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We demonstrate that thermal wrinkling can be utilized to measure the rubbery modulus and shear viscosity of polystyrene (PS) thin films as a function of temperature. Specifically, we use surface laser-light scattering (SLS) to characterize the wrinkled
Gerald L. Vogel, Livia M. Tenuta, Gary E. Schumacher, Laurence C. Chow
Background: Plaque calcium fluoride or biological/bacterial calcium-fluoride deposits appear to be the source of cariostatic concentrations of fluoride in plaque fluid. Aims: (1) To quantify the amount of plaque calcium fluoride after a NaF rinse. (2) To
Although existing techniques can measure the viscoelastic properties of bulk polymers, few are available for measuring these properties in polymer thin films. This information has become increasingly important as polymers thin films are developed in a
The long-term performance and stability of composites made from renewable feedstocks will be strongly dependent on the inherent viscoelastic relaxation processes of the material. These relaxations are controlled not only by the polymer network structure
Jong Keun Park, Paul J. Jones, Chris Sahagun, Kirt A. Page, Daniel S. Hussey, David L. Jacobson, Sarah E. Morgan, Robert B. Moore
While ionic polymer metal composites (IPMCs) have been studied for more than 10 years, the specific actuation mechanism is still unclear. In this work, neutron imaging, applied potential (AP) and current sensing (CS) atomic force microscopy (AFM) methods
Jan Obrzut, A Anopchenko, Jack F. Douglas, Bert W. Rust
We utilize dielectric relaxation process for the quantitative characterization of antiplasticization of trehalose by glycerol. The high frequency Johari-Goldstein relaxation time was obtained by analyzing the complex permittivity data in terms of the
Ward L. Johnson, Sudook A. Kim, Roy H. Geiss, Colm Flannery, Paul R. Heyliger, Christopher L. Soles, Wen-Li Wu, Chengqing C. Wang, Christopher M. Stafford, B D. Vogt
Elastic constants and cross-sectional dimensions of imprinted nanolines of poly(methyl methacrylate) (PMMA) on silicon are determined nondestructively from finite-element inversion analysis of dispersion curves of hypersonic acoustic modes of these
Michael J. Fasolka, Christopher M. Stafford, Kathryn L. Beers
We present and overview of research conducted at the National Institute of Standards and Technology aimed at developing combinatorial and high throughput measurement approaches to polymer surfaces, interfaces and thin films. Topics include, 1) the
Roland H. Kraemer, Mauro Zammarano, Gregory T. Linteris, Ulf W. Gedde, Jeffrey W. Gilman
Flexible polyurethane foam used in upholstered furniture remains one of the major fire hazards to date. The heat release rate of burning items made of foam depends strongly on the foam's physical behavior, notably its collapse to a burning liquid that can
Santanu S. Kundu, Atul Bhangale, William E. Wallace, Kathleen M. Flynn, Richard Gross, Kathryn L. Beers
Application of microreactor technologies enable improved safety, selectivity and yield in a range of chemical reactions in addition to new measurement methods that are often faster, cheaper and more accurate than traditional methods. In this study we have
Atul Bhangale, Santanu S. Kundu, Wenchun Xie, William E. Wallace, Kathleen M. Flynn, Kathryn L. Beers, Richard Gross
Epoxy functionalized supports are known to be suitable for industrial-scale immobilization of enzymes for biocatalysis. However, chemistry across these epoxy groups is known to affect the catalytic performance of the enzymes.In order to achieve a balance
This work reports on the creation and characterization of nanofiber supported bilayers to mimic the hydrodynamic, chemical and mechanical environment provided by the actin network which supports natural lipid bilayers within a cell. Lipid bilayers were
Carl G. Simon Jr., Murugan Ramalingam, Marian F. Young, Vinoy Thomas
Scaffolds play a key role in tissue engineering wherein they provide structural support for cells to adhere, grow and guide them to synthesize tissue. Scaffolds made of multiple biomaterials are typically required to mimic the three-dimensional (3D)
The National Institute of Standards and Technology (NIST) has deployed Reference Material (RM) scaffolds for tissue engineering: a series of well-characterized 3D tissue scaffolds with differing porosities (RM 8395, RM 8396 and RM 8397) (Fig. 1). Customers
Despite significant investment in tissue engineering research, few profitable products have come to market. Hence, there is a need to accelerate tissue engineering research. One approach to accelerating research is combinatorial and high-throughput (CHT)
Viscoelastic relaxation processes factor into polymer performance and stability throughout an application lifetime. These relaxations are controlled by the polymer network structure and dynamics which occur at different orders of magnitude in time. In most
Naomi Eidelman, A Boyde, A.J. Bushby, P.G.T. Howell, Jirun Sun, F.W. Miller, P Robey, Lisa Rider
Calcified deposits are present in 30% of children with juvenile dermatomyositis (JDM) and less frequently in adult dermatomyositis (DM). This study aimed to determine the microstructure, composition and stiffness of these deposits. Specimens were analyzed
Kirt A. Page, Edwin Chan, Se Hyuk Im, Derek L. Patton, Rui Huang, Christopher Stafford
We present a new measurement technique to quantify the viscoelastic properties of polymer thin films. This approach utilizes thermally-induced surface wrinkling to measure the rubbery modulus and shear viscosity of polymer thin films. Specifically, by
Sang-Won Myoung, James J. Lee, Paul Constantino, Peter Lucas, Brian R. Lawn
Teeth are remarkable biological structures, brittle but resilient. Here we examine the inter-relation between enamel morphology and crack resistance by sectioning human molar teeth after loading to fracture. The sections reveal that many cracks start from
Ernest L. Madsen, G R. Frank, M A. Hobson, Sheng Lin-Gibson, T J. Hall, J Jiang, T A. Stiles
Accurate determination of the complex shear modulus of soft-tissue-like materials in the 10 to 300 Hz frequency range is very important to researchers in MR Elastography and Acoustic Radiation Force Impulse (ARFI) imaging. A variety of instruments for
Sheng Lin-Gibson, Kaushik Chatterjee, James A. Cooper, William E. Wallace, Matthew Becker, Carl G. Simon Jr., Ferenc Horkay
A simple reaction to prepare controlled molecular mass (MM) poly(ethylene glycol) dimethacrylates (PEGDMs) of high purity and low polydispersity is outlined. PEGDMs were photo-polymerized to form hydrogels with and without bioactive moieties. The structure
Sheng Lin-Gibson, Sarah E. Grieshaber, Alexandra J. Farran, Kristi L. Kiick, Xinqiao Jia
We are interested in developing elastin mimetic hybrid polymers (EMHPs) that capture the multiblock molecular architecture of tropoelastin as well as the remarkable elasticity of mature elastin. In this study, multiblock EMHPs containing flexible synthetic
Nancy Lin, Diana N. Zeiger, Joseph M. Antonucci, Bruce O. Fowler, Christopher Stafford, Sheng Lin-Gibson
Controlling bacterial growth in the oral environment presents many challenges. To address these challenges, new materials and treatments are needed along with controlled, reproducible methods to evaluate their efficacy. In this study, a reproducible method