105299-45-4Relevant academic research and scientific papers
The photochemical behavior of polyhydroxy styrene with azofragments containing free methacrylic double bounds
Nadtoka, Oksana,Vretik, Lyudmyla,Gavrylko, Tetiana,Syromyatnikov, Volodymyr
, p. 115 - 123 (2017)
Polymer material which combines advantages of photoaligning azo-compounds with thermal stability of the induced anisotropy provided by free methacryloyl groups was synthesised. FTIR spectroscopy was employed for clarification its photochemical behavior. T
Photocontrolled manipulation of a microscale object: A rotational or translational mechanism
Kausar, Abu,Nagano, Hiroto,Kuwahara, Yutaka,Ogata, Tomonari,Kurihara, Seiji
, p. 508 - 515 (2011)
In this paper the photocontrolled manipulation of solid materials on the surface of a liquid crystalline thin film is described. Three different types of films namely cholesteric liquid crystal (ChLC), compensated nematic liquid crystal (NLC) and nematic LC were used. The rotational and translational manipulation of the microscale solid object was induced by irradiation of light and mode of manipulation (either translational or rotational) was changed by changing the isomer of the azobenzene compound used to make the film. Rotational motion of the object was observed on the ChLC and compensated NLC films containing chirally pure azobenzene compound. The direction of rotational motion was controlled either by changing the optical isomer of the chiral azobenzene or by changing the irradiating light (from ultraviolet to visible). When racemic mixture of the chiral azobenzene compound was used, a translational motion of the object was observed. Even though the direction of the translational motion can be controlled by controlling irradiation position, more facile and precise manipulation of the objects was possible by spatially controlled irradiation of Ar+ laser and diode UV laser.
Multiresponsive hydrogels based on xylan-type hemicelluloses and photoisomerized azobenzene copolymer as drug delivery carrier
Cao, Xuefei,Peng, Xinwen,Zhong, Linxin,Sun, Runcang
, p. 10000 - 10007 (2014)
Stimulus-responsive hydrogels, which can undergo significant physicochemical changes in response to various physical or chemical stimuli, have drawn wide attention in many fields. In this study, novel photoresponsive hydrogels prepared by free radical cop
Photoresponsive side-chain liquid crystalline polymers with amide group-substituted azobenzene mesogens: Effects of hydrogen bonding, flexible spacers, and terminal tails
Li, Xinjuan,Fang, Liangjing,Hou, Leigang,Zhu, Lirong,Zhang, Ying,Zhang, Baolong,Zhang, Huiqi
, p. 5532 - 5542 (2012)
The synthesis of a series of new photoresponsive side-chain liquid crystalline polymethacrylates with amide group-substituted azobenzene (azo) mesogens and different length of flexible spacers and terminal tails via conventional free radical polymerization is described. The resulting azo polymers proved to have high thermal stability and good solubility in common organic solvents (e.g., tetrahydrofuran and chloroform). Differential scanning calorimetry, polarizing optical microscopy, and small angle X-ray scattering studies confirmed the presence of obvious enantiotropic smectic C liquid crystalline phases (with a bilayer lamellar structure) for all these polymers. The introduction of an amide group into the azo mesogen led to the formation of strong hydrogen bonding among the side chains of the polymers (as revealed by variable temperature FT-IR), which played a decisive role in forming and stabilizing the liquid crystalline mesophases of the polymers. In addition, the length of the flexible spacers and terminal tails also significantly influenced their phase transition behaviors. Furthermore, the photoresponsivity of the polymer solutions was verified and the effects of the molecular structures of the polymers on their photoresponsive properties were also studied.
A Twist-Bend Nematic (NTB) Phase of Chiral Materials
Gorecka, Ewa,Vaupoti, Nataa,Zep, Anna,Pociecha, Damian,Yoshioka, Jun,Yamamoto, Jun,Takezoe, Hideo
, p. 10155 - 10159 (2015)
New chiral dimers consisting of a rod-like and cholesterol mesogenic units are reported to form a chiral twist-bend nematic phase (NTB) with heliconical structure. The compressibility of the NTB phase made of bent dimers was found to be as large as in smectic phases, which is consistent with the nanoperiodic structure of the NTB phase. The atomic force microscopy observations in chiral bent dimers revealed a periodicity of about 50 nm, which is significantly larger than the one reported previously for non-chiral compounds (ca. 10 nm).
