Optical shutter driven photochemically from anisotropic polymer network containing liquid crystalline and azobenzene molecules

Highly functional macromolecules with a well-defined architecture are the key to designing efficient and smart materials, and these polymeric systems can be tailored for specific applications in a diverse range of fields. Herein, the formation of a new liquid crystalline polymeric network based on the crosslinking of dendrimeric entities by the CuI-catalyzed variant of the Huisgen 1,3-dipolar cycloaddition of azides and alkynes to afford 1,2,3-triazoles is reported. The polymeric material obtained in this way is easy to process and exhibits a variety of properties, which include mesomorphism, viscoelastic behavior, and thermal contraction. The porous microstructure of the polymer network determines its capability to absorb solvent molecules and to encapsulate small molecules, like organic dyes, which can be released easily afterwards. Moreover, all these properties may be easily tuned by modifying the chemical structure of the constituent dendrimers, which makes this system a very interesting one for a number of applications.

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Uv Curable Liquid Crystals and Their Application

MRS Proceedings ◽

10.1557/proc-425-293 ◽

1996 ◽

Vol 425 ◽

Author(s):

H. Takatsu ◽

H. Hasebe

Keyword(s):

Liquid Crystals ◽

Light Scattering ◽

Liquid Crystalline ◽

Room Temperature ◽

Polymer Network ◽

Driving Voltage ◽

Uv Curable ◽

Good Thermal Stability ◽

Photo Polymerization ◽

Smectic A

AbstractSome classes of liquid crystalline monoacrylates having no methylene spacers in a side chain have been prepared. The liquid crystalline monoacrylates have effects to reduce the driving voltage and the hysteresis for a light scattering display of Polymer Network liquid crystals prepared by photo-polymerization-induced phase separation.By photo-polymerization of a chiral monoacrylate monomer in a nematic liquid crystalline host including a black dichroic dye, a polarizer free reflective Spiral Polymer Aligned Nematic (SPAN) Guest Host (GH) LCD exhibiting a low driving voltage has been fabricated. The effect of the spiral polymers made of some kinds of chiral monoacrylates for a Super Twisted Nematic (STN) LCD using SPAN liquid crystals is discussed.UV-curable liquid crystals showing nematic phases at room temperature have been developed. By in situ photo-polymerization, the UV-curable liquid crystals can be utilized for the retardation film with high quality and good thermal stability. The fabrication of various kinds of retardation film using the UV-curable liquid crystals is discussed.UV-curable liquid crystals having isotropic-nematic-smectic A phase sequence have been developed and the photo-polymerization at the state of their uniaxially oriented smectic A phases at room temperature is discussed. The polymerized film is optically uniaxial and transparent without light scattering.

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Coupling of liquid crystalline and polymer network properties in LC-elastomers

Liquid Crystals ◽

10.1080/02678299608032868 ◽

1996 ◽

Vol 21 (4) ◽

pp. 589-596 ◽

Cited By ~ 60

Author(s):

M. Brehmer ◽

R. Zentel ◽

F. Gießbtelmann ◽

R. Germer ◽

P. Zugenmaier

Keyword(s):

Liquid Crystalline ◽

Polymer Network ◽

Network Properties

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Humidity-Responsive Bilayer Actuators Based on a Liquid-Crystalline Polymer Network

ACS Applied Materials & Interfaces ◽

10.1021/am400681z ◽

2013 ◽

Vol 5 (11) ◽

pp. 4945-4950 ◽

Cited By ~ 78

Author(s):

Mian Dai ◽

Olivier T. Picot ◽

Julien M. N. Verjans ◽

Laurens T. de Haan ◽

Albertus P. H. J. Schenning ◽

...

Keyword(s):

Liquid Crystalline Polymer ◽

Liquid Crystalline ◽

Polymer Network ◽

Crystalline Polymer

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Photo Actuation Performance of Nanotube Sheet Incorporated Azobenzene Crosslinked Liquid Crystalline Polymer Nanocomposite

Polymers ◽

10.3390/polym11040735 ◽

2019 ◽

Vol 11 (4) ◽

pp. 735 ◽

Cited By ~ 1

Author(s):

Meng Bi ◽

Yifan He ◽

Yuchang Wang ◽

Wenlong Yang ◽

Ban Qin ◽

...

Keyword(s):

Liquid Crystalline ◽

Microelectromechanical Systems ◽

In Situ Polymerization ◽

Uv Light ◽

Polymer Network ◽

Polymer Nanocomposite ◽

Crystalline Polymer ◽

Light Irradiation ◽

Nanocomposite Films ◽

Biological Engineering

Crosslinked liquid crystalline polymers (CLCPs) containing azobenzene (AZO-CLCPs) are a type of promising material due to their significance in the design of light-driven smart actuators. Developing AZO-CLCP composites by incorporating AZO-CLCPs with other materials is an effective way of enhancing their practicability. Herein, we report an AZO-CLCP/CNT nanocomposite prepared by the in situ polymerization of diacrylates containing azobenzene chromophores on carbon nanotube (CNT) sheets. The liquid crystal phase structure of CLCP matrix was evidenced by the two-dimensional X-ray scattering. The prepared pure AZO-CLCP films and AZO-CLCP/CNT nanocomposite films demonstrated strong reversible photo-triggered deformation under the irradiation of UV light at 366 nm of wavelength, as a result of photo-induced isomerization of azobenzene moieties in the polymer network. But compared to pure AZO-CLCP films, the AZO-CLCP/CNT nanocomposite films could much more rapidly return to their initial shapes after the UV light irradiation was removed due to the elasticity effect of CNT sheets. The deformation behavior of AZO-CLCP/CNT nanocomposite films under the light irradiation was also different from that of the pure AZO-CLCP films due to the interfacial interaction between a polymer network and CNT sheet. Furthermore, incorporation of a CNT sheet remarkably increased the mechanical strength and robustness of the material. We also used this AZO-CLCP/CNT nanocomposite as a microvalve membrane actuator, which can be controlled by light, for a conceptual device of a microfluidic system. The results showed that this AZO-CLCP/CNT nanocomposite may have great potential in smart actuator applications for biological engineering, medical treatment, environment detection and microelectromechanical systems (MEMS), etc.

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