[J. Mater. Chem. C] Mimosa Inspired Bilayer Hydrogel Actuator Functioning in Multi-Environment
writer：Jing Zheng, P Xiao, X Le, W Lu, P. Theato, C Ma, Binyang Du, Jiawei Zhang*, YJ Huang, Tao Chen*
keywords：Mimosa-inspired hydrogel actuator, bilayer composite structure, UCST, LCST
source：期刊
specific source：J. Mater. Chem. C, 2017, Inpress
Issue time：2018年
Hydrogel-based actuators
have attracted significant attention and shown promising applications in many
fields. However, most hydrogel actuators can only act in aqueous media, which
dramatically limits their applications. Hence, the realization of hydrogel
actuators that function under non-aqueous conditions still remains a
significant challenge. Inspired by the water self-circulation mechanism that
contributes to the motion of Mimosa leafs, we herein present a general strategy
towards designing hydrogel actuators that can generate motions in water, oil
and even in open-air environment. A hydrogel with a reverse thermal responsive bilayer
composite Structure was prepared, composed of a hydrogel layer derived from a
polymer featuring a lower critical solution temperature (LCST layer) and a
hydrogel layer derived from a polymer featuring an upper critical solution
temperature (UCST layer). Upon heating, water molecules transferred from the
LCST layer to the UCST layer within the bilayer hydrogel, while under cooling
the reverse process took place, allowing for an actuation even in non-aqueous
environments. This water self-circulation within the bilayer hydrogel enabled a
bending of the hydrogel and hence offers a smart strategy yet with new idea for
actuators working in non-aqueous environments. Such hydrogel actuators may
provide new insights in designing and fabricating of intelligent soft materials
for bio-inspired applications.