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Search Publications by: Christopher Stafford (Fed)

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Displaying 176 - 200 of 394

Quantitative Subsurface Contact Resonance Force Microscopy of Model Polymer Nanocomposites

March 16, 2011
Author(s)
Jason P. Killgore, Jennifer Y. Kelly, Christopher M. Stafford, Michael J. Fasolka, Donna C. Hurley
We present experimental results on the use of quantitative contact resonance force microscopy (CR-FM) for mapping the planar location and depth of 50 nm silica nanoparticles buried beneath polystyrene films 30 nm to 165 nm thick. The presence of shallowly

Flexure-induced structural and electronic changes in polymer supported membranes of length purified single-wall carbon nanotubes

February 22, 2011
Author(s)
John M. Harris, Ganjigunte R. Iyer, Daneesh O. Simien, Jeffrey Fagan, JiYeon Huh, Jun Y. Chung, Steven Hudson, Jan Obrzut, Jack F. Douglas, Christopher Stafford, Erik K. Hobbie
Thin membranes of length purified single-wall carbon nanotubes (SWCNTs) are uniaxially compressed by depositing them on prestretched polymer substrates. Upon release of the strain, the topography, microstructure and conductivity of the films are

Effect of interfaces and adhesion on the creep compliance of thin polymer coatings

February 13, 2011
Author(s)
Peter M. Johnson, John A. Howarter, Christopher Stafford
Thin film indentation experiments on viscoelastic materials allowed for the deconvolution of the bulk compliance from interfacial responses at the buried interface. This technique could discriminate both large changes in the interfacial strength due to

Manipulation of adhesion via sub-surface patterning

February 13, 2011
Author(s)
John A. Howarter, Peter M. Johnson, Jun Y. Chung, Christopher Stafford
The delamination characteristics of patterned and hierarchical interfaces are of great interest due to the advanced adhesion capabilities found with many biological surfaces. Using nature-inspired design principles, micro- and nanostrucutred surfaces have

OCT For Depth Detection of Buried Particles in Polymeric Materials

February 13, 2011
Author(s)
Robert C. Chang, Anant Agrawal, Peter M. Johnson, Christopher Stafford
In this work, we demonstrate a method to produce novel optical phantoms usable for the characterization of OCT axial resolution and contrast. By varying the diameter of the microspheres and the thickness of the polymer layers, different spatial frequencies

System-independent assessment of OCT axial resolution with a bar chart phantom

February 10, 2011
Author(s)
Robert C. Chang, Jeeseong Hwang, Christopher M. Stafford, Anant Agrawal, T. Joshua Pfefer, Megan Connors
We present a novel optical phantom approach for the characterization of OCT axial resolution and contrast via multilayered “bar charts.” We explored two methods to fabricate these phantoms: the first is based on a combinatorial methods approach from

Comment on Viscoelastic properties of con ned polymer lms measured via thermal wrinkling by Edwin P. Chan, Kirt A. Page, Se Hyuk Im, Derek L. Patton, Rui Huang and Christopher M. Stafford, Soft Matter (Communications), 5, 4638 4641 (2009).

January 11, 2011
Author(s)
Paul A. O'Connell, Greg B. McKenna, Edwin Chan, Christopher Stafford
Recently Chan et al. published a paper describing a method to use the wrinkling of a thin elastic film on which is adhered a thin polymer film to extract the viscoelastic properties of the polymer. Results were presented for the rubbery plateau modulus and