Studies of self-assembly in soft materials

拟议的研究涉及软材料的研究，包括聚合物、液晶、表面活性剂溶液、胶体悬浮液和生物材料，如脂质膜和生物分子组件。将基本物理思想应用于软物质研究是现代物理学的主要发展领域之一。我的研究项目主要集中在软材料的自组装。这些项目旨在阐明具有可控内部结构的软质材料的设计和优化的基本原理和指导，并为理解一般物理系统（如表面活性剂、脂质和病毒）的自组装提供有用的范例。具体来说，选择嵌段共聚物作为模型体系进行研究。这一选择是基于嵌段共聚物在技术上的重要性，其相行为的丰富性，以及我在理论聚合物物理方面的专业知识。嵌段共聚物是由化学上不同的嵌段系在一起组成的大分子，它们自发地形成各种有序相，畴尺寸在纳米范围内（1-100nm）。在过去的几十年里，了解嵌段共聚物的结构和相变一直是高分子科学中最活跃的研究领域之一。目前的提案延续了我过去在这一领域的成功，重点关注具有复杂分子结构的嵌段共聚物的自组装和热力学性质。我们将研究一些相互关联的项目。(1)多嵌段共聚物的结构和相变研究，重点关注复杂有序结构的发生。(2)研究了含半柔性和/或手性嵌段共聚物的相行为，重点研究了链结构对自组装相的影响。(3)考察外加电场或约束场等外场的影响，重点研究外力如何有目的地操纵自组装过程。

The proposed research concerns with the study of soft materials including polymers, liquid crystals, surfactant solutions, colloidal suspensions, and biological materials such as lipid membranes and biomolecular assemblies. The application of basic physics ideas to the study of soft matter is one of the major growth areas of modern physics. My research projects focus on self-assembly of soft materials. These projects are designed to elucidate fundamental principles and guidance for the design and optimization of soft materials with controlled internal structures, as well as providing a useful paradigm for understanding self-assembly of general physical systems such as surfactants, lipids and virus.Specifically, block copolymers are chosen as a model system for the study. This choice is based on the importance of block copolymers in technology, the richness of their phase behavior, and my expertise in theoretical polymer physics. Block copolymers are macromolecules composed of chemically different blocks tethered together, which spontaneously form a variety of ordered phases with domain sizes in the nanoscopic range (1-100nm). Understanding the structure and phase transitions observed in block copolymers has been the one of the most active research areas in polymer science in the past decades. The current proposal continues my past success in this area, focusing on the self-assembly and thermodynamic properties of block copolymers with complex molecular structures. We will study a few inter-related projects. (1) The studies of the structure and phase transition of multi-block copolymers, focusing on the occurrence of complex ordered structures. (2) The investigation of the phase behavior of block copolymers containing semi-flexible and/or chiral blocks, focusing on the effects of chain structure on the self-assembled phases. (3) The examination of the effects of external fields such as applied electric field or confinement field, focusing on how self-assembly processes can be purposefully manipulated by external forces.