Event
MSE Seminar: Dr. Kendra Erk, Purdue University
Wednesday, September 13, 2023
3:30 p.m.
Kay Boardrooms, 1107/1109 Kim Engineering Building
Sherri Tatum
301-405-5240
statum12@umd.edu
From Baby Diapers to Bridge Decks: Using Polymer Science to Improve Concrete
Abstract: Polymer hydrogels have many uses, from injectable drug-delivery and self-healing materials to the superabsorbent particles used in baby diapers and as soil additives. This presentation will describe the design and use of hydrogel particles as internal curing agents in high-performance concrete. These particles release water as the cement cures, preventing self-desiccation and increasing the concrete’s strength, durability, and service life. Over the past decade, we have conducted experiments at Purdue using custom synthesized hydrogel particles to determine the relationship between the chemical and physical structures of the hydrogels and their overall internal curing performance. Construction practitioners commonly assume that hydrogel internal curing agents are chemically inert within concrete mixtures. However, our more recent results have shown that instead, the presence of hydrogel particles of certain compositions – including acrylamide-rich particles and composite particles containing silica – encourages the formation of high-strength inorganic phases within the cement microstructure, thus forming a more dense and durable concrete. We have also shown that the presence of multivalent cations that naturally occur in hydrating cement actually decreases the swelling capacity and sorption kinetics of the hydrogel particles to the point where some compositions displayed fast deswelling behavior and the formation of a mechanically stiff outer shell. Ongoing work is now focused on optimizing the chemistry of the polymer hydrogels to tune and control the microstructure of the concrete, with the ultimate goal of designing new concrete mixtures with increased performance and durability.
Biography: Kendra Erk is an Associate Professor of Materials Engineering at Purdue University in West Lafayette, Indiana. Before joining Purdue in 2012, she was a National Research Council Postdoctoral Research Associate in the Polymers Division of the National Institute of Standards and Technology (NIST, Gaithersburg, MD). She received her Ph.D. in 2010 from Northwestern University (Materials Science and Engineering) and her B.S. in Materials Engineering in 2006 from Purdue University. Dr. Erk was the recipient of an NSF CAREER Award in 2015 for her work on hydrogel-based internal curing agents for high-performance concrete. The overall goal of Dr. Erk’s research at Purdue is to develop a better understanding of important structure-property-processing relationships in a wide range of soft materials and complex fluids with engineering relevance, from polymer hydrogels to surfactant-oil-water emulsions. Characterizing the deformation and rheology of the materials is of primary interest, with an emphasis on understanding molecular-level phenomena through experimentation on model systems. @PurdueSoftMSE, http://soft-material-mechanics.squarespace.com/
