Polymers impact nearly every part of daily life - from the bristles on a toothbrush to the packaging that protects food. The chemical composition of a polymer dictates its properties including strength, flexibility, recyclability, etc., which define applications. In this research project, Prof. Pentzer at Case Western Reserve University and Prof. Lambrecht at University of Pittsburgh explore the use of ketenes, a class of under-utilized monomers, for preparing novel polymers with high mechanical strength, and yet high solubility for facile processing. Computational prediction is integrated with synthesis and characterization to enable cost- and time-efficient discovery of such new polymers. This multidisciplinary project provides research training to undergraduate and graduate students, preparing the future generation of skilled workforce in science and engineering fields.
The research team studies the chain growth polymerization of silyl ketenes, (R3Si(H)C=C=O), which form solution processable polymers with variable backbone and side groups that behave as rigid rod polymers (RRPs). Since silyl ketenes can yield three different polymer backbone chemistries as well as mixtures thereof, the challenge addressed in this work is formation of materials with specific structure and rigidity. The Lambrecht group develops computational approaches for predicting the contributions of "synthons" on reaction energetics and polymer properties from first principles; computational prediction informs synthesis performed in Pentzer's laboratory by proposing rational modifications, including solvent polarity and counterion choice. The Pentzer group evaluates the impact of experimental conditions on polymerization, synthesizes and characterizes new polymers, and closes the feedback loop by generating empirical data to validate and refine computational approaches of Lambrecht. The research activities include 1) identifying the fundamental reactivity patterns of silyl ketenes as relevant to chain growth polymerization, 2) controlling the formation of well-defined oligomers, and 3) preparing each of the new polymer chemistries individually and establishing their properties and applications. Further, Pentzer and Lambrecht offer annually a two-day workshop on how to successfully combine two relatively siloed areas of research- computation and experiment.
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.