CAREER: Colloids with programmable surfaces: A polymer approach to self-assembly

New York University, New York NY

Investigators

Abstract

Non-Technical Description There is a fascinating way of imparting new properties to a material that does not require altering its chemical composition, but rather changing the structural arrangement of matter within the material itself. Creating an underlying microstructure can enable bulk materials to interact with energy in unique and unconventional ways. The result are emerging new properties that do not normally exist in nature. The practical realization of such materials, however, is not straightforward, as it requires creating microscopic features that are regularly spaced throughout a three-dimensional object. While this is not achievable via a classic top-down approach, colloidal self-assembly offers a conceptually simple route to impart such microscopic order in a bottom-up fashion. The principal investigator seeks to discover novel methodologies to manipulate and rationally assemble microscopic building blocks into complex micro-architectures and ultimately into functional new materials. Inexpensive polymers and simple electrostatic charges are used to mediate the binding interactions between the building blocks, thus effectively imparting assembly information. The results are complex "soups" of colloidal building blocks from which new materials are expected to self-assemble and emerge. The inherent interdisciplinary character of the project, which naturally bridges between chemistry, physics, and material science, offers a broad range of teaching opportunities from high school to graduate students. Educational and broader outreach goals include the development of a publicly available "colloidal library" - a Web Portal that connects students with research experts from various fields of science and industry. Technical Description While the whole field of colloidal self-assembly is rapidly converging towards the use of DNA to mediate particle interactions and impart precise assembly instructions, this research addresses a new and intriguing DNA-free approach to programmable self-assembly. The research team investigates polymer-mediated colloidal interactions and proposes them as new general tools for manipulating and assembling colloidal matter. Building on the principal investigator's expertise in synthetic colloidal chemistry and soft-matter physics, the project aims to: (i) develop a modular synthetic platform for the rapid prototyping of polymer-coated colloids, (ii) use the resulting colloidal model systems to study a broad range of polymer-mediated colloidal interactions (both enthalpy and entropy driven), and (iii) use this knowledge to develop inexpensive and scalable methodologies to program the self-assembly behavior of complex colloidal fluids. This project lays the foundation for the next generation of programmable self-assembling colloidal materials.