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Search Publications by: Chad R. Snyder (Fed)

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Displaying 26 - 50 of 80

Structure, Nanomechanics and Dynamics of Dispersed Surfactant-Free Clay Nanocomposite Films

February 22, 2018
Author(s)
Xiao Zhang, Jing Zhao, Chad R. Snyder, Abdullah Al-Enizi, Ahmed Eltazahry, Alamgir Karim
Using additives to tailor the performance of polymeric materials is perhaps one of the most important aspects for producing materials of advanced applications. The exploitation of nanoparticle dispersion strategies have been broadly investigated for tuning

Raman Identification of Multiple Melting Peaks of Polyethylene

August 1, 2017
Author(s)
Ying Jin, Anthony P. Kotula, Chad R. Snyder, Angela R. Hight Walker, Kalman D. Migler, Young J. Lee
Multiple melting peaks of high-density polyethylene produced by complex thermal pre-treatment are investigated with variable temperature Raman spectroscopy and differential scanning calorimetry (DSC). We examine the origin of the observed multiple melting

The dependence of electrical performance on structural organization in low mobility polymer field effect transistors

April 16, 2017
Author(s)
Emily G. Bittle, Hyun W. Ro, Chad R. Snyder, Sebastian Engmann, Regis J. Kline, Oana Jurchescu, Dean M. DeLongchamp, David J. Gundlach
Polymer semiconductors are contenders for use in printed, flexible electronics. Though organic electronic materials have been studied for many years, the physics of charge transport is still under investigation. This is in part due to the large variability

Reduced Bimolecular Recombination in Blade-Coated, High-Efficiency, Small-Molecule Solar Cells

March 22, 2017
Author(s)
Sebastian Engmann, Hyun W. Ro, Andrew A. Herzing, Dean M. DeLongchamp, Chad R. Snyder, Lee J. Richter, Adam J. Barito, David J. Gundlach
The full benefit of emerging solution deposited photovoltaic devices requires development of processes compatible with high speed manufacturing. Extensive studies of the lab-to-fab challenge have been performed on polymer donor based organic photovoltaics

Structure and Order in Organic Semiconductors

January 17, 2017
Author(s)
Chad R. Snyder, Dean M. DeLongchamp, Ryan C. Nieuwendaal, Andrew A. Herzing
Several techniques for characterizing semiconducting polymer order on different length scales are presented, including (1) differential scanning calorimetry (DSC), (2) solid state nuclear magnetic resonance spectroscopy (NMR), (3) transmission electron

Film morphology evolution during solvent vapor annealing of highly efficient small molecule donor/acceptor blends

September 15, 2016
Author(s)
Sebastian Engmann, Hyun W. Ro, Andrew Herzing, Chad R. Snyder, Lee J. Richter, Paul Geraghty, David Jones
Solution-processable small molecule photovoltaics based on the novel molecular donor, benzodithiophene terthiophene rhodamine (BTR), recently have shown maximum power conversion efficiencies above 8% for active layer thicknesses up to 400 nm, using post

Phase Behavior of Poly(3-hexylthiophene-2,5-diyl)

March 8, 2016
Author(s)
Chad R. Snyder, Enrique Gomez
The phase behavior of many conjugated polymers is rich but not yet fully explored. Stiff chain conformations and planar ring-like structures can promote both crystalline and liquid crystalline phases. Recent computational efforts that rely on atomistic and

Bottom Up Approaches to Improved Polyolefin Measurements

February 4, 2016
Author(s)
Sara Orski, Thomas W. Rosch, Anthony Kotula, Richard J. Sheridan, Frederick R. Phelan Jr., Kalman Migler, Chad R. Snyder, Luis F. Vargas Lara, Jack F. Douglas, Kathryn L. Beers
As a class of materials, polyolefins remain the largest production volume polymer in the world, as well as a highly desirable medium from which to engineer high performance and advanced properties for new applications. After decades of research, there are

Classification of Semiconducting Polymeric Mesophases to Optimize Device Post-Processing

August 17, 2015
Author(s)
Chad R. Snyder, Regis J. Kline, Dean M. DeLongchamp, Ryan C. Nieuwendaal, Lee J. Richter, Martin Heeney, Iain McCulloch
Semiconducting polymers form a variety of phases and mesophases that respond differently to post-deposition solvent or thermal treatments. Here it is shown that classification of these materials into their appropriate mesophases can be a useful tool to

