Photoinduced Alignment of Ferroelectric Liquid Crystals Using Azobenzene Polymer Networks of Chiral Polyacrylates and Polymethacrylates

Abstract

Two chiral dimethacrylate and one chiral diacrylate monomer containing an azobenzene group were synthesized and dissolved in a commercial ferroelectric liquid crystal (FLC) host. With two of the monomers, thermally induced radical polymerization with the mixture exposed to linearly polarized irradiation results in a bulk alignment of FLC in the direction perpendicular to the polarization of irradiation light as a result of the photoinduced orientation of azobenzene groups related to the transcis isomerization. The monomer that is most effective for photoalignment of FLC displays a polymer network formed by strings of colloidal particles (∼250 nm in diameter), which exerts a commanding effect on the alignment of FLC as being able to reorient the FLC by changing the polarization direction of subsequent irradiation. The study suggests that the network of colloidal particles is isotropic and that the photoalignment of azobenzene moieties on the large surface of the network dictates the alignment of FLC.

The theoretical interpretation of the Linear/circularly polarized light-induced molecular orientation of the azo group-containing trans-Achiral Schiff base dinuclear complex composite material

“…[31][32][33][34][35][36][37][38][39][40] If only the Coulomb interaction of the chromospheres A between B two can be considered, we assume system dipole interactions between paired the two ones. Now, the Hamiltonian of the system is represented by the equation (3). (3) Where Hamiltonian ( ) or ( ) is of the chromophores A or B, is Coulomb interaction potential between the chromophore A and B.…”

“…Which suggests that all components are contained inside the PMMA films (not surface) . 3 Therefore, we employed polarized electronic spectroscopy to measure aggregation and molecular orientation of the components of hybrid materials. We have investigated polarized electronic spectra of hybrid material of Mn12 and AZ in PMMA cast film after alternate UV and visible light irradiation for 3 min π-π * and n-π * bands suggested increasing of optical anisotropy accompanying with reversible photoisomerizaion of AZ, which may have resulted in previously reported reversible increasing and decreasing of ac magnetic susceptibility.…”

Uji Spektrofotometer Uv-Vis Pada Produk Blending Kristal Cair Kolesteril Akrilat Dengan Kristal Cair Tipe Ester Benzoat

“…Senyawa KCTEB yang berlebih memungkinkan terjadinya serapan maksimum pada panjang gelombang yang lebih tinggi. Hal ini ditunjukkan oleh penelitian yang dilakukan Steve Leclair dkk tahun 2003 [5] No Nama telah tercapai fasa smektik C, karena senyawa tersebut berlebih maka akan terjadi reaksi antara sesama senyawa KCTEB dibantu dengan suhu sehingga memungkinkan untuk terjadinya polimerisasi. Ketika senyawa KCTEB sudah menjadi polimer maka terjadi fenomena dalam polimer, yaitu adanya jarak antara unit kiral dengan rantai utama polimer.…”

Photo-Induced Micellization of Block Copolymers

“…The polymers change their spatial structure in response to stimuli, for example, aggregating [12], aligning [13], bending, [14], and spiraling [15,16]. Molecular self-assembly is also caused by the polymers responding to stimuli, resulting in the construction of high-dimensional structures of the polymers.…”