Strain-stiffening gels based on latent crosslinking

Yen H. Tran; Matthew J. Rasmuson; Todd S. Emrick; John Klier; Shelly R. Peyton

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arXiv · 1707.09077

Strain-stiffening gels based on latent crosslinking

Yen H. Tran·Matthew J. Rasmuson·Todd S. Emrick·John Klier·Shelly R. Peyton

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Abstract

Gels are an increasingly important class of soft materials with applications ranging from regenerative medicine to commodity materials. A major drawback of gels is their relative mechanical weakness, which worsens further under strain. We report a new class of responsive gels with latent crosslinking moieties that exhibit strain-stiffening behavior. This property results from the lability of disulfides, initially isolated in a protected state, then activated to crosslink on-demand. The active thiol groups are induced to form inter-chain crosslinks when subjected to mechanical compression, resulting in a gel that strengthens under strain. Molecular shielding design elements regulate the strain-sensitivity and spontaneous crosslinking tendencies of the polymer network. These strain-responsive gels represent a rational design of new advanced materials with on-demand stiffening properties with potential applications in elastomers, adhesives, foams, films, and fibers.

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Yen H. Tran, Matthew J. Rasmuson, Todd S. Emrick, John Klier, Shelly R. Peyton. 2017-07-28. Strain-stiffening gels based on latent crosslinking. https://arxiv.org/abs/1707.09077

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