Shape-Changing CNT-Polymer Composites

1 Light-driven Shape-changing CNT-Polymer Composites 

As mentioned earlier/ Ahir et al. have studied the photomechanical behavior of three types of MWNT-elastomer nanocomposites irradiated with near-IR light under isostrain conditions, including PDMS, styrene-isoprene-styrene (SIS), and a nematic LCE with a polysiloxane backbone. 

They have shown that these composite materials have the novel ability to change their actuation direction upon IR irradiation. 

CNT-polymer composites at very low nanotube loadings exhibit substantial electrostrictive strains when exposed to an electric field that is dramatically lower than that required by neat polymers. Zhang et al. have shown that the crystallinity. Young s modulus, dielectric constant, electrostrictive strain, and elastic energy density of electrostrictive poly(vinylidene fluoride-trifluor-oethylene-chlorofluoroethylene) P(VDF-TrFE-CFE)] can be simultaneously improved by inclusion of only 0.5 wt% of MWNTs. At an applied electric field of 54 MV m the 0.5 wt% nanocomposite generates a strain of 2%, which nearly doubles that of pure P(VDF-TrFE-CFE) polymer. 

Electrical field-driven pure nematic LCE actuators have not been developed because the characteristic rotation energy density is too low compared with the 

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