的广泛性质。这一研究项目还为培训理论家和计算科学家提供了一个平台，他们将能够解决软材料中的各种基本和应用问题。该项目的研究和教育目标得到了通过开发名为LABScI的动态方案的更广泛宣传的补充。扩大科学教学的实验室活动。该计划为正在接受儿童癌症和其他疾病治疗的高中生开发和实施实验室科学和工程学教学模块。这项计划是在露西尔·帕卡德儿童医院的医院学校试行的，斯坦福大学的本科生和研究生参与了这项计划的开发。正在进行的努力旨在将这一计划作为医院-学校教育的普通实验室科学课程在全国范围内广泛传播。为了实现这一目标，该项目将开发视频和在线教具，进一步推动实验室的实施。技术总结本研究项目旨在开发理论和计算方法来模拟从单个分子到整体材料的各种长度尺度的软聚合物材料。目前对聚合物材料的理解主要是基于粗粒模型，但高性能计算模拟的发展提供了新的粒状细节，这对材料的开发将是无价的。弥合这些尺度是软材料物理学的一个标志性问题。PI的目标是系统地结合不同级别的细节，以捕捉聚合物材料的多尺度行为。这项研究计划中的基础性工作将为聚合物材料的介观行为提供新的和关键的见解，这是许多材料现象的关键长度尺度，用于技术应用。该项目旨在解决软材料自组装和热力学行为方面的关键问题，这些问题需要通过确定一个中等尺度的物理模型来弥合这些不同的观点，该模型服从理论分析，同时包含足够的颗粒细节以与详细模型进行比较。半柔性聚合物的定义是具有连接这两个角度的细节水平，描述此类材料的统计行为的基础工作是这一理论工作的关键投入。该研究项目通过(1)建立预测半柔性聚合物热力学行为的软件包，(2)预测半柔性聚合物材料的结构和液晶有序性的影响，以及(3)确定聚合物和溶剂有序性对聚电解质材料相行为的影响，来研究半柔性聚合物溶液和材料的物理行为。这些关键的探索领域提供了可交付的工具和结果，这些工具和结果直接与软材料的现有理论、计算和实验方法相结合。这一努力也可能为颗粒分子相互作用如何影响软聚合物材料中的介观行为提供新的线索。这一研究项目还为培训能够解决软材料中各种基本和应用问题的理论家和计算科学家提供了一个平台。该项目的研究和教育目标得到了通过开发名为LABScI的动态方案的更广泛宣传的补充。扩大科学教学的实验室活动。该计划为正在接受儿童癌症和其他疾病治疗的高中生开发和实施实验室科学和工程学教学模块。这项计划是在露西尔·帕卡德儿童医院的医院学校试行的，斯坦福大学的本科生和研究生参与了这项计划的开发。正在进行的努力旨在将这一计划作为医院-学校教育的普通实验室科学课程在全国范围内广泛传播。为了实现这一目标，该项目将开发视频和在线教学辅助工具，进一步促进实验室的实施。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。

NONTECHNICAL SUMMARYThis research project is aimed to develop theoretical and computational approaches to modeling soft polymeric materials across scales of length from the individual molecules to the scales of bulk materials. Polymeric materials are ubiquitous in our daily lives, and they play a significant role in virtually every technological area. The current predictive framework for the behavior of soft polymeric materials can be divided into two different philosophical approaches. The first is based on detailed models down to the level of atoms; these are frequently computationally intractable for exhaustive discovery of polymeric materials. The second, more computationally tractable approach, is based on low resolution representations of polymers from which general predictions of physical behavior can be made, but at the expense of molecular-level detail. This research project is aimed to build a roadmap for bridging between these disparate perspectives that leverages the strength of each approach while avoiding their individual shortcomings. The goal is to enable the study of a wide range of properties of polymeric materials that were previously impossible to capture. This research project also provides a platform for training theorists and computational scientists who will be able to tackle a diverse range of fundamental and applied problems in soft materials. The research and educational goals of this project are complemented by broader outreach through the development of a dynamic program called LABScI. Laboratory Activities for Broadened Scientific Instruction. This program develops and implements laboratory science and engineering teaching modules for the education of high school students that are being treated for childhood cancer and other illnesses. This program is piloted at the Hospital School at the Lucile Packard Children's Hospital with engagement from undergraduate and graduate students at Stanford to develop the program. Ongoing efforts aim to broadly disseminate this program nationally as a general laboratory science curriculum for hospital-school education. Towards this goal, this project will develop videos and online teaching aids that further enable the implementation of the labs. TECHNICAL SUMMARYThis research project is aimed to develop theoretical and computational approaches to modeling soft polymeric materials across scales of length from the individual molecules to the scales of bulk materials. Current understanding of polymeric materials is largely based on coarse-grained models, but the development of high-performance computational simulations offers new levels of granular detail that would be invaluable for materials development. Bridging these scales is a hallmark problem in soft-materials physics. The PI aims to systematically incorporate varying levels of detail to capture the multi-scale behavior in polymeric materials. The foundational work in this research program will offer new and critical insight into the mesoscopic behavior of polymeric materials, which is a crucial length scale for many material phenomena for technological applications. This project aims to tackle key problems in soft materials self-assembly and thermodynamic behavior that require bridging these disparate perspectives through identifying an intermediate-scale physical model that is amenable to theoretical analysis while containing sufficient granular detail to compare with a detailed model. Semiflexible polymers are defined to have a level of detail that bridge these two perspectives, and fundamental work in describing the statistical behavior of such materials acts as critical input in this theoretical effort. This research program addresses the physical behavior of semiflexible polymer solutions and materials by (1) building a software package to predict the thermodynamic behavior of semiflexible polymers, (2) predicting the impact of semiflexibility and fluctuations in copolymer materials exhibiting structural and liquid-crystalline order, and (3) determining the impact of polymer and solvent ordering in the phase behavior of polyelectrolyte materials. These key areas of exploration provide deliverable tools and results that interface directly with existing theoretical, computational, and experimental approaches in soft materials. This effort may also shed new light on how granular molecular interactions influence the mesoscopic behavior in soft polymeric materials.This research project also provides a platform for training theorists and computational scientists who will be able to tackle a diverse range of fundamental and applied problems in soft materials. The research and educational goals of this project are complemented by broader outreach through the development of a dynamic program called LABScI. Laboratory Activities for Broadened Scientific Instruction. This program develops and implements laboratory science and engineering teaching modules for the education of high school students that are being treated for childhood cancer and other illnesses. This program is piloted at the Hospital School at the Lucile Packard Children's Hospital with engagement from undergraduate and graduate students at Stanford to develop the program. Ongoing efforts aim to broadly disseminate this program nationally as a general laboratory science curriculum for hospital-school education. Towards this goal, this project will develop videos and online teaching aids that further enable the implementation of the labs.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.