Programmable Liquid Crystal Elastomers Prepared by
Thiol–Ene Photopolymerization
Taylor
H. Ware
Zachary
P. Perry
Claire M. Middleton
Scott
T. Iacono
Timothy J. White
10.1021/acsmacrolett.5b00511.s002
https://acs.figshare.com/articles/journal_contribution/Programmable_Liquid_Crystal_Elastomers_Prepared_by_Thiol_Ene_Photopolymerization/2132038
The
spontaneous conversion of a flat film into a 3-D shape requires
local programming of the mechanical response. Historically, the ability
to locally program the mechanical response of high strain (>30%)
liquid
crystalline elastomers (LCEs) has been limited to magnetic or mechanical
alignment techniques, which limits spatial resolution. Recently, we
reported on the preparation of LCEs capable of 55% strain with spatial
control of the mechanical response at scales as small as 0.01 mm<sup>2</sup>. Here, we report a distinct formulation strategy to realize
programmable stimulus-response in LCEs. Photopolymerization of thiol–ene/acrylate
formulations yields materials that exhibit large reversible strain
up to 150%. The photopolymerization reaction is extremely rapid, reducing
preparation time from days to minutes. The mechanical behavior of
these materials can be tuned by varying cross-link density. Spatial
and hierarchical programming of the director profile is demonstrated,
enabling 3-D shape change, including twisting ribbons and localized
Gaussian curvature.
2015-09-15 00:00:00
alignment techniques
strain
photopolymerization reaction
formulation strategy
Gaussian curvature
director profile
material
0.01 mm 2.
response
programming
LCE
preparation time
Programmable Liquid Crystal Elastomers