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The Significance of Percolation on the Dynamics of Polymer Chains Bound to Carbon Black
Published
Author(s)
A Nakatani, R Ivkov, P Papanek, C L. Jackson, H Yang, L T. Nikiel, M Gerspacher
Abstract
Neutron time-of-flight (TOF) spectroscopy is used to compare the chain dynamics of pure polyisoprene with polyisoprene bound to the surface of various grades of carbon black fillers. The carbon black is compounded into the polyisoprene at various initial concentrations. By Soxhlet solvent extraction of the polyisoprene/carbon black compounds, the unbound polymer is removed and samples containing only polyisoprene bound to the carbon black surface are obtained. Two types of dynamics behavior of the polymer chains are observed. At low initial carbon black concentrations, the vibrational density-of-states spectrum of the bound polymer is nearly identical to the spectrum of the pure polymer. However, at higher initial carbon black concentrations, the vibrational density-of-states spectrum of the bound polymer is enhanced over the pure polyisoprene, indicating the bound polymer has a different distribution of vibrational motions than the unbound polymer. The transition between the two types of dynamics may be related to the different percolation concentrations of the carbon blacks used in this study. Models are proposed to explain the dynamic behavior.
Proceedings Title
Filled and Nanocomposite Polymer Materials, Symposium KK | | Filled and Nanocomposite Materials | Materials Research Society
Nakatani, A.
, Ivkov, R.
, Papanek, P.
, Jackson, C.
, Yang, H.
, Nikiel, L.
and Gerspacher, M.
(2001),
The Significance of Percolation on the Dynamics of Polymer Chains Bound to Carbon Black, Filled and Nanocomposite Polymer Materials, Symposium KK | | Filled and Nanocomposite Materials | Materials Research Society, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=852819
(Accessed October 29, 2025)