多级手性纳米材料中手性传递的力学研究

Many nanomaterials such as twisted chiral polymer lamellae have hierarchy of chirality, can usually induce super mechanical, optical and electric properties. Thus, nanomaterials with hierarchy of chirality hold promise for a wide diversity of important applications in micro/nano-electromechanical systems, optoelectronic devices and biological sensors as functional structural elements. The transfer of chirality among different structural levels determines to a large extent the morphologies and the mechanical properties of these nanomaterials. From the viewpoints of mechanics and physics, this project aims to gain insight into the physics mechanisms and the basic principles of the chirality transfer in nanomaterials with hierarchy of chirality by developing a theoretical framework and conducting computational simulations and experimental investigation. This project will firstly develop a hierarchical or multi-scale theoretical model and a corresponding simulation method for nanomaterials with hierarchy of chirality , and establish the relationship between the chemical chirality and surface or interface properties. Secondly,it will develop quantitative relationships among the chirality at different levels, and will reveal the physical mechanism behind this phenomenon and investigate its basic law . It will focus on how the chirality transfer affects the morphologies and the mechanical properties of nanomaterials, and will also investigate the size effects of the morphologies and the mechanical properties. This project not only indicates new way to control and optimize the morphologies and the mechanical properties of nanomaterials using chirality, but also provides new design principles which can be used to guide the developments of novel chirality-based functional nanomaterials and nanomaterials with hierarchial chiral structures.

手性高分子片晶等多级手性纳米材料由于在多结构层次上存在不同的手性，通常具有优异的力、光、电等多物理场性能，适合作为纳米机电系统、光电器件、生物传感器等的功能结构单元。手性在多结构层次的传递很大程度上决定着此类材料的形貌和性能。本项目拟针对多级手性纳米材料的手性传递问题，展开比较深入的理论分析、计算模拟和实验研究，以期从力学和物理的角度，增进对手性传递的物理机制和基本规律的认识。基于材料的多级手性和纳米尺度特征，发展适用于此类材料的多层次或多尺度的理论模型和计算模拟方法；建立化学手性和表面/界面性能之间的定量关系；研究不同结构层次上手性的定量联系，揭示手性传递的物理机制，探究手性的传递规律；对典型多级手性纳米材料，研究手性传递对材料形貌和性能的定量影响及其尺寸效应。本项目的研究不仅有助于利用手性调控材料形貌和性能，还为多级手性结构纳米材料和手性功能材料的设计提供力学原理。

手性高分子片晶等多级手性材料由于在多结构层次上存在不同的手性，通常具有优异的力、光、电等多物理场性能，适合作为纳米机电系统、光电器件、生物传感器等的功能结构单元。本项目针对多级手性传递和相关的力学问题，展开比较深入的理论分析、计算模拟和实验研究。结合用实验和理论建模，研究了攀附卷须中的多级手性传递；建立了多级手性传递的一般力学模型，揭示了其遵循的二个基本规律；建立了手性纳米线的梁模型，研究了其弯曲和屈曲；建立了用微螺旋调控宏观形貌的基本力学模型；模拟了螺旋纤维拔出的力学行为； 给出了手性翻转的的力学模型，研究了铁电纳米线螺旋中的宏微观极化场。上述关于手性材料的研究不仅有助于利用手性调控材料形貌和性能，还为多级手性结构纳米材料和手性功能材料的设计提供力学原理