Polymerization Kinetics, Thermodynamics, and Synthesis
under Nanoconfinement
by
Sindee L. Simon
Dept. of Chemical Engineering, Texas Tech University
Lubbock, TX, USA
SEMINAR
Polymerization Kinetics, Thermodynamics, and Synthesis under Nanoconfinement
by
Sindee L. Simon
Dept. of Chemical Engineering, Texas Tech University
Lubbock, TX, USA
at
Dept of Materials Science & Metallurgy,
27 Charles Babbage Road, CB3 0FS
Goldsmiths’ Lecture Room 1
Friday 21 February 2020, 13:15-14:15pm
The behavior of materials confined at the nanoscale has been of considerable interest over the past several decades, especially changes in the glass-transition temperature (Tg) and/or melting point (Tm). Less well studied are the effects of nanoconfinement on polymerization kinetics and thermodynamics. Our recent focus has been on understanding how nanoconfinement influences various classes of polymerizations, including the step-growth reactions of thermosetting resins, the free-radical reaction of various methacrylates, and the ring-opening polymerization of dicyclopentadiene. We find that changes in reaction rates under confinement can generally be explained by a competition between changes in local packing, diffusivity, and surface effects. The result is generally, but not always, an acceleration of the rate of the nanoconfined polymerization. In addition, nanoconfinement influences the chain length, PDI, and tacticity of the synthesized polymer, making confinement a potential tool for controlling synthetic outcomes. Finally, in the case of equilibrium polymerizations, nanoconfinement influences the monomer/polymer equilibrium shifting it back towards monomer, and this effect can be exploited to determine the entropy loss on confining a chain and to test scaling theories in the literature concerning confinement entropy.
Sindee L. Simon - Brief Bio
Prof. Sindee L. Simon obtained a B.S. in Chemical Engineering at Yale University in 1983 and her Ph.D. in Chemical Engineering at Princeton University in 1992. She is currently Horn Professor in the Department of Chemical Engineering at Texas Tech University. Her research interests include the physics of the glass transition, cure and properties of thermosetting materials, and properties and reactivity at the nanoscale. She has published over 120 refereed journal publications, has over 4000 citations, an h-index of 33 according to Web of Science. She has received numerous honors, including Fellowships in the American Physical Society, the Society of Plastics Engineers (SPE), the North American Thermal Analysis Society (NATAS), and the American Institute of Chemical Engineers. She is also the recipient of the 2019 SPE International Award, as well as the SPE Research/Technology Award and the NATAS Outstanding Achievement Award.