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Updated: Sep 21, 2025

Surface Properties of Synthesized Nanoporous Carbon and Silica Matrices
Published on: March 27, 2019
Unraveling the Molecular Weight Dependence of Interfacial Interactions in Poly(2-vinylpyridine)/Silica Nanocomposites
Dmitry N Voylov1,2, Adam P Holt3,4, Benjamin Doughty3,4
1Department of Chemistry and ‡Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37916-1600, United States.
Abstract:
The structure and polymer-nanoparticle interactions among physically adsorbed poly(2-vinylpyridine) chains on the surface of silica nanoparticles (NPs) were systematically studied as a function of molecular weight (MW) by sum frequency generation (SFG) and X-ray photoelectron (XPS) spectroscopies. Analysis of XPS data identified hydrogen bonds between the polymer and NPs, while SFG evaluated the change in the number of free OH sites on the NP's surface. Our data revealed that the hydrogen bonds and amount of the free -OH sites have a significant dependence on the polymer's MW. These results provide clear experimental evidence that the interaction of physically adsorbed chains with nanoparticles is strongly MW dependent and aids in unraveling the microscopic mechanism responsible for the strong MW dependence of dynamics of the interfacial layer in polymer nanocomposites.
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