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Search Publications by: Paul Butler (Fed)

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Displaying 26 - 41 of 41

Kinetic Polymer Arrest in Percolated SWNT Networks

December 3, 2014
Author(s)
Rana NMN Ashkar, Mansour Abdul Baki, Madhu Sudan Tyagi, Antonio Faraone, Paul Butler, Ramanan Krishnamoorti
The inclusion of single-wall carbon nanotubes (SWNT) in a polymer, with interchain distances comparable to the SWNT diameter, can significantly perturb the structural and dynamical properties of interfacial polymeric units. For SWNT concentrations above

Learning About SANS Instruments and Data Reduction from Round Robin Measurements on Samples of Polystyrene Latex

October 1, 2013
Author(s)
Adrian R. Rennie, Maja S. Hellsing, Kathleen Wood, Elliot P. Gilbert, Lionel Porcar, Ralf Schweins, Charles D. Dewhurst, Peter Lindner, Richard K. Heenan, Sarah E. Rogers, Paul Butler, Jeffery R Krzywon, Ron E. Ghosh, Andrew J. Jackson, Marc Malfois
Round-robin measurements of polystyrene latex samples at a number of small-angle scattering facilities have been used to assess the current limits of reliability and reproducibility of scattering data as well as the accuracy of parameters derived from

A Molecular Model for Toughening in Double-Network Hydrogels

June 18, 2008
Author(s)
Vijay Tirumala, Sanghun Lee, Taiki Tominaga, Eric K. Lin, Jian P. Gong, Paul D. Butler, Wen-Li Wu
A molecular mechanism is proposed for the toughness enhancement observed in double network (DN) hydrogels prepared from poly (2 acrylamido, 2-methyl, 1-propanesulfonicacid) (PAMPS) polyelectrolyte network and polyacrylamide (PAAm) linear polymer. It is an

Orientation of Platelets in Multilayered Nanocomposite Polymer Films

December 1, 2003
Author(s)
M M. Malwitz, Sheng Lin-Gibson, Erik K. Hobbie, Paul Butler, G Schmidt
The orientation of platelets in micron thick polymer-clay nanocomposite films was investigated by means of small-angle neutron scattering (SANS), small angle X-ray scattering (SAXS) and wide-angle X-ray diffraction (WAXD). The films with various clay

Small Angle Neutron Scattering From Viscoelastic Polymer-Clay Solutions

January 1, 2002
Author(s)
G Schmidt, A Nakatani, Paul Butler, Charles C. Han
The influence of shear on viscoelastic polymer-clay solutions was investigated by means of small-angle neutron scattering (SANS) under shear. SANS measured the shear-induced orientation of polymer and platelets. With increasing shear rate an anisotropic

Small Angle Neutron Scattering Study on Polymer-Clay Solutions

August 1, 2001
Author(s)
Charles C. Han, G Schmidt, A Nakatani, Paul D. Butler
The objective of this work is to investigate the influence of shear on the structure of a highly viscoelastic, aqueous polymer-clay solution. Many structural models have been proposed for such systems. However, this is the first time to observe the

Polymer-Clay Nanocomposite Materials: Solution and Bulk Properties

January 1, 2001
Author(s)
G Schmidt, A Nakatani, Paul Butler, V Ferreiro, Alamgir Karim, Charles C. Han
The influence of shear on viscoelastic polymer-clay solutions was investigated by means of small-angle neutron scattering (SANS) under shear. SANS measured the shear-induced orientation of polymer and platelets. With increasing shear rate an anisotropic

Shear Orientation of a Visoelastic Polymer-Clay Solution

August 1, 2000
Author(s)
G Schmidt, A Nakatani, Paul Butler, Alamgir Karim, Charles C. Han
The shear orientation of viscoelastic clay-polymer solutions was investigated by means of rheology, flow birefringence (δn) and small-angle neutron scattering (SANS). Oscillatory shear showed a linear viscoelastic region and flow occured at higher stresses