NSF-DFG Confine: MolPEC – Molecular Theory of Weak Polyelectrolytes in Confined Space

NSF-DFG Confine：MolPEC — 密闭空间弱聚电解质的分子理论

基本信息

批准号：
2234013
负责人：
Jianzhong Wu
金额：
$ 40万
依托单位：
University of California-Riverside
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2022
资助国家：
美国
起止时间：
2022-11-01 至 2025-10-31
项目状态：
未结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=2234013&HistoricalAwards=false
关键词：
NSF DFG Confine MolPEC Molecular

项目摘要

In this project supported by the Chemical Theory, Models and Computational Methods Program (CTMC) of the Division of Chemistry, Professor Jianzhong Wu of the University of California-Riverside is developing theoretical models that describe a class of polymers known as weak polyelectrolytes (WPEs). This is a collaborative project with researchers from the Georg-August-Universität Göttingen, Germany. WPEs are a large class of macromolecules that may either protonate or deprotonate depending upon the environmental conditions such as pH and salt concentration. Their stimuli-responsive behavior has been broadly utilized in functional “smart” materials for applications such as targeted drug delivery or underwater adhesion. Whereas practical applications often entail chemical and physical processes under spatial confinement, the structure and dynamics of WPEs remain incompletely understood due to the strong coupling of reaction and polymer-mediated correlations at both monomer and polymer scales. The rational design of WPE systems is calling for advances in theoretical and computational methods that are able to accurately describe confinement effects on local solution environment, protonation/deprotonation equilibrium, and the dynamics of polymers reacting with ionizable surfaces. This research aims to develop a theoretical framework for describing the properties of WPEs in confined space and their responses to environmental conditions including solution pH, electrolyte composition, and the chemistry of confinement. We will utilize these techniques to investigate the interplay between ionic size, valence, ionization, surface reactions and the dynamics of polymer binding that cannot be reliably addressed with conventional methods. The theoretical and computational advances will contribute to a rational design of weak polyelectrolyte systems for a wide spectrum of technological applications. Building on complementary advances in polymer density functional theory (PDFT) and molecular simulation, the US-German team will study the structure, thermodynamics, and dynamics of weak polyelectrolytes at and between surfaces. The idea is to combine and extend Ising Density Functional Theory (iDFT) and Single-Chain-in-Mean-Field (SCMF) simulation. iDFT considers single-chain configurations and ionization states of segments on equal footing and captures liquid-like packing and electrostatic correlations via the molecular density. The joint probability distribution of configurations and ionization states of an entire macromolecule is dictated by a single-chain potential, which, in turn, is a functional of the molecular density. The high-dimensional molecular density will be efficiently evaluated via SCMF simulation on parallel, GPU-accelerated supercomputers, employing the iDFT single-chain potential. The team will extend the simulation code, SOft coarse-grained Monte-carlo Acceleration (SOMA), to incorporate electrostatic interactions and nonlocal interactions along the molecular contour. The particle-based simulation, Dynamic-iDFT (D-iDFT), accounts for long-range fluctuations and allows us to study the configuration dynamics. Additionally, we will derive a segment-based dynamic iDFT (SD-iDFT) for describing the local polymer mass and charge density in response to environmental changes. The generic nature of the theoretical techniques proposed in this work ensures broad applications to diverse phenomena in polymeric and biological systems. This project will provide training opportunities for early career scientists to gain interdisciplinary research experience and cultivate their career interests in computational molecular engineering. In addition to supporting graduate students, it offers research-based thesis projects for undergrads in active military service, veterans, and students from the University Honors Program (UHP). This project is being awarded through the “Chemistry and Transport in Confined Spaces (NSF-DFG Confine)" opportunity, a collaborative solicitation that involves the National Science Foundation and Deutsche Forschungsgemeinschaft (DFG).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.

在化学理论，化学理论支持化学理论的支持下，化学划分的模型和计算方法计划（CTMC），加利福尼亚 - 里弗赛大学的江港教授正在开发理论模型，这些模型描述了一类称为弱聚电解质的聚合物（WPES）。这是一个合作项目，与来自德国乔治 - 奥格斯特·戈丁根的研究人员。 WPE是一大类的大分子，可以根据pH和盐浓度等环境条件，可能质子培或去质子酸盐。它们的刺激性反应性行为已广泛用于功能性的“智能”材料中，以用于靶向药物或水下依从性。尽管实际应用通常需要在空间限制下进行化学和物理过程，但由于单体和聚合物尺度的反应和聚合物介导的相关性的强烈耦合，WPE的结构和动力学仍未完全理解。 WPE系统的合理设计呼吁在理论和计算方法中取得进步，这些方法能够准确地描述对局部溶液环境，质子化/去质子化等效效果以及聚合物的动力学对电离表面反应的动力学。这项研究旨在开发一个理论框架，以描述限制空间中WPE的特性及其对环境条件的反应，包括溶液pH，电解质组成和限制化学。我们将利用这些技术来研究离子大小，价，电离，表面反应与聚合物结合的动力学之间的相互作用，这些动态无法用常规方法可靠地解决。理论和计算进步将有助于多种技术应用的弱聚电解质系统的合理设计。美国 - 德国团队的基础是聚合物密度功能理论（PDFT）和分子模拟的基础上，将研究表面和表面之间弱聚电解质的结构，热力学和动力学。这个想法是结合和扩展Ising密度功能理论（IDFT）和单链磁场（SCMF）模拟。 IDFT考虑了相等地位的片段的单链构型和电离状态，并通过分子密度捕获液状填料和静电相关性。整个大分子的构型和电离状态的关节概率分布取决于单链电位，这反过来又是分子密度的功能。高维分子密度将通过使用IDFT单链电位在平行的，GPU加速的超级计算机上通过SCMF模拟进行有效评估。该团队将扩展模拟代码，即软颗粒的蒙特卡洛加速度（SOMA），以结合沿分子轮廓的静电相互作用和非局部相互作用。基于粒子的仿真动态idft（d-idft）是远程波动的解释，并使我们能够研究配置动力学。此外，我们将得出一个基于段的动态IDFT（SD-IDFT），用于描述局部聚合物质量和电荷密度，以响应环境变化。这项工作提出的理论技术的通用性质可确保对聚合物和生物系统中潜水现象的广泛应用。该项目将为早期的职业科学家提供培训机会，以获得跨学科研究经验，并培养其在计算分子工程方面的职业兴趣。除了支持研究生外，它还为现役兵役，退伍军人和大学荣誉计划（UHP）的本科生提供基于研究的论文项目。该项目是通过“封闭空间（NSF-DFG限制）的化学和运输”机会授予的，这是一种协作招标，其中涉及国家科学基金会和德意志福斯施加斯格梅夏夫特（DFG）。该奖项反映了NSF的法定任务，并通过评估了CRETIRETIRATIL IDECTIAL IXPERTIAL IFFICTIAL MERITIAL MERITIAL和FORGIALIAL和FRADICAIL和FRODIARIAL和FRODIARIARIAL和FRODIRIAL和FRODIARIARIAL和FRODIARIARIARIARIATIAL。