am7b13814_si_001.pdf (2.27 MB)
Download fileElectrical Control of Shape in Voxelated Liquid Crystalline Polymer Nanocomposites
journal contribution
posted on 2017-12-14, 00:00 authored by Tyler Guin, Benjamin A. Kowalski, Rahul Rao, Anesia D. Auguste, Christopher A. Grabowski, Pamela F. Lloyd, Vincent P. Tondiglia, Benji Maruyama, Richard A. Vaia, Timothy J. WhiteLiquid
crystal elastomers (LCEs) exhibit anisotropic mechanical, thermal,
and optical properties. The director orientation within an LCE can
be spatially localized into voxels [three-dimensional (3-D) volume
elements] via photoalignment surfaces. Here, we prepare nanocomposites
in which both the orientation of the LCE and single-walled carbon
nanotube (SWNT) are locally and arbitrarily oriented in discrete voxels.
The addition of SWNTs increases the stiffness of the LCE in the orientation
direction, yielding a material with a 5:1 directional modulus contrast.
The inclusion of SWNT modifies the thermomechanical response and,
most notably, is shown to enable distinctive electromechanical deformation
of the nanocomposite. Specifically, the incorporation of SWNTs sensitizes
the LCE to a dc field, enabling uniaxial electrostriction along the
orientation direction. We demonstrate that localized orientation of
the LCE and SWNT allows complex 3-D shape transformations to be electrically
triggered. Initial experiments indicate that the SWNT–polymer
interfaces play a crucial role in enabling the electrostriction reported
herein.