(Macromolecules) Multi-Stimuli Responsive Carbon Nanotube Incorporated Polysiloxane Azobenzene Liquid Crystalline Elastomer Composites
writer:Meng Wang, Sayed Mir Sayed, Ling-Xiang Guo, Bao-Ping Lin, Xue-Qin Zhang, Ying Sun, and Hong Yang*
keywords:LCE
source:期刊
specific source:Macromolecules, 49, 663-671.
Issue time:2016年
In this work, aiming to combine thermal-induced
LC-to-isotropic phase transition effect, azobenzene’s trans-cis tautomerization effect and the photo-thermal effect into
one liquid crystalline elastomer (LCE) system to prepare a
heat/UV/near-infrared(NIR) triple-stimuli-responsive LCE material, we design
and synthesize a polysiloxane-based side-chain side-on azobenzene-containing
LCE matrix embedded with 1 wt% single-walled carbon nanotubes, through
Finkelmann’s two-step crosslinking process coupled with a uniaxial stretching technique.
The multi-stimuli responsive behaviors of this LCE/CNT composite film are
investigated under different external stimuli (heat, UV, NIR). The composite
film can realize a reversible deformation between contraction and extension
under heating/cooling cycles. Moreover, the composite film can
perform an impressive three-dimensional deformation (bending) under UV-light irradiation.
On the contrary, long wavelength light (NIR laser) forces the composite film into
shrinking instead of bending. Most importantly, the shape transformations (three-dimensional
bending vs two-dimensional shrinking) of this novel shape memory material can
be tuned by the light wavelength (UV vs NIR), which might endow this LCE
material with potential applications in control devices and logic gate devices,
etc.