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arXiv · 1808.07902

How super-tough gels break

Itamar Kolvin·John M. Kolinski·Jian Ping Gong·Jay Fineberg
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Abstract

Fracture of highly stretched materials challenges our view of how things break. We directly visualize rupture of tough double-network (DN) gels at >50\% strain. During fracture, crack tip shapes obey a $x\sim y^{1.6}$ power-law, in contrast to the parabolic profile observed in low-strain cracks. A new length-scale $\ell$ emerges from the power-law; we show that $\ell$ scales directly with the stored elastic energy, and diverges when the crack velocity approaches the shear wave speed. Our results show that DN gels undergo brittle fracture, and provide a testing ground for large-strain fracture mechanics.

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Itamar Kolvin, John M. Kolinski, Jian Ping Gong, Jay Fineberg. 2018-08-23. How super-tough gels break. https://doi.org/10.1103/physrevlett.121.135501

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