| Autor: |
Sulyanov, Sergey N., Dorovatovskii, Pavel V., Bobrovsky, Alexey Yu., Shibaev, Valery P., Cigl, Martin, Vĕra Hamplová, Bubnov, Alexej, Ostrovskii, Boris I. |
| Rok vydání: |
2018 |
| Předmět: |
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| DOI: |
10.6084/m9.figshare.7212212 |
| Popis: |
The chiral methacrylate monomers with photosensitive azobenzene group possessing the orthogonal smectic A* and tilted smectic C* (Sm-C*) phases have been synthesised and characterised. The monomers have been used as functional side chains for the design of corresponding polymethacrylates. X-ray diffraction has been applied to elucidate the structure and phase behaviour of liquid-crystalline side-chain polymethacrylates with azobenzene-containing central core, chiral fragments and aliphatic spacers and tails of different length. X-ray patterns of polymethacrylates oriented fibres impose the tilted Sm-C* order as a basic structure of these materials. This is complemented by a regular pattern of small-angle diffuse spots, which implies complex positional order on the local scale and serves as a precursor for the formation of a columnar phase. The increase of the total length of the aliphatic tail and spacer of the side-chain fragments leads to formation of the tilted columnar phase (Coltilt*) with two-dimensional monoclinic lattice. For the polymer containing 10 methylene units in both, spacer and aliphatic tail, the Coltilt* precedes the formation of the Sm-C* phase. The observed structural changes are explained as due to coupling between the smectic ordering of the mesogenic side groups and the polymer backbone conformation. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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