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Search Publications by: Anthony Kotula (Fed)

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Displaying 26 - 50 of 57

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

Precision, Tunable Deuterated Polyethylene via Polyhomologation

July 22, 2019
Author(s)
Wesley Farrell, Sara Orski, Anthony Kotula, Kathryn Beers, Daniel Baugh
Polyhomologation (also known as "C1 polymerization") of a deuterated ylide has been performed, which yields linear polyethylene of high deuterium content. Copolymerization with the protonated analog allows for the preparation of sta-tistical copolymers, in

Measuring & Predicting Crystal Morphology in Fused Deposition Modeling

June 19, 2019
Author(s)
Claire McIlroy, Jonathan Seppala, Anthony Kotula
Semi-crystalline polymer melts are commonly used in fused deposition modeling. Although flows have a profound effect on polymer crystallization, the relationship between typical fused deposition modeling (FDM) deformation rates and printed-part crystal

Polymer Additive Manufacturing: Confronting Complexity

June 19, 2019
Author(s)
Anthony P. Kotula, Jonathan E. Seppala, Chad R. Snyder
Since its development and commercialization in the 1980s, polymer additive manufacturing (AM) has become a disruptive technology. In this chapter we describe the ever-increasing demands for polymer AM in industry, academia, and government, as well as the

Preface

June 19, 2019
Author(s)
Jonathan E. Seppala, Anthony P. Kotula, Chad R. Snyder

Flow-induced crystallization during materials extrusion additive manufacturing

September 10, 2018
Author(s)
Lily Northcutt, Sara Orski, Kalman D. Migler, Anthony Kotula
Material extrusion additive manufacturing processes force molten polymer through a printer nozzle at high (> 100 s-1) wall shear rates prior to cooling and crystallization. These high shear rates can lead to flow-induced crystallization in common polymer

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 rheo-Raman microscope: Simultaneous chemical, conformational, mechanical, and microstructural measures of soft materials

October 4, 2016
Author(s)
Anthony P. Kotula, Matthew Meyer, Francesca De Vito, Jan Plog, Angela R. Hight Walker, Kalman D. Migler
We describe the design and demonstrate performance of an instrument capable of simultaneous Raman spectroscopy, rheology, and optical microscopy of materials. The instrument couples a Raman microscope with a rotational rheometer through an optically