Characterization of clay composite ballistic witness materials

July 29, 2015
Author(s)
Jonathan E. Seppala, Yoonae Heo, Paul E. Stutzman, John R. Sieber, Chad R. Snyder, Kirk D. Rice, Gale A. Holmes
Mechanical and thermal properties of Roma Plastilina Clay #1 (RP1) were studied through small-amplitude oscillatory shear (SAOS), large-amplitude oscillatory shear (LAOS), and differential scanning calorimetry (DSC), supplemented with thermogravimetric

In-situ Characterization of Polymer-Fullerene Bilayer Stability

January 8, 2015
Author(s)
Lee J. Richter, Regis J. Kline, Hyun Wook Ro, Chad R. Snyder, Andrew A. Herzing, Sebastian Engmann
A consensus is emerging that every phase present in a bulk heterojunction organic photovoltaic (OPV) device is not material pure. In general, there will exist at least one region characterized by a mixture of donor and acceptor. Significant insights into

Quantifying Crystallinity in High Molar Mass Poly(3-hexylthiophene)

June 3, 2014
Author(s)
Chad R. Snyder, Ryan C. Nieuwendaal, Dean M. DeLongchamp, Christine K. Luscombe, Prakash Sista, Shane D. Boyd
We extend a recent comprehensive study of 3-hexylthiophene oligomers to high molar mass poly(3-hexylthiophene) (P3HT) fractions, such as those used in organic photovoltaic devices. Through a combination of differential scanning calorimetry (DSC) and 13C

Measuring order in regioregular poly(3-hexylthiophene) with solid-state 13C CPMAS NMR

January 10, 2014
Author(s)
Ryan C. Nieuwendaal, Chad R. Snyder, Dean M. DeLongchamp
We report on details of molecular packing in high molar mass poly(3-hexylthiophene) (P3HT) by solid-state 13C {1H} cross-polarization magic angle spinning (CPMAS) NMR measurements. The degree of polymer order was estimated for two films of varied drying

Polymer chain dynamics in weakly intercalated polymer/nanoplatelet mixtures

March 15, 2013
Author(s)
Kevin A. Masser, Hongyi Yuan, Chad R. Snyder, Alamgir Karim
The dynamics of two chemically similar type-A polymers, poly(epsilon-caprolactone) (PCL) and poly(lactic acid) (PLA) with small amounts of Cloisite 30B nanoplatelets were investigated via broadband dielectric relaxation spectroscopy. The terminal

Polymer-Fullerene Mixing in Organic Solar Cells

August 2, 2012
Author(s)
Hyun Wook Ro, Bulent Akgun, Regis J. Kline, Chad R. Snyder, Sushil K. Satija, Christopher L. Soles, Dean M. DeLongchamp, Michael F. Toney, Alexander L. Ayzner, Brendan T. O'Connor, Matthew Hammond
The mixing behavior of the hole and electron transporting materials in bulk heterojunction (BHJ) organic photovoltaic (OPV) blends plays a key role in determining the nanoscale morphology, which is believed to be a decisive factor in determining device

Time dependent CO2 sorption hysteresis in a one-dimensional microporous octahedral molecular sieve

April 6, 2012
Author(s)
Laura Espinal, Winnie K. Wong-Ng, Andrew J. Allen, Daniel W. Siderius, Chad R. Snyder, Eric J. Cockayne, Lan (. Li, James A. Kaduk, Anais E. Espinal, Steven L. Suib, Chun Chiu
A critical challenge in the development of novel carbon capture materials with engineered porous architectures is to understand and control the phenomenon of sorption hysteresis, whereby the path to adsorption of gas molecules by the porous host differs

Effect of Regioregularity on the Semicrystalline Structure of Poly(3-hexylthiophene

August 25, 2011
Author(s)
Chad R. Snyder, Dean M. DeLongchamp, Jessica S. Henry
The impact of regioregularity in poly(3-hexylthiophene-2,5-diyl) (P3HT) on crystallization behavior and quantitative limits to possible crystal sizes is discussed, and it is explained why regioregularities must be reported for any study to be properly

Influence of substrate on crystallization in polythiophene/fullerene blends

January 13, 2011
Author(s)
Lee J. Richter, Christine He, David Germack, R Joseph Kline, Dean DeLongchamp, Daniel A. Fischer, Chad R. Snyder, James G. Kushmerick
The nanoscale morphology of the active layer in organic, bulk heterojunction (BHJ) solar cells is crucial to device performance. Often a combination of casting conditions and post deposition thermal treatment are used to optimize the morphology. In general