Theory of hierarchically structured soft matter

层次结构软物质理论

• 批准号: RGPIN-2017-05351
• 负责人: Shi, AnChang
• 金额: $ 5.1万
• 依托单位: McMaster University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2019
• 资助国家: 加拿大
• 起止时间: 2019-01-01 至 2020-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=691578
• 关键词: Theory; hierarchically; structured; soft; matter

This proposed research program focuses on the development of new concepts, theoretical frameworks, and methodologies for the study of hierarchically structured soft matter self-assembled from macromolecular systems. The study will be carried out using block copolymers as a primary model system. Block copolymers are macromolecules composed of two or more chemically distinct sub-chains or blocks. The competition between the repulsion between the different blocks and the chain connectivity drives these macromolecules to form ordered structures or morphologies with nanometer-sized domains of different sizes and shapes. For example, recent experiment and theory have demonstrated that block copolymers can self-assemble into an extremely complex spherical packing phase (the so-called Frank-Casper -phase) with five types of domains of different shapes. The ability of block copolymers to form well-ordered nanostructures with domains of very different physical properties provides a powerful platform to engineer and control materials with desirable morphologies. These hierarchically nanostructured polymeric materials could have many useful applications, including periodically ordered soft materials for photonic crystals, nanosized vesicles for drug delivery, and sub-nanometer patterns for next-generation lithography. The objective of this proposed research program is to develop molecule-based theories to understand and predict the emergence, stability, and physical properties of hierarchically structured soft matter. ******The formation of hierarchically structured polymeric materials involves a number of components with diverse physical attributes such as chain topology, molecular size, rigidity, and chirality. Furthermore, the interactions between these monomers could be more complicated than the usual non-specific van der Waals interactions. Examples of these complicated interactions are hydrogen bonding and electrostatic interactions. To study systems with these diverse properties, I will develop theoretical frameworks for polymeric systems composed of complex architectures and rigid and/or chiral components. Specifically, my proposed research program includes three inter-related topics: (1) The structure and phase transition of multiblock copolymers, focusing on the emergence, mechanism of formation, and properties of hierarchically structured polymeric materials; (2) The phase behavior of polymeric systems containing semiflexible, chiral and associative components, focusing on the effects of molecular size, shape, rigidity and association on the self-assembled phases; (3) The structure and morphology of amphiphilic block copolymer solutions, focusing on the formation and property of nanosized aggregates including bilayer membranes.

该研究计划的重点是发展新的概念，理论框架和方法，用于研究从大分子系统自组装的分层结构软物质。将使用嵌段共聚物作为主要模型系统进行研究。嵌段共聚物是由两个或更多个化学上不同的子链或嵌段组成的大分子。不同嵌段之间的排斥和链连接之间的竞争驱动这些大分子形成具有不同尺寸和形状的纳米尺寸域的有序结构或形态。例如，最近的实验和理论已经证明，嵌段共聚物可以自组装成具有五种不同形状的域的极其复杂的球形填充相（所谓的Frank-Casper相）。嵌段共聚物形成具有非常不同的物理性质的域的良好有序的纳米结构的能力提供了一个强大的平台，以工程师和控制具有所需形态的材料。这些分级纳米结构的聚合物材料可以有许多有用的应用，包括用于光子晶体的周期性有序软材料，用于药物递送的纳米囊泡，以及用于下一代光刻的亚纳米图案。该研究计划的目标是发展基于分子的理论，以理解和预测分层结构软物质的出现，稳定性和物理特性。** 分层结构聚合物材料的形成涉及具有不同物理属性（例如链拓扑结构、分子大小、刚性和手性）的许多组分。此外，这些单体之间的相互作用可能比通常的非特异性货车范德华相互作用更复杂。这些复杂的相互作用的例子是氢键和静电相互作用。为了研究具有这些不同特性的系统，我将开发由复杂结构和刚性和/或手性组分组成的聚合物系统的理论框架。具体而言，我的研究计划包括三个相互关联的主题：（1）多嵌段共聚物的结构和相变，重点是分层结构聚合物材料的出现，形成机制和性能;（2）含半柔性、手性和缔合组分的聚合物体系的相行为，着重于分子大小、形状、（3）两亲性嵌段共聚物溶液的结构和形态，重点研究了纳米聚集体（包括双层膜）的形成和性质。