Speaker Name: Prof. Namrata Gundiah(IISc Bangalore)

Date: 25-03-2026 (Tuesday)

Time: 14:30 PM

Venue: LC102

Abstract: Soft materials generally exhibit large nonlinear deformations, anisotropy, and time-dependent viscoelastic responses. Hydrogels provide a versatile platform to study such behaviors because their mechanical properties can be tuned to mimic biological tissues. However, low toughness and brittle fractures limit their broader use. In this talk, I will present recent work from our laboratory on failures in gelatin hydrogels, with a focus on the role of methylglyoxal crosslinks. To investigate how viscoelasticity influences failure, we develop polyacrylamide hydrogels with similar elastic moduli but distinct viscoelastic properties and probe fracture using cavitation rheology. These experiments reveal striking shape-breaking transitions from spheroidal cavities in viscoelastic gels to ellipsoidal cavities in more elastic hydrogels. Using a modified Rayleigh–Plesset framework, we quantify the role of viscous stresses in hydrogel failure. We further examine how substrate viscoelasticity influences cell adhesion, traction forces, and migration. Finally, to probe the role of fiber reinforcement, we study corneal tissues and introduce methylglyoxal crosslinks to examine how additional crosslinks alter tissue mechanics in keratoconus. Together, these results show how viscoelasticity and microstructure govern cavitation-driven failure in soft materials.