Theoretical Studies of Inhomogeneous Polymers

非均相聚合物的理论研究

• 批准号: 0312097
• 负责人: Glenn Fredrickson
• 金额: $ 32.4万
• 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: 2003
• 资助国家: 美国
• 起止时间: 2003-07-15 至 2006-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0312097&HistoricalAwards=false
• 关键词: Theoretical; Studies; Inhomogeneous; Polymers

A comprehensive theoretical and computational investigation of the equilibrium properties on inhomogeneous polymers will be carried out. The research will build on the recent developments by the PI and co-workers on the field-theoretic computer simulation (FTS) method, enabling numerical investigations of field theory models of polymers and complex fluids without any simplifying assumptions such as the mean-field approximation. The research will have the following components: (1) Foundations of the FTS method: This will include development of improved algorithms for solving the complex diffusion equation central to the method and development of efficient numerical schemes for time integration of the complex Langevin equations used to implement chemical potential field updates. Real-space renormalization group theory will also be applied to isolate lattice cutoff effects and to enable systematic coarse-graining of polymer solution models. (2) Micelle phases in copolymer alloys: The FTS method will be applied to investigate micelle formation in block copolymers-homopolymer blends near mesophase unbinding transitions, where mean-field theory is expected to fail. (3) Block and graft copolymer systems with chemical disorder: Simplified models of poydisperse star-block and graft-block copolymers will be constructed in which both annealed and quenched disorder averages can be exactly carried out. The models will be numerically and analytically investigated to study the differences in self-assembly behavior between systems with the two types of disorder, the role of fluctuation effects, and the existence of compositional glass transitions. The overall objective is to gain a fundamental understanding of how chemical disorder, unavoidable in commercial copolymer materials, influences structure and thermodynamics. (4) Defect control in thin copolymer films: Translational and bond-orientational order will be examined in FTS simulations of block copolymer films with special perimeter boundary conditions. The results will be used to assess the efficacy of graphoepitaxy for creating defect-free copolymer films that can be used in ultra-high density patterning of advanced electronic, optical, and magnetic devices. The research will be closely coupled with experiments in the laboratory of E.J. Kramer at UCSB. The research will involve training of graduate students and post-doctoral researchers. The fundamental understanding gained through this project will be leveraged through a new Complex Fluids Design Consortium at UCSB, an industry-national lab-academic partnership that will address computational design of industrial polymer and complex fluid formulations.%%%A comprehensive theoretical and computational investigation of the equilibrium properties on inhomogeneous polymers will be carried out. The research will involve training of graduate students and post-doctoral researchers. The fundamental understanding gained through this project will be leveraged through a new Complex Fluids Design Consortium at UCSB, an industry-national lab-academic partnership that will address computational design of industrial polymer and complex fluid formulations.***

将对非均质聚合物的平衡特性进行全面的理论和计算研究。 该研究将建立在PI及其同事在场论计算机模拟（FTS）方法方面的最新进展的基础上，从而能够对聚合物和复杂流体的场论模型进行数值研究，而无需任何简化假设，例如平均场近似。 该研究将包含以下组成部分： (1) FTS 方法的基础：这将包括开发用于求解该方法核心的复杂扩散方程的改进算法，以及开发用于复杂 Langevin 方程时间积分的有效数值方案。实施化学势场更新。 实空间重正化群理论还将应用于隔离晶格截止效应并实现聚合物溶液模型的系统粗粒度化。 (2) 共聚物合金中的胶束相：FTS 方法将用于研究嵌段共聚物-均聚物共混物中接近中间相非结合转变的胶束形成，而平均场理论预计会在此处失效。 (3)具有化学无序性的嵌段和接枝共聚物体系：将构建多分散星形嵌段和接枝嵌段共聚物的简化模型，其中可以准确地进行退火和淬火的无序平均。 将对模型进行数值和分析研究，以研究具有两种无序类型的系统之间自组装行为的差异、波动效应的作用以及成分玻璃化转变的存在。 总体目标是从根本上了解商业共聚物材料中不可避免的化学无序如何影响结构和热力学。 (4) 共聚物薄膜中的缺陷控制：将在具有特殊周界边界条件的嵌段共聚物薄膜的 FTS 模拟中检查平移和键取向顺序。 结果将用于评估图形外延法创建无缺陷共聚物薄膜的功效，该薄膜可用于先进电子、光学和磁性设备的超高密度图案化。 该研究将与 E.J. 实验室的实验紧密结合。克莱默在加州大学圣巴巴拉分校。 该研究将涉及研究生和博士后研究人员的培训。 通过该项目获得的基本理解将通过 UCSB 的新复杂流体设计联盟得到利用，这是一个行业-国家实验室-学术合作伙伴关系，将解决工业聚合物和复杂流体配方的计算设计。%%%全面的理论和计算研究将进行非均质聚合物的平衡性质的研究。 该研究将涉及研究生和博士后研究人员的培训。 通过该项目获得的基本理解将通过加州大学圣巴巴拉分校新的复杂流体设计联盟得到利用，这是一个行业-国家实验室-学术合作伙伴关系，将解决工业聚合物和复杂流体配方的计算设计问题。***