Crystalline Conjugated Block Copolymer Self-Assembly

优化有机光电器件、生物膜和药物传递应用的关键是理解控制纳米级自组装的热力学，这是特殊设计的聚合物材料。这是一个综合研究项目，旨在了解嵌段共聚物的自组装热力学，其中分子刚性和半结晶度影响聚合物的纳米结构和电荷传输特性。这个项目的一个重要组成部分包括若干综合教育活动。本科生和研究生将接受材料科学前沿领域的培训，参加地方和国家会议，并在进行这项研究的过程中与合作者密切互动。棒状线圈嵌段共聚物在最近优化有机光电器件的许多努力中发挥着核心作用，但很明显，结构必须在多个长度尺度上进行控制，从晶格中的原子间距到嵌段共聚物自组装的10纳米长度尺度以及器件的100纳米到微米尺度。这些努力的关键是理解这些相互作用是如何发生在截然不同的长度尺度上的。该项目的目标包括共轭嵌段共聚物的合成和自组装，对这些棒圈嵌段共聚物的相分离有基本的了解，并了解结构效应对电荷迁移率的相互作用。从长远来看，这种基本的理解将用于指导半柔性嵌段共聚物的设计，并最终影响有机光电子学和生物材料等领域。主链形状、嵌段共聚物自组装、结晶度和半导体性能之间的相互作用对于基本理解结构-性能关系以及未来设计具有可控性能的优化材料至关重要。在这里，将利用共轭棒圈嵌段共聚物的合成设计和自组装：(a)详细了解共轭聚合物（特别是聚噻吩衍生物）的链形、结晶度和电荷迁移率之间的关系；(b)了解在共轭棒圈嵌段共聚物中实现受限结晶的相关规则，以及这些纳米域内晶体的详细形态；(c)探索半柔性棒的作用，以及液晶和嵌段共聚物相互作用在共轭嵌段共聚物自组装中的平衡。

NON-TECHNICAL SUMMARYCritical to efforts for optimizing organic optoelectronic devices, biological membranes, and drug delivery applications is an understanding of the thermodynamics that control nanometer-scale self-assembly in specially designed polymeric materials. This is an integrated research program aimed at understanding the thermodynamics of self-assembly of block copolymers where molecular rigidity and semi-crystallinity affect the polymer nanostructure and charge transport properties. An important component of this project involves several integrated educational activities. Undergraduate and graduate students will be trained in forefront areas of materials science, participate in local and national meetings, and interact closely with collaborators in the process of performing this research. TECHNICAL SUMMARYRod-coil block copolymers play a central role in many recent efforts to optimize organic optoelectronic devices, but it is clear that structure must be controlled on multiple length scales ranging from the atomic spacing in a crystalline lattice to the 10 nm length scale of block copolymer self-assembly and the 100 nm to micron scale of the device. Critical to these efforts is an understanding of how these interactions occurring over drastically different length scales work in combination. The goals of this project involve the synthesis and self assembly of conjugated block copolymers, gaining a fundamental understanding of phase separation in these rod-coil block copolymers, and understanding the interplay of structural effects on charge mobility. In the longer term, this fundamental understanding will be used to guide the design of semiflexible block copolymers and ultimately impact fields such as organic optoelectronics and biomaterials.The interplay between backbone shape, block copolymer self-assembly, crystallinity, and semiconducting properties is crucial both for a fundamental understanding of structure-property relationships as well as for the future design of optimized materials with controllable properties. Here, synthetic design and self-assembly of conjugated rod-coil block copolymers will be utilized to: (a) Develop a detailed understanding of the relationship between chain shape, crystallinity, and charge mobility in conjugated polymers (particularly polythiophene derivatives); (b) Understand the rules associated with achieving confined crystallization in conjugated rod-coil block copolymers and the detailed morphology of crystals within these nanodomains, and (c) Probe the roles of semi-flexible rods and the balance between liquid-crystalline and block-copolymer interactions on conjugated block copolymer self-assembly.