Non-Colligative Anti-Freeze Macromolecular Materials

PART 1: NON-TECHNICAL SUMMARY This award will support the study of new concepts and materials to control the freezing of water which would lead to broadly positive societal and technological benefits in biotechnology. Conventional anti-freezes like road salt inhibit ice formation by reducing the melting point of water. This feature is related to the large number of molecules that are being used called colligative suppression of freezing. In this project, the PI will investigate structure-property relationships of non-colligative anti-freezes where only a small amount of material can have an outsized effect on the freezing of water relative to conventional anti-freezes such as road salt or glycol. The results will lead to knowledge that will enable the creation of more effective non-colligative anti-freezes where only a small quantity of material would be required to, for example, freeze cells or living tissue without damaging them on thawing - a feature of potential lifesaving importance. The research could also lead to replacement of the seasonal application road salt or improve biobanking of agricultural resources that strengthens our food supply chain. In addition to advancing technology of anti-freeze, this research is having a broader impact by providing education and research training to interested undergraduate and graduate students. Additional outreach efforts are focused on interaction with K-12 students through on-campus introduction to non-colligative anti-freeze at Explore UT at the University of Texas-Austin hosting all interested students and their families. PART 2: TECHNICAL SUMMARY The research is focused on changing the inherent interactions of polymers and water and/or ice by changing the molecular structure of the poly(vinyl alcohol) (PVA), one of the only polymers that controls the freezing of water. First, the research examines how PVA behaves near the surface of ice crystals. Unlike small molecules that drift away, these polymers tend to stay near the ice because they form many hydrogen bonds with water and the ice itself. By staying in place, they can slow down ice growth by blocking water transport and preventing crystals from merging. The researchers will also test modified versions of PVA to see how changes in bonding strength affect ice formation, helping uncover general rules for designing antifreeze materials. Next, the research will focus on understanding why these polymers work. The team will measure how strongly the polymers interact with water using a fluorescence-based method. Hypotheses involving hydrogen bonding, surface activity, and changing surface tension and their influence on ice formation will be tested. Finally, the researchers will explore combining different antifreeze polymers. By linking PVA variants with another polymer that reduces total ice formation, the team aims to create a more powerful antifreeze material that combines multiple non-colligative anti-freeze effects. 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: 2604138 | Program: 01002627DB NSF RESEARCH & RELATED ACTIVIT | Principal Investigator: Nathaniel Lynd | Institution: University of Texas at Austin, AUSTIN, TX | Award Amount: $420,424 View on NSF Award Search: https://www.nsf.gov/awardsearch/show-award/?AWD_ID=2604138 View on Research.gov: https://www.research.gov/awardapi-service/v1/awards/2604138.html