RII Track-4: Advanced Morphology Characterization of Nanostructured Cyclic and Linear Polymers and their Blends

Tulane University, New Orleans LA

Investigators

Abstract

Non-Technical Description Over the past thirty years, tremendous advancements have occurred in the microelectronics and healthcare industries, resulting in phones that are more powerful than the earliest computers and medical treatments that are more effective, less invasive, and capable of treating formerly untreatable ailments. This rapid technological growth was enabled by the creation of new materials and efforts to fully understand their chemical and physical properties. In order to sustain this level of growth, the search for new materials must continue. This project supports collaboration between university researchers and scientists from government laboratories in this search. In one area, fundamental research into the properties of block copolymers, a type of nanostructured rubbery plastic material, promises a new route to lithographic patterning on the nano-scale to facilitate the move from micro-electronics to nano-electronics that are faster and capable of greater data storage. In a second area, studies on biocompatible, biodegradable, semi-crystalline polymers will reduce the need for undesirable small molecule additives to control crystallization, thereby enhancing biocompatibility and safety for use in medical applications. The project promotes scientific advancement by supporting experiments that can be conducted only in state-of-the-art national laboratories. By nurturing close interactions between academia and government, the project trains students to connect their educational experiences to the goals of national health, prosperity, welfare, and the production of civically-mindful scientists and engineers. Technical Description The cyclic molecular architecture endows polymer materials with unique and useful physical properties compared to linear counterparts such as smaller nanostructure domain sizes in block copolymers and greater thin film stability. These polymers show great promise as additives for endowing linear polymer systems with desirable properties. However, the molecular level integration of linear and cyclic materials in topological blends is not well-understood. Advanced characterization experiments made possible through this fellowship produce the fundamental knowledge necessary to understand how topological blends (linear plus cyclic polymers) can be used to (1) enhance block copolymer nanostructure properties for nanolithgraphy and (2) regulate crystallization kinetics and morphology in semi-crystalline polymer films. These goals are achieved by revealing molecular mechanisms in these systems using resonant soft X-ray reflectivity (RSoXR) for the characterization of molecular distributions in block copolymer systems and broadband coherent anti-Stokes Raman scattering (CARS) for mapping the localization components in semi-crystalline polymer blend films. Host site visits, in which the PI and students work closely with experts at the National Institute of Standards and Technology, are important for understanding organization of materials at the molecular level and for sustaining long-term academic-government collaboration. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.