Tailoring Poisson's Ratio via the Directed Self-Assembly of Liquid Crystal Elastomers

Auxetic materials are of great interest due to their superior toughness, resilience and shear resistance compare to positive Poisson’s ratio materials. Auxetic materials are negative Poisson’s ratio materials that expand in the transverse direction when a tensile force is applied. Currently, most auxetic materials are porous or foam based materials. However, creating a non-porous auxetic material will lead to high density and effective stiffness materials with improved impact resistance and vibration damping. Here, we utilized ink-jet printing to prepare designer elastomers with distinct local elastic properties by controlling the alignment of the liquid crystal mesogens. Programming the local orientation and elastic properties of liquid crystal elastomers leads to the ability to tune the Poisson’s ratio in a non-porous elastomeric film. Both computational and experimental results will be shown.