SELECTIVE LIGHT-DRIVEN POLYMER CHEMISTRY USING BORON DIPYRROMETHENE PHOTOINITIATORS

University Of Texas At Austin, Austin TX

Investigators

Abstract

With the support of the Macromolecular, Supramolecular and Nanochemistry Program in the Division of Chemistry, Professor Zachariah A. Page of The University of Texas at Austin aims to develop innovative approaches to the synthesis of durable and/or recyclable plastics using a mild and renewable energy source, such as visible light. Dye molecules that absorb visible light will be synthesized and studied to understand their structure-reactivity relationships and to identify dye molecules that can activate distinct polymerization reactions based upon the conditions employed, such as the color or intensity of light exposure. In turn, a single precursor liquid comprising these dyes can be used to create multiple different plastics having a range of properties (e.g., optical, mechanical, thermal, etc.) by simply "toggling a light switch". Thus, the user picks the property desired (e.g., hard or soft material) for the application at hand and applies the corresponding stimulus. The fundamental chemistry knowledge to be gained has the potential to advance technologies of societal need in health and energy sectors, such as tissue engineering, microelectronics, adhesives, and optical coatings. This research will provide opportunities for undergraduate and graduate student training in polymer chemistry. Furthermore, the work will positively support public education and outreach. Professor Page will strive to break down mindset barriers to learning organic chemistry, empower students through peer mentorship, and engage middle and high school students with disproportionate populations of underrepresented groups in STEM fields to foster pursuit of higher education. Moreover, the dyes developed will be integrated into a research course for first year undergraduate students. This research will focus on the development of wavelength-selective boron dipyrromethene (BODIPY) photoinitiators to drive polymerizations with discrete mechanistic control. The structure of BODIPY-based dyes will be systematically modified for studying how their chemical and electronic properties influence selectivity and efficiency in initiating anionic step-growth polymerizations and radical chain-growth polymerizations. This research aims to establish the correlations of photoinitiation reactivity with the BODIPY structure as well as the wavelength and intensity of light. The fundamental chemistry knowledge to be gained will inform the rational design of photoinitiators and strategies for synthesizing recyclable polymers and polymer networks. Moreover, the inherent spatial control over the light-induced polymerization processes will enable advanced manufacturing, where the ability to control the polymerization mechanism by different light intensities and wavelengths will prove valuable for precision 2D patterning and 3D printing of polymers with defined composition, topology, and properties. 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.