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

University Of Pennsylvania, Philadelphia PA

Investigators

Abstract

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.