Thermal Field-Flow Fractionation of Nanoscale Materials

Colorado School Of Mines, Golden CO

Investigators

Abstract

With this award, the Chemical Measurement and Imaging Program of the Division of Chemistry is funding Professor Kim Williams of the Colorado School of Mines to develop thermal field-flow fractionation (ThFFF) as a versatile platform for separating and characterizing complex nanoscale materials. Thermal diffusion in liquids is a transport phenomenon that presents fertile ground for developing new measurement capabilities because it is founded on different principles than existing methods. The planned close collaboration with synthesis and engineering groups is ideal for maximizing research impact across different fields. Given the significant rise in the synthesis and application of polymers and organic/inorganic/metallic nanoparticle hybrids in fields such as energy, biomedicine, and coatings, the platform being targeted has significant potential for broad scientific, educational and environmental impact. In addition, an outreach program developed by Professor Williams introduces activities related to nanoscale materials to K-12 teachers of disadvantaged Denver school districts and the Rocky Mountain Camp for Dyslexic children. This project focuses on understanding of the relationship between thermal diffusion and polymer-solvent or nanoparticle-solvent parameters for the purpose of developing thermal field-flow fractionation (ThFFF) as a central tool for the analysis and study of currently intractable systems. Thermal diffusion in liquids continues to represent a fertile ground for developing separations and analyses that are founded on a different basis than existing methods. The proposed work is aimed at enhancing understanding of thermal diffusion and polymer-solvent or nanoparticle-solvent parameters that drive this transport process. Strategic libraries of materials with specifically chosen levels of complexities have been chosen, e.g., polymers with a varying set of controlled backbone lengths, side chain lengths, and grafting densities have been selected in order to enable the Williams research team to identify the main analyte properties that contribute to thermal diffusion in different solvents and to assess existing thermal diffusion theories. The overarching objectives include identifying specific co-polymer architectures and their distributions, assessing thermal diffusion trends of organic and metal hybrid nanoparticles, and demonstrating surface composition-based separations and analyses. The proposed studies are also expected to shed light on which of the prevailing models best describes polymer dynamics and dynamics of polymer systems that are confined.