CAREER: Composite Materials of Functional Block-copolymers and Nanoparticles: Understanding the Assembly Processes and Structure-property Relationships

技术综述：两亲性嵌段共聚物和纳米粒子的自组装为创建多功能纳米结构提供了一条有效的途径。然而，这两个组分的组装行为还没有被大力研究，研究人员一直依赖于简单的增溶方法将纳米颗粒包裹在聚合物基质中。Park小组最近表明，纳米颗粒和嵌段共聚物的合作组装可以在离散的嵌段共聚聚合物聚集体中产生有序的纳米颗粒阵列。这项拟议的研究将进一步探讨是什么控制了这两个组分在选择性溶剂中的共同组装过程，以及纳米粒子如何影响嵌段共聚物的形态和性能。这些知识是设计具有预先设想的结构和性能的纳米颗粒/聚合物复合材料的关键。此外，Park小组将把这一策略扩展到包含共轭聚合物链段的嵌段共聚物，其中嵌段共聚物不仅充当结构导向分子，而且还为复合系统提供额外的功能。这种独特的材料组合和嵌段共聚物的自组装能力将导致先进的多功能纳米到微米级材料，具有可控的结构和性能。非技术摘要：在聚合物中加入纳米粒子提供了一种有效的方法来控制软材料的机械、光学和电学性能，应用范围从柔性的、低成本的太阳能电池到生物成像和医学。这项研究旨在阐明纳米粒子和嵌段共聚物之间的相互作用如何影响聚合物/纳米粒子复合粒子的形态。这项研究将为选择合适的嵌段共聚/纳米粒子对和组装条件以制备具有理想结构和性能的复合材料提供指导。拟议活动的更广泛影响是寻求利用高度可见的纳米科学，以更好地让大学预科和本科生参与科学。在化学跨学科领域培养研究生和博士后研究员是这项拟议研究的另一个重要成果。这项拟议的研究使用了几个不同领域的概念和工具，包括材料科学、表面化学和光谱学。学生将在看似不相关的领域之间的界面上发现机会，并学习如何解决这些边界上的问题。

TECHNICAL SUMMARY: The self-assembly of amphiphilic block-copolymers and nanoparticles offers a powerful route to create multifunctional nanostructures. However, the assembly behavior of the two components has not been vigorously studied, and researchers have been relying on the simple solubilization approach to encapsulate nanoparticles in polymer matrixes. The Park group has recently shown that the cooperative assembly of nanoparticles and block-copolymers can lead to ordered arrays of nanoparticles in discrete block-copolymer aggregates. The proposed research will further investigate what controls the co-assembly process of the two components in selective solvents and how nanoparticles affect the morphology and properties of block-copolymers. Such knowledge is key to the design of nanoparticle/polymer composite materials with preconceived architecture and properties. Furthermore, the Park group will extend the strategy to block-copolymers containing conjugated polymer segments, where block-copolymers not only act as structure-directing molecules but also provide an additional functionality to the composite system. This unique combination of materials and the self-assembly capability of block-copolymers will lead to advanced multifunctional nanometer to micrometer scale materials with controllable structure and properties.NON-TECHNICAL SUMMARY:The incorporation of nanoparticles in polymers offers an effective way to control the mechanical, optical, and electrical properties of soft materials for applications ranging from flexible, low-cost solar cells to biological imaging and medicine. The proposed research aims to elucidate how the interactions between nanoparticles and block-copolymers affect the morphology of polymer/nanoparticle composite particles. This study will provide a guide for selecting suitable block-copolymer/nanoparticle pairs and assembly conditions to create composite materials with desirable architectures and properties. The broader impact of the proposed activity seeks to exploit highly visible nanoscience to better engage pre-college and undergraduate students in science. Educating graduate students and postdoctoral fellows in an interdisciplinary field of chemistry is another important outcome of the proposed study. The proposed research uses concepts and tools in several different areas including materials science, surface chemistry, and spectroscopy. Students will discover opportunities at the interfaces between seemingly unrelated fields and learn how to solve problems at those boundaries.