Synthesis of reactive azobenzene main-chain liquid crystalline polymers via michael addition polymerization and photomechanical effects of their supramolecular hydrogen-bonded fibers
Fang, Liangjing,Zhang, Hongtao,Li, Zidong,Zhang, Ying,Zhang, Yuying,Zhang, Huiqi
, p. 7650 - 7660 (2013)
A new and efficient strategy for obtaining a series of reactive azobenzene (azo)-containing main-chain liquid crystalline polymers (LCPs) is described, which involves the first design and synthesis of acrylate-type azo monomers with different length of flexible spacers and an amino end-group (in its trifluoroacetate salt form) and their subsequent Michael addition polymerization under mild reaction conditions. The resulting polymers showed rather high thermal stability, relatively low glass transition temperatures, a broad temperature range of smectic C liquid crystalline phase, and reversible photoresponsive behavior. The presence of secondary amino groups in the backbones of these azo main-chain LCPs not only made them highly reactive precursors for various new functional linear and cross-linked azo LCPs but also led to the formation of hydrogen-bonding interactions among their polymer chains. Supramolecular hydrogen-bonding cross-linked LCP fibers were directly fabricated by using the simple melt spinning method, which proved to have a high order of mesogen along the fiber axis and exhibit good mechanical properties, fast and reversible photoinduced bending and unbending behaviors, and large photoinduced stress (240 kPa) at close to ambient temperature as well as excellent photodeformation fatigue resistance.
Hydrogen-bonded supercoil self-assembly from achiral molecular components with light-driven supramolecular chirality
Wang, Yangyang,Zhou, Deyan,Li, Haining,Li, Ruiru,Zhong, Yueyao,Sun, Xuan,Sun, Xun
, p. 6402 - 6409 (2014)
Supercoils self-assembled from two achiral molecular components have been synthesized in order to better understand the structure and functionality of this chiral supramolecular association. The two-component synthon is a complementary hydrogen-bond pair having one melamine core and three photoaddressable azobenzene units, which self-assembled into long and helical fibers with intrinsic conformational chirality. Hierarchical self-assembly was presented where one-dimensional helixes bundled into a higher order optically active supercoil structure, leading to spontaneous chiral symmetry breaking and amplification of chirality. Circular dichroism (CD) spectroscopy, transmission electron microscopy (TEM) and atomic force microscopy (AFM), as well as X-ray diffraction (XRD) techniques reveal the chiral nature of the assembly. Accordingly, a plausible mechanism of a hierarchical self-assembly process has been proposed, which presents a valid approach for constructing supramolecular chirality from achiral molecular building blocks through non-covalent interactions. The morphology and chirality of the supercoils demonstrate photoresponsivity, which is induced from the photoisomerization of the azobenzene components within the self-assembled nanostructures. Furthermore, the supercoil is a highly proton-conductive material because of its highly ordered structure and the proton transfer between the H-bonded melamine and azobenzene units within this two-component association.
Modified clays as efficient acid-base catalyst systems for diazotization and diazocoupling reactions
Bahulayan, Damodaran,John, Litka,Lalithambika, Malathy
, p. 863 - 869 (2003)
Diazotization and diazocoupling reactions of aniline and its substituted derivatives with phenol and other aromatic amines over ecofriendly clay catalysts is described. This inexpensive, non-corrosive and reusable catalysts were found to exhibit bifunctional catalytic properties for these reactions. No considerable decrease in the efficiency of the catalysts were observed after five cycles of operation. The new method totally avoids the use of acids and alkalies.
Photocontrolled translational motion of a microscale solid object on azobenzene-doped liquid-crystalline films
Kausar, Abu,Nagano, Hiroto,Ogata, Tomonari,Nonaka, Takamasa,Kurihara, Seiji
, p. 2144 - 2147 (2009)
(Figure Presented). On the move: Irradiation of azobenzene-doped liquid crystalline films with UV/Vis light results in the photocontrolled translational motion of microscale solid object on the surface, which occurs through cis-trans isomerization of the
A reactive azobenzene liquid-crystalline block copolymer as a promising material for practical application of light-driven soft actuators
Lv, Jiu-An,Wang, Wei,Wu, Wei,Yu, Yanlei
, p. 6621 - 6626 (2015)
Cross-linked liquid-crystalline polymers containing azobenzene have been drawing great research interest of scientists due to their significant values in the design of light-driven soft actuators. However, poor processabilities due to the chemical cross-l
