Graduate Student Seminar
February 13, 2026
10:00 a.m. ET
CUC McConomy Auditorium
Interfacial Fracture in Soft Polymer Networks: Revisiting Gent's Picture
In recent years, soft polymer networks have enabled advances in wearable electronics, soft robotics, and flexible displays. However, their interfacial fracture behavior remains difficult to predict because it is challenging to disentangle the respective contributions of viscoelastic dissipation and molecular-scale damage to energy dissipation ahead of a crack. In this seminar, I address this challenge using polymer networks labeled with fluorogenic mechanophores. I measure peel behavior over a broad range of crack velocities and temperatures and quantify force-induced molecular damage near the interface using confocal microscopy. These experiments reveal a quantitative connection between viscoelasticity, molecular damage, and adhesion energy that challenges key assumptions embedded in linear viscoelastic fracture theories, building on seminal insights from Alan Gent. More broadly, the results illuminate the molecular and mesoscale mechanisms governing interfacial fracture, refine constitutive frameworks for rate- and temperature-dependent adhesion, and inform the design of polymer networks for increasingly demanding applications
Gabriel Sanoja Lopez
Assistant Professor, Jim and Barbara Miller Endowed Faculty Fellowship in Chemical Engineering
University of Texas, Austin
Prof. Sanoja holds a B.S. in Chemical Engineering from MIT and a Ph.D. from UC Berkeley. Throughout his studies, his research focused on the self-assembly of protein-polymer block copolymers, and the molecular design of polymeric ionic liquids. Prof. Sanoja was then a post-doctoral scholar at ESPCI Paris, where he used polymer mechanochemistry to investigate the role of polymer chain scission on mechanical durability and fracture toughness. With a background in STEM, Prof. Sanoja’s research interest lies at the interface of soft matter and polymer physics, with a focus on using advanced polymerizations and mechanochemistry for engineering the mechanical properties of polymeric materials. Originally from Caracas, Venezuela, he enjoys both intellectual pursuits and everyday pleasure, reflecting his passion for both science and humanity's well-being.
Upcoming Events
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February 20 2026
10:00 AM ET
Materials Science and Engineering
High-Fidelity Atomistic Simulations of Chemistry-Microstructure Interactions in Metals, presented by Rodrigo Freitas, Massachusetts Institute of Technology
CUC McConomy Auditorium
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February 25 2026
2:00 PM ET
Faculty Insights with Mario Berges
Please join us for CMU Engineering's virtual program, “Faculty Insights: A 20 Minute Briefing.” In this series, faculty will share insights into their research, its impact, and provide perspective for the future of the field.
Virtual, link provided to registrants
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February 27 2026
10:00 AM ET
Materials Science and Engineering
presented by Tim Weihs, Johns Hopkins university
CUC McConomy Auditorium
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March 13 2026
10:00 AM ET
Materials Science and Engineering
presented by Rachel Goldman, University of Michigan
CUC McConomy Auditorium
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March 20 2026
10:00 AM ET
Materials Science and Engineering
Accelerating Battery Materials Discovery with AI- and Physics-Powered Molecular Universe Platform, presented by Yumin Zhang, SES AI
CUC McConomy Auditorium
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March 27 2026
10:00 AM ET
Materials Science and Engineering
presented by Daniel Gianola, UC Santa Barbara
CUC McConomy Auditorium