2025/03/14 by S.M. Walker, Walker, Samuel B., Suzanne M. Fielding +1 · 2 citations
Biochemistry, Genetics and Molecular Biology · Engineering · Materials Science · #Advanced Materials and Mechanics #Calcium Carbonate Crystallization and Inhibition #FOS: Physical sciences #Hydrogels: synthesis, properties, applications #Soft Condensed Matter (cond-mat.soft)
paper · pdf · doi:10.48550/arxiv.2503.11340
openalex publication_date 2025/03/14 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Double network hydrogels show remarkable mechanical performance, combining high strength and fracture toughness with sufficient stiffness to bear load, despite containing only a low density of cross-linked polymer molecules in water. We introduce a simple mesoscale model of a double network material, detailed enough to resolve the salient microphysics of local plastic bond breakage, yet simple enough to address macroscopic cracking. Load sharing between the networks results in a delocalisation of stress such that the double network inherits both the stiffness of its stiff-and-brittle sacrificial network and the ductility of its soft-and-ductile matrix network. The underlying mechanism is a reduction in the Eshelby stress propagator between sacrificial bonds, inhibiting the tendency for the plastic failure of one sacrificial bond to propagate stress to neighbouring sacrificial bonds and cause a follow-on cascade of breakages. The mechanism of brittle macroscopic cracking is thereby suppressed, giving instead ductile deformation via diffusely distributed microcracking.