Interfacial Mechanics of Water-Spread Polymer Micelles: Unraveling the Roles of Shape, Corona Architecture, and Core Dimensions

PART 1: NON-TECHNICAL SUMMARY Acute Respiratory Distress Syndrome is a life-threatening lung condition that affects hundreds of thousands of patients each year in the United States and millions worldwide. In this condition, the natural substance that keeps the lungs open becomes impaired, making it difficult for patients to breathe and for oxygen to enter the bloodstream. Existing treatments primarily provide supportive care and do not directly restore this essential function. In addition, current lipid-based surfactant therapies are often ineffective in severe cases because they are disrupted by proteins and enzymes in injured lungs. This project is expected to have significant impact in Biotechnology. This project seeks to develop a new type of synthetic material that can replace the failing lung surfactant and function reliably under these conditions. The research focuses on understanding how nanoscale polymer particles spread and behave at the air-water interface inside the lungs, which is critical for restoring normal breathing. By uncovering how particle structure controls behavior, the project aims to guide the design of improved materials for lung therapy. Beyond its potential to improve treatment for a serious and widespread condition, this work advances fundamental knowledge in materials science and interfacial phenomena. The project will support education and workforce development by training graduate and undergraduate students in interdisciplinary research spanning polymer science, engineering, and medicine. Outreach activities will engage K through 12 students and the broader community to promote interest in science and engineering. By integrating fundamental discovery with societal benefit, this project contributes to national priorities in health, innovation, and scientific leadership. PART 2: TECHNICAL SUMMARY This project will establish a fundamental framework for understanding how nanostructural characteristics of amphiphilic block copolymer micelles govern their interfacial mechanical behavior at the air-water interface. The research focuses on poly(styrene)-poly(ethylene glycol) micelles as a model system and investigates how micelle shape, corona chain architecture, and core dimensions influence surface pressure generation, compressibility, and structural stability relevant to lung surfactant function. Three integrated aims will be pursued. The first aim examines the role of micelle shape by comparing spherical and cylindrical micelles using Langmuir isotherms, X-ray reflectivity, grazing-incidence X-ray scattering, and Brewster angle microscopy to characterize interfacial structure and mechanical response. The second aim evaluates the influence of corona architecture by comparing linear and looped polymer brushes and by developing mixed brush micelles to probe structure-property relationships governing interfacial adsorption and stability. The third aim determines how molecular parameters such as block molecular weights, core size, and grafting density control micelle core rigidity through measurements of glass transition behavior using nuclear magnetic resonance, fluorescence methods, and temperature dependent interfacial analysis. Together, these studies will define structure-property relationships linking micelle design to interfacial mechanics, providing a predictive basis for engineering polymer-based surfactant systems for biomedical applications and biotechnology. 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. NSF Award ID: 2600112 | Program: 01002627DB NSF RESEARCH & RELATED ACTIVIT | Principal Investigator: You-Yeon Won | Institution: Purdue University, WEST LAFAYETTE, IN | Award Amount: $531,967 View on NSF Award Search: https://www.nsf.gov/awardsearch/show-award/?AWD_ID=2600112 View on Research.gov: https://www.research.gov/awardapi-service/v1/awards/2600112.html