TY  - JOUR
A1  - Ryabchun, Alexander
A1  - Raguzin, Ivan
A1  - Stumpe, Joachim
A1  - Shibaev, Valery
A1  - Bobrovsky, Alexey
T1  - Cholesteric Polymer Scaffolds Filled with Azobenzene-Containing Nematic Mixture with Phototunable Optical Properties
JF  - Scientific reports
N2  - The past two decades witnessed tremendous progress in the field of creation of different types of responsive materials. Cholesteric polymer networks present a very promising class of smart materials due to the combination of the unique optical properties of cholesteric mesophase and high mechanical properties of polymer networks. In the present work we demonstrate the possibility of fast and reversible photocontrol of the optical properties of cholesteric polymer networks. Several cholesteric photopolymerizable mixtures are prepared, and porous cholesteric network films with different helix pitches are produced by polymerization of these mixtures. An effective and simple method of the introduction of photochromic azobenzene-containing nematic mixture capable of isothermal photoinducing the nematic isotropic phase transition into the porous polymer matrix is developed, It is found that cross-linking density and degree of polymer network filling with a photochromic nematic mixture strongly influence the photo-optical behavior of the obtained composite films. In particular, the densely cross-linked films are characterized by a decrease in selective light reflection bandwidth, whereas weakly cross-linked systems display two processes: the shift of selective light reflection peak and decrease of its width. It is noteworthy that the obtained cholesteric materials are shown to be very promising for the variety applications in optoelectronics and photonics.
KW  - liquid crystalline polymer
KW  - azobenzene
KW  - cholesteric phase
KW  - phototunable optical properties
KW  - selective light reflection
KW  - LC composites
Y1  - 2016
U6  - https://doi.org/10.1021/acsami.6b09642
SN  - 1944-8244
VL  - 8
SP  - 27227
EP  - 27235
PB  - American Chemical Society
CY  - Washington
ER  -