Field-Theoretic Polymer Simulations: Fundamentals and Applications

场论聚合物模拟：基础知识和应用

• 批准号: 0603710
• 负责人: Glenn Fredrickson
• 金额: $ 30万
• 依托单位: University of California-Santa Barbara
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-08-15 至 2009-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0603710&HistoricalAwards=false
• 关键词: Field; Theoretic; Polymer; Simulations; Fundamentals

TECHNICAL SUMMARY:This award supports computational and theoretical research and education in the area of polymer simulation. This project will build on the recent development by the PI and co-workers of the "field-theoretic simulation" (FTS) method, enabling numerical investigations of field theory models of polymers, complex fluids, and soft materials without resorting to the mean-field approximation. The proposed research encompasses both fundamental and applied components.. Foundations and extensions of the FTS method. This research thrust will include development of improved numerical schemes for time integration of the stochastic "complex Langevin" equations used to implement potential field updates. We also propose to develop a new "ground state-FTS" technique that should dramatically accelerate simulations of strongly overlapping polymer solutions (neutral and charged) in the semi-dilute and concentrated regimes.. Numerical renormalization group theory. We propose to implement pseudospectral numerical RG transformations in tandem with complex Langevin simulations of polymer field theories. This will facilitate the isolation of lattice cutoff effects and enable systematic coarse-graining of polymer solution models. The PI envisions applications to block copolymers in selective solvents.. Hybrid particle-field simulations. We propose to develop a new class of simulations for treating nanoparticles or colloids embedded in structured polymer fluids. The particles are treated as "cavities" in the fluid fields and the particle coordinates are retained along with the fluid field variables.. Defects in confined copolymer films. Translational and bond-orientational order will be examined in FTS simulations of block copolymer films with perimeter boundary conditions. The results will be used to assess the efficacy of grapho-epitaxy for creating defect-free copolymer films that can be used in ultra-high density patterning of advanced electronic, optical, and magnetic devices. The proposed research will closely couple with an experimental program underway in the laboratory of Edward J. Kramer at UCSB.The PI will continue in his tradition of effective graduate and post-doctoral training in theoretical and computational polymer science. A particular focus will be to expose students and post-docs with classical physics training to broader soft materials/polymer science disciplines through a close coupling with experimental groups at UCSB in chemical engineering, materials, and chemistry. The fundamental understanding gained under the proposed project will be further leveraged through the Complex Fluids Design Consortium (CFDC) at UCSB, an industry-national lab-academic partnership that is addressing the computational design of commercial polymer and complex fluid formulations.NON-TECHNICAL SUMMARY:This award supports computational and theoretical research and education in the area of polymer science using computers to simulate polymer materials and polymer-related phenomena. The PI plans to continue his work on fundamental theoretical advances and new algorithms aimed at extending a simulation method he developed and at developing new simulation methods for inhomogeneous polymer materials, complex fluids, and soft materials. These methods are needed to handle essential physics that arises across diverse length and time scales in these materials and often makes reliable computer simulation difficult. In an effort coupled to experiment, the PI plans to apply these newly developed advanced simulation methods to thin films of block copolymers and to investigate a promising experimental technique for creating nearly perfect copolymer films that can be used as a template to synthesize inorganic nanowires, nanodots, and other nanoscale structures. The PI will continue in his tradition of effective graduate and post-doctoral training in theoretical and computational polymer science. A particular focus will be to expose students and post-docs with classical physics training to broader soft materials/polymer science disciplines through a close coupling with experimental groups at UCSB in chemical engineering, materials, and chemistry. The fundamental understanding gained under the proposed project will be further leveraged through the Complex Fluids Design Consortium (CFDC) at UCSB, an industry-national lab-academic partnership that is addressing the computational design of commercial polymer and complex fluid formulations.

技术概述：该奖项支持聚合物模拟领域的计算和理论研究和教育。该项目将建立在PI及其同事最近发展的“场论模拟”（FTS）方法的基础上，使聚合物，复杂流体和软材料的场论模型的数值研究无需诉诸平均场近似。拟议的研究包括基础和应用两个部分。FTS方法的基础和扩展。这项研究的重点将包括发展用于实现势场更新的随机“复朗之万”方程的时间积分的改进数值格式。我们还建议开发一种新的“基态- fts”技术，该技术将大大加速半稀释和浓缩状态下强重叠聚合物溶液（中性和带电）的模拟。数值重整化群论。我们建议将伪光谱数值RG变换与聚合物场理论的复杂朗之万模拟结合起来实现。这将有助于隔离晶格切断效应，并使聚合物溶液模型的系统粗粒化成为可能。PI设想在选择性溶剂中嵌段共聚物的应用。混合粒子场模拟。我们建议开发一类新的模拟来处理嵌入在结构聚合物流体中的纳米颗粒或胶体。粒子被视为流体场中的“空腔”，粒子坐标与流体场变量一起被保留。局限共聚物薄膜缺陷。平移和键取向顺序将在具有周界条件的嵌段共聚物薄膜的FTS模拟中进行检查。该结果将用于评估石墨外延在制造无缺陷共聚物薄膜方面的功效，该共聚物薄膜可用于先进电子、光学和磁性器件的超高密度图案。拟议的研究将与UCSB的爱德华·j·克莱默实验室正在进行的一个实验项目密切相关。PI将继续他在理论和计算聚合物科学方面有效的研究生和博士后培训的传统。通过与加州大学圣迭戈分校化学工程、材料和化学实验组的密切合作，将重点放在让接受过经典物理训练的学生和博士后接触更广泛的软材料/聚合物科学学科。UCSB的复杂流体设计联盟（CFDC）是一个工业-国家实验室-学术合作伙伴关系，致力于商业聚合物和复杂流体配方的计算设计，在该项目中获得的基本知识将进一步得到利用。非技术总结：该奖项支持使用计算机模拟聚合物材料和聚合物相关现象的聚合物科学领域的计算和理论研究和教育。PI计划继续他在基础理论进步和新算法方面的工作，旨在扩展他开发的模拟方法，并开发非均质聚合物材料，复杂流体和软材料的新模拟方法。这些方法需要处理这些材料中出现的跨越不同长度和时间尺度的基本物理，并且通常使可靠的计算机模拟变得困难。在与实验相结合的努力中，PI计划将这些新开发的先进模拟方法应用于嵌段共聚物薄膜，并研究一种有前途的实验技术，以创造近乎完美的共聚物薄膜，这种共聚物薄膜可以用作合成无机纳米线、纳米点和其他纳米级结构的模板。PI将继续他在理论和计算聚合物科学方面有效的研究生和博士后培训的传统。通过与加州大学圣迭戈分校化学工程、材料和化学实验组的密切合作，将重点放在让接受过经典物理训练的学生和博士后接触更广泛的软材料/聚合物科学学科。UCSB的复杂流体设计联盟（CFDC）是一个工业-国家实验室-学术合作伙伴关系，致力于商业聚合物和复杂流体配方的计算设计，在该项目中获得的基本知识将进一步得到利用。