A series of azobenzene containing side-on liquid crystalline ABA triblock copolymers were investigated. This triblock series possesses the same central liquid crystal block B and various lengths of the amorphous block...A series of azobenzene containing side-on liquid crystalline ABA triblock copolymers were investigated. This triblock series possesses the same central liquid crystal block B and various lengths of the amorphous block A. Transmission electron microscopy （TEM）, small angle X-rays and neutron scattering （SAXS and SANS） were used to study their morphologies. After annealing the samples over weeks at a temperature within the nematic temperature range of block B, different morphologies （disordered, lamellar, perforated layer and hexagonal cylinder） were observed by TEM. The alignment behavior of these azo triblock copolymers in the magnetic field for artificial muscle application, as well as the phase period and the order-disorder transition （ODT） were studied in situ by SANS.展开更多
Nature is providing inspiration for researchers to mimic its functions or existing structures,which could remarkably promote the development of new materials.Here,a large-size honeycomb-shaped liquid crystal elastomer...Nature is providing inspiration for researchers to mimic its functions or existing structures,which could remarkably promote the development of new materials.Here,a large-size honeycomb-shaped liquid crystal elastomer(LCE)actuator with LC orientation along the height of the honeycomb shape is built by combining magnetic field alignment and soft lithography technology.This homeotropic alignment allowed the height contraction of honeycomb and pore size expansion of hexagons in a reversible manner upon temperature variation.Therefore,this LCE actuator can be used as a structure for temperature-gated separation of particles.Another example is an iris-like LCE actuator,which has the capability of adjusting its aperture size with a temperature variation.Our approach provides a simple way to design customizable sophisticated LCE actuators for various potential applications.展开更多
基金financially supported by the French Embassy in China(Beijing) to Wei Deng(Bourse doctorale en altemance 2004-2007)
文摘A series of azobenzene containing side-on liquid crystalline ABA triblock copolymers were investigated. This triblock series possesses the same central liquid crystal block B and various lengths of the amorphous block A. Transmission electron microscopy （TEM）, small angle X-rays and neutron scattering （SAXS and SANS） were used to study their morphologies. After annealing the samples over weeks at a temperature within the nematic temperature range of block B, different morphologies （disordered, lamellar, perforated layer and hexagonal cylinder） were observed by TEM. The alignment behavior of these azo triblock copolymers in the magnetic field for artificial muscle application, as well as the phase period and the order-disorder transition （ODT） were studied in situ by SANS.
基金This study received support from the French National Research Agency(ANR-16-CE29-0028)from the“Institut Pierre-Gilles de Gennes”(IPGG,laboratoire d’excellence,“Investissements d’avenir”programs ANR-10-IDEX-0001-02 PSL,ANR10-LABX-31 and ANR10-EQPX-34).
文摘Nature is providing inspiration for researchers to mimic its functions or existing structures,which could remarkably promote the development of new materials.Here,a large-size honeycomb-shaped liquid crystal elastomer(LCE)actuator with LC orientation along the height of the honeycomb shape is built by combining magnetic field alignment and soft lithography technology.This homeotropic alignment allowed the height contraction of honeycomb and pore size expansion of hexagons in a reversible manner upon temperature variation.Therefore,this LCE actuator can be used as a structure for temperature-gated separation of particles.Another example is an iris-like LCE actuator,which has the capability of adjusting its aperture size with a temperature variation.Our approach provides a simple way to design customizable sophisticated LCE actuators for various potential applications.
