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Search Publications

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Displaying 76 - 100 of 1848

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

Life Cycle Environmental Impacts of Plastics: A Review

March 1, 2022
Author(s)
Paul Rikhter, Ilayda Dinc, Yirui Zhang, Ted Jiang, Bobby Miyashiro, Shelby Walsh, Ruoyu Wang, Yvonne Dinh, Sangwon Suh, Joshua D. Kneifel
Global production and consumption of plastics and its deposition in the environment are growing rapidly, while their life-cycle impacts to the environment are yet to be fully understood. This study reviews the existing literature with the goal of

Imaging 3D molecular orientation by orthogonal-pair polarization IR microscopy

February 28, 2022
Author(s)
Shuyu Xu, Chad R. Snyder, Jeremy Rowlette, Young Jong Lee
Anisotropic molecular alignment occurs ubiquitously and often heterogeneously in three dimensions (3D). However, conventional imaging approaches based on polarization can map only molecular orientation projected onto the 2D polarization plane. Here, an

Pruning the Mechanical Impedance of Three-Dimensional Disordered Networks

February 21, 2022
Author(s)
Marcos Reyes-Martinez, Edwin P. Chan, Christopher Soles, Michael A. Riley, Endao Han, Nidhi Pashine, Kieran Murphy, Heinrich Jaeger, Sidney Nagel, Daniel Reid, Meng Shen, Juan J. de Pablo
Disordered networks, comprised of random arrangements of bonds and nodes, have emerged as materials with the unique ability for independent control over the shear and bulk moduli. Recent computational studies have demonstrated that an extremely high degree

A method to quantify composition, purity, and cross-link density of the polyamide active layer in reverse osmosis composite membranes using 13C cross-polarization magic angle spinning nuclear magnetic resonance spectroscopy

February 12, 2022
Author(s)
Ryan Nieuwendaal, Christopher Stafford, Jeff Wilbur
A method for harvesting and purifying the thin polyamide (PA) active layer from thin-film composite (TFC) reverse osmosis (RO) membranes was developed, enabling quantitative nuclear magnetic resonance (NMR) measurements of the composition and cross-linking

Interface History on Strain Field Evolution in Epoxy Resins

January 21, 2022
Author(s)
Edward Garboczi, Newell Moser, Jena McCollum, Jared Strutton, Abby Jennings, Brandon Runnels
To determine the viability of digital image correlation in the analysis of additively manufactured thermosets, we devised a testing method to examine the effect of interface history (i.e., time between interface formation and original material deposition)

Predicting the plateau modulus from molecular parameters of conjugated polymers

January 18, 2022
Author(s)
Abigail Fenton, Renxuan Xie, Melissa Aplan, Youngmin Lee, Michael Gill, Ryan Fair, Fabian Kempe, Michael Sommer, Chad R. Snyder, Enrique Gomez, Ralph Colby
The relationship between Kuhn length lk, Kuhn monomer volume v0, and plateau modulus GN0 , initially proposed by Graessley and Edwards for flexible polymers, and extended by Everaers, has a large gap in experimental data between the flexible and stiff

Non-fullerene acceptors with direct and indirect hexa-fluorination afford > 17% efficiency in polymer solar cells

December 22, 2021
Author(s)
Subhrangsu Mukherjee, Guoping Li, Liang-Wen Feng, Leighton Jones, Robert Jacobberger, Wei Huang, Ryan Young, Robert Pankow, Weigang Zhu, Norman Lu, Kevin Kohlstedt, Vinod Sangwan, Michael Wasielewski, Mark Hersam, George Schatz, Dean DeLongchamp, Antonio Facchetti, Tobin Marks
The rational molecular design of non-fullerene acceptors (NFAs) in organic solar cells (OSCs) can profoundly influence the photovoltaic (OPV) performance. To date, NFA fluorination has proven beneficial to cell performance. However, there is a lack of

Orientation of Thin Polyamide Layer-by-Layer Films on Non-Porous Substrates

December 16, 2021
Author(s)
Tawanda J. Zimudzi, Sarah E. Sheffield, Kathleen E. Feldman, Peter Beaucage, Dean DeLongchamp, Douglas I. Kushner, Christopher Stafford, Michael A. Hickner
The orientation of polyamide thin films on non-porous substrates was investigated using Fourier transform infrared (FTIR) spectroscopy and corroborated by near edge X-ray absorption fine structure (NEXAFS) measurements. Polyamide films comprised of m

