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Mark S. Meier
Professor of Chemistry (Organic Chemistry)
Design and Synthesis of Superstrong Materials
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| Our research on super-strength carbon fibers pivots on our ability to selectively functionalize materials (multiwall carbon nanotubes, MWNTs) that are nearly inert to most chemical treatments. The major challenge is the development of methods to activate graphite (cylindrical pieces, but graphite nonetheless) without completely destroying the structure. A second challenge is the characterization of the products of a chemical reaction when the starting material and the product are both heterogeneous, insoluble materials. We and others have shown that we can functionalize MWNTs by oxidation and by electrophilic aromatic substitution, and that evidence for reaction can be found in TGA. We are now focusing on applying these methods to mechanically-milled nanotubes, where the high-aspect ratio (~1:1000) has been reduced to ~1:200. This milling produces more "ends" and therefore more sites for oxidation or for aromatic substitution. Undergraduates will be involved in milling and oxidation of nanotubes, looking for conditions that produce a high degree of carboxylation without unacceptable degradation of the nanotube sections. The carboxylates can then be derivatized to produce a variety of chemically functionalized MWNTs. Students involved in this research get to learn the techniques of organic synthesis, along with analytical techniques that are not commonly used by organic chemists. In addition to traditional IR spectroscopy, we use solid-state NMR, TGA, DSC, DMA (dynamic mechanical analysis) and electron microscopy to characterize our materials and composite made with them. In addition, we work side-by-side with chemical engineers, so students will be able to watch the preparation of composite materials, potentially with some of the materials they have made with their own hands. |
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Further details of Dr. Meier's work are given on the Chemistry website.
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