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Search Publications

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Displaying 51 - 75 of 1847

Simulated stress mitigation strategies in embedded 3D bioprinting

August 30, 2022
Author(s)
Leanne Friedrich, Ross Gunther, Jonathan Seppala
Extrusion-based 3D bioprinting is a powerful tool for fabricating complex cell-laden constructs. Embedded Ink Writing (EIW) is an extrusion-based printing technique wherein a nozzle embedded into a support bath writes continuous filaments. Because it

Leveraging Theory for Enhanced Machine Learning

August 26, 2022
Author(s)
Debra Audus, Austin McDannald, Brian DeCost
The application of machine learning to the materials domain has traditionally struggled with two major challenges: a lack of large, curated data sets and the need to understand the physics behind the machine-learning prediction. The former problem is

Relative effects of polymer composition and sample preparation on glass dynamics

August 17, 2022
Author(s)
Christopher Soles, Amanda L. Forster, Katherine Evans, Madhusudan (Madhu) Tyagi, Robert M. Elder, Timothy Sirk, Joseph Dennis, Kanae Ito, Osama Yamamuro, Hiroshi Akiba
Modern design of common adhesives, composites and polymeric parts makes use of polymer glasses that are stiff enough to maintain their shape under a high stress while still maintaining a ductile behavior after the yield point. Typically, material

Simulation-guided resonant soft X-ray scattering for determining microstructure of triblock copolymers

August 1, 2022
Author(s)
Eliot Gann, Veronica Reynolds, Michael L. Chabinyc, Christopher Bates, Devon Callan, Elizabeth Murphy, Yan-Qiao Chen, Kaitlin Albanese, Claire Wu, Craig Hawker
Resonant soft X-ray scattering (RSoXS) probes structure with chemical sensitivity that is useful for determining the morphology of multiblock copolymers. However, the hyperspectral data produced by this technique are challenging to interpret. Here, we use

Ultrafast stiffening of concentrated thermoresponsive polymer-mineral suspensions

July 21, 2022
Author(s)
Edward Garboczi, Sharu Kandy, Iman Mehdipour, Narayanan Neithalath, Aditya Kumar, Mathieu Bauchy, Samanvaya Srivastava, Torben Gaedt, Gaurav Sant
Extrusion-based 3D printing with rapidly hardening polymeric materials is capable of building almost any conceivable structure. However, concrete, one of the most widely used materials for large-scale structural components, is generally based on inorganic

Suppression of filament defects in embedded 3D printing

July 5, 2022
Author(s)
Leanne Friedrich, Ross Gunther, Jonathan Seppala
Embedded 3D printing enables the manufacture of soft, intricate structures. In the technique, a nozzle is embedded into a viscoelastic support bath and extrudes filaments or droplets. While embedded 3D printing expands the printable materials space to low

Polydimethylsiloxane tissue-mimicking phantoms with tunable optical properties

July 1, 2022
Author(s)
Aaron Goldfain, Paul Lemaillet, David W. Allen, Kimberly Briggman, Jeeseong C. Hwang
We report on techniques to manufacture and characterize solid tissue-mimicking phantoms of polydimethylsiloxane (PDMS) polymers. Tunability of the absorption (a()) and reduced scattering spectra (s'()) in the wavelength range of 500 nm to 850 nm is

Time-gated Raman spectroscopy of recovered plastics

July 1, 2022
Author(s)
Anthony Kotula, Sara Orski, Kayla Brignac, Jennifer Lynch, Bryan Heilala
Raman spectroscopy is a powerful non-destructive technique for the identification and characterization of plastics. The technique often has limited use due to fluorescence emission, which often occurs in polymer samples containing colorants or that have

In-situ studies of the swelling by electrolyte in the electrochemical doping of an ethylene glycol substituted polythiophene

June 13, 2022
Author(s)
Lee J. Richter, Lucas Flagg, Lauren Asselta, Nicholas D'Antona, Natalie Stingelin, Tommaso Nicolini, Jonathan Onorato, Christine Luscombe, Ruipeng Li
Organic mixed ionic electronic conductors (OMIECs) have the potential to enable diverse new technologies, ranging from biosensors to flexible energy storage devices and neuromorphic computing platforms. However, study of these materials in their operating

Coherent anti-Stokes Raman scattering (CARS) microscopy for polymers

April 1, 2022
Author(s)
Shuyu Xu, Charles Camp, Young Jong Lee
Coherent anti-Stokes Raman scattering (CARS) microscopy is a label-free chemical imaging modality capable of interrogating local molecular composition, concentration, and even orientation. In comparison to traditional Raman spectroscopy/imaging, CARS

Resonant X-ray Scattering in Polymer Science

April 1, 2022
Author(s)
Brian Collins, Eliot Gann
Resonant Soft X-ray Scattering (RSoXS) is an emerging, powerful technique to probe the nano-to-mesoscale ordering of polymers and other molecules. It joins together small-angle X-ray scattering (a statistical nanoprobe) with X-ray spectroscopy that brings

A small-volume microcapillary rheometer

March 30, 2022
Author(s)
Paul Salipante, Steve Kuei, Steven Hudson
We demonstrate a capillary device used to measure the shear rate dependent viscosity of microliter scale volumes. Liquid samples are driven pneumatically to fill a microcapillary and partially fill a larger glass capillary. The glass capillary is mounted

Reassessing the Significance of Reduced Aggregation and Crystallinity of Naphthalene Diimide-Based Copolymer Acceptors in All-Polymer Solar Cells

March 28, 2022
Author(s)
Eliot Gann, Christopher McNeill, Doan Vu, Martyn Jervic, Chao Wang, Lars Thomsen, Mats Andersson
Terpolymerization is a facile and effective strategy to control the aggregation and crystallinity of semiconducting polymers which has been exploited to improve the photovoltaic performance of all-polymer solar cells (all-PSCs). Applying this strategy to

Effects of Thermal Aging on Molar Mass of Ultra-High Molar Mass Polyethylene Fibers

March 24, 2022
Author(s)
Zois Tsinas, Sara Orski, Viviana Bentley, Lorelis Gonzalez-Lopez, Mohamad Al-Sheikhly, Amanda L. Forster
Ultra-high molar mass polyethylene (UHMMPE) is commonly used for ballistic-resistant body armor applications due to the superior strength of the fibers fabricated from this material combined with its low density. However, polymeric materials are

Chapter: Structure and phase behavior of polyampholytes and polyzwitterions

March 4, 2022
Author(s)
Phillip Pickett, Yuanchi Ma, Vivek Prabhu, Michael Lueckheide, Nicholas Posey
Polyelectrolytes contain many units of charged moieties, often as either anionic or cationic. However, when a polymer comprises both anionic and cationic monomers, the result is a polyampholyte. Polyzwitterions are a type of polyampholyte that contain

Computational Design of Helical Peptide Bundle Variants Spanning a Wide Range of Charge States

March 1, 2022
Author(s)
Jeffrey Fagan, Nairiti Sinha, rui gui, Darrin Pochan, Grethe Vestergaard Jensen, Jeffery Saven, matthew Langenstein, Rajkumar Misra, Christopher Kloxin, yan tang
Peptides can be computationally designed and engineered to achieve various functionalities and structures. Herein computational design was used to identify a set of 17 peptides having a wide range of putative charge states but the same tetrameric coiled
Displaying 51 - 75 of 1847