### Mathematics in Engineering

2019, Issue 1: 204-223. doi: 10.3934/Mine.2018.1.204
Research article

# Foldable structures made of hydrogel bilayers

• Received: 05 August 2018 Accepted: 13 November 2018 Published: 20 November 2018
• We discuss self-folding of a thin sheet by using patterned hydrogel bilayers, which act as hinges connecting flat faces. Folding is actuated by heterogeneous swelling due to di erent crosslinking densities of the polymer network in the two layers. Our analysis is based on a dimensionally reduced plate model, obtained by applying a recently developed theory [1], which provides us with an explicit connection between (three-dimensional) material properties and the curvatures induced at the hinges. This connection o ers a recipe for the fabrication and design of the bilayers, by providing the values of the cross-linking density of each layer that need to be imprinted during polymerization in order to produce a desired folded shape upon swelling.

Citation: Virginia Agostiniani, Antonio DeSimone, Alessandro Lucantonio, Danka Lučić. Foldable structures made of hydrogel bilayers[J]. Mathematics in Engineering, 2019, 1(1): 204-223. doi: 10.3934/Mine.2018.1.204

### Related Papers:

• We discuss self-folding of a thin sheet by using patterned hydrogel bilayers, which act as hinges connecting flat faces. Folding is actuated by heterogeneous swelling due to di erent crosslinking densities of the polymer network in the two layers. Our analysis is based on a dimensionally reduced plate model, obtained by applying a recently developed theory [1], which provides us with an explicit connection between (three-dimensional) material properties and the curvatures induced at the hinges. This connection o ers a recipe for the fabrication and design of the bilayers, by providing the values of the cross-linking density of each layer that need to be imprinted during polymerization in order to produce a desired folded shape upon swelling.

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