Thermal Shrinkage Reveals the Feasibility of Pulse-delay Photocuring Technique

December 1, 2021
Author(s)
Sri Vikram Palagummi, Taeseung Hong, Li Jiang, Martin Chiang
Objectives: To resolve applicability of the pulse-delay photocuring technique to restorative dental composites as a clinical strategy for the reduction in the detrimental polymerization stress. Methods: Model dental composites with high and low-filler

Systematically Controlling Acceptor Fluorination Optimizes Hierarchical Morphology, Vertical Phase Separation, and Efficiency in Non-Fullerene Organic Solar Cells

November 21, 2021
Author(s)
Guoping Li, Xiaohua Zhang, Subhrangsu Mukherjee, Wei Huang, Ding Zheng, Liang-Wen Feng, Yao Chen, Jianglin Wu, Vinod Sangwan, Mark Hersam, Dean DeLongchamp, Junsheng Yu, Antonio Facchetti, Tobin Marks
Non-fullerene acceptor (NFA) end group (EG) functionalization, especially by fluorination, affects not only the energetics but also the morphology of bulk-heterojunction (BHJ) organic solar cell (OSC) active layers, thereby influencing the power conversion

Activation of Mechanophores in a Thermoset Matrix by Instrumented Scratch

November 17, 2021
Author(s)
Chelsea S. Davis, Jeremiah Woodcock, Ryan Beams, Mitchell Rencheck, Muzhou Wang, Stephan J. Stranick, Aaron M. Forster, Jeffrey Gilman
Scratches in polymer coatings and barrier layers negatively impact optical properties (haze, light transmission, etc.), initiate routes of degradation or corrosion (moisture permeability), and nucleate delamination of the coating. Detecting scratches in

Solvent-cast 3D Printing of Biodegradable Polymer Scaffolds

October 22, 2021
Author(s)
John Tolbert, Diana Hammerstone, Nathaniel Yuchimiuk, Jonathan Seppala, Lesley Chow
Three-dimensional (3D) printing is a popular technique to fabricate scaffolds for tissue engineering because of its ability to produce complex tissue-like architectures. Scaffolds are often 3D printed using biodegradable polymers like poly(caprolactone)

Imperfect Surface Order and Functionalization in Vertical Carbon Nanotube Arrays Probed by Near Edge X-ray Absorption Fine Structure Spectroscoy (NEXAFS)

October 12, 2021
Author(s)
T Hemraj-Benny, S Banerjee, S Sambasivan, Daniel A. Fischer, G Eres, Alexander Puretzky, David B. Geohegan, D H. Lowndes, J A. Misewich, S S. Wong
Probing surface order in nanotube systems is of fundamental importance for incorporation of these materials into practical electronic devices. The current study pertains to analysis of the surface orientation of vertically aligned single-walled and multi

Measuring Tie Chains and Trapped Entanglements in Semicrystalline Polymers

September 21, 2021
Author(s)
Amanda G. McDermott, Paul DesLauriers, Jeff Fodor, Ronald L. Jones, Chad R. Snyder
A label-free method for quantifying stress-transmitter (or elastically effective molecule) content (p) in semicrystalline polymers, including both tie molecules and bridging entanglements, is developed and demonstrated based on swelling with deuterated

Side Chain Engineering Control of Mixed Conduction in Oligoethylene Glycol-Substituted Polythiophenes

August 31, 2021
Author(s)
Jonathan Onorato, Zhongyang Wang, Yangyang Sun, Christian Nowak, Ban Dong, Lucas Flagg, Ruipeng Li, Lee J. Richter, Fernando Escobedo, Paul Nealey, Shrayesh Patel, Christine Luscombe
A major limitation for polymeric mixed ionic/electronic conductors (MIECs) is the trade-off between ionic and electronic conductivity; changes made that improve one typically hinder the other. In order to address this fundamental problem, this work

Polarized X-ray scattering measures molecular orientation in polymer-grafted nanoparticles

August 12, 2021
Author(s)
Subhrangsu Mukherjee, Dean DeLongchamp, Eliot Gann, Daniel Sunday, Lee J. Richter, Jason Streit, Richard A. Vaia, Baskar Ganapathysubramanian, Kumar Saurabh, Adarsh Krishnamurthy
Polymer chains are attached to nanoparticle surfaces for many purposes, including altering solubility, influencing aggregation, dispersion, and even tailoring immune responses in drug delivery. The most unique structural motif of polymer-grafted
Displaying 76 - 100 of 1848