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Displaying 126 - 150 of 1852

Polyvinyl Acetate-Based Polymer Host for Optical and Far-Infrared Spectroscopy of Individualized Nanoparticles

January 15, 2021
Author(s)
Jeffrey Fagan, Henry Wladkowski, Julian Duarte, Shashank R. Nandyala, Joshua Walker, Subash Kattel, Jeffrey Blackburn, Jon Pikal, William D. Rice
Preparation techniques for producing films of individualized, solution dispersed nanoparticles (NPs) for optical spectroscopy are often technically challenging and tailored for a specific NP system. In this work, we present a rapid, easy, and economical

Confinement and Processing Can Alter the Morphology and Periodicity of Bottlebrush Block Copolymers in Thin Films

December 22, 2020
Author(s)
Daniel Sunday, Moshe Dolejsi, Alice B. Chang, Lee J. Richter, Ruipeng Li, Paul Nealey, Robert H. Grubbs
Bottlebrush block copolymers (BBCPs) are intriguing architectural variations on linear BCPs with highly tunable structure. Confinement can have a significant impact on polymer assembly, giving rise to changes in morphology, assembly kinetics, and properties

Methods for Characterization of Bioactivity Using Confocal Microscopy

December 1, 2020
Author(s)
Jirun Sun, Nancy Lin, Joy Dunkers, Sheng Lin-Gibson
One common tissue engineering approach for regenerating or replacing damaged tissues involves a porous polymeric scaffold. The scaffolds serve as the mechanical framework for cell attachment and growth, and generate an environment with features that span

A low-swelling, polymeric mixed conductor operating in aqueous electrolytes

November 30, 2020
Author(s)
Lee J. Richter, Tommaso Nicolini, Jokubas Surgailis, Achileas Savva, Guillaume Wantz, Olivier Dautel, Georges Hadiziioannou, Natalie Stingelin
Organic mixed conductors find use in batteries, bioelectronics technologies, neuromorphic computing and sensing. While great progress has been achieved, polymer-based mixed conductors frequently experience significant volumetric changes during ion uptake

Materials Combining Asymmetric Pore Structures with Well-Defined Mesoporosity for Energy Storage and Conversion

November 25, 2020
Author(s)
Sarah Hesse, Kevin Fritz, Peter A. Beaucage, R. Paxton Thedford, Fei Yu, Francis Disalvo, Jin Suntivich, Ulrich Wiesner
Porous materials design often faces a trade-off between the requirements of high internal surface area and high reagent flux. Inorganic materials with asymmetric/hierarchical pore structures or well-defined mesopores have been tested to overcome this trade

Spectroscopic and Spectrometric Approaches for Assessing the Composition of Embedded Metals in Tissues

November 24, 2020
Author(s)
Steven D. Hudson, Diane E. Smith, Todor Todorov, Adrian P. Defante, Jessica F. Hoffman, John F. Kalininch, Jose A. Centeno
Many medical devices contain metals that interface with the body. Additionally, embedded metal fragments from military wounds are typically not removed, to avoid the risk of morbidity associated with invasive surgery. The long-term health consequences of

Calibration Procedures for Orthogonal Superposition Rheology

November 18, 2020
Author(s)
Ran Tao, Aaron M. Forster
Orthogonal superposition (OSP) rheology is an advanced rheological technique that involves superimposing a small-amplitude oscillatory shear deformation orthogonal to a primary shear flow. This technique allows the measurement of structural dynamics of

EFFECTS OF PRE-STRAIN ON THE NON-LINEAR VISCOELASTIC PROPERTIES OF A MODEL SEALANT

November 18, 2020
Author(s)
Christopher C. White, Donald L. Hunston, Kar tean Tan
The non-linear viscoelastic properties of a model sealant were measured using stress relaxation tests conducted at different strain levels, x. Some specimens were measured with no previous strain history while others were given a preconditioning that

Estimating the Impact of 16 CFR Part 1633 on Bed Fire Outcomes

November 18, 2020
Author(s)
Stanley W. Gilbert, David Butry, Rick D. Davis, Richard Gann
Effective July 1, 2007, the U.S. Consumer Product Safety Commission promulgated a standard to severely reduce the heat release rate and the early heat output from mattresses and foundations when ignited by a flaming ignition source. This study estimates

AMB2018-03: Benchmark Physical Property Measurements for Material Extrusion Additive Manufacturing of Polycarbonate

October 29, 2020
Author(s)
Daniel P. Cole, Frank Gardea, Todd C. Henry, Jonathan Seppala, Edward Garboczi, Kalman D. Migler, Christopher M. Shumeyko, Jeffery R. Westrich, Sara Orski, Jeffery L. Gair
Material extrusion (MatEx) is finding increasing applications in additive manufacturing of thermoplastics due to the ease of use and the ability to process disparate polymers. Since part strength is anisotropic and frequently deviates negatively with

Correlation of Nano-morphology with Structural and Spectroscopic Studies in Organic Solar Cells

October 27, 2020
Author(s)
Eliot Gann, Christopher McNeill, Wenchao Huang, Dinesh Kabra, Urvashi Bothra, Nakul Jain, Amelia C. Liu
The nano-morphology of bulk heterojunction blends based on poly[[4,8-bis[(2- ethylhexyl)oxy]benzo[1,2-b:4,5- b']dithiophene-2,6-diyl][3-fluoro-2-[(2-ethylhexyl)carbonyl]thieno[3,4-b]thiophenediyl]] (PTB7) blended with [6,6]- phenyl-C71-butyric acid methyl

Percolation implications in the rheology of crystallization

October 26, 2020
Author(s)
Anthony P. Kotula, Kalman D. Migler
The rheology of polymer crystallization is an old problem that often defies explanation due to the complex interrelationships between crystallization and flow properties. Although separate measurements of rheology and crystallinity can give some

Rheology of Crystallizing LLDPE

October 8, 2020
Author(s)
Marat Andreev, David Nicholson, Anthony Kotula, Jonathan D. Moore, Jaap Den Doelder, Gregory C. Rutledge
Polymer crystallization occurs in many plastic manufacturing processes, from injection molding to film blowing. Linear low-density polyethylene (LLDPE) is one of the most commonly processed polymers, wherein the type and extent of short chain branching

Effects of Environmental Temperature and Humidity on the Geometry and Strength of Polycarbonate Specimens Prepared by Fused Filament Fabrication

October 3, 2020
Author(s)
Lichen Fang, Yan Yishu, Ojaswi Agarwal, shengyu Yao, Jonathan Seppala, Sung Hoon Kang
It is widely known that the printing quality of fused filament fabrication (FFF) is heavily affected by environmental temperature and humidity, as the case of warping and porosity. However, there is little understanding about the quantitative relations
Displaying 126 - 150 of 1852