22289-04-9Relevant academic research and scientific papers
Mesomorphic behaviour of N-benzoyl-N′-aryl thioureas liquid crystalline compounds
Ili, Monica,Bucos, Madalina,Dumitracu, Florea,C?rcu, Viorel
, p. 1 - 6 (2011)
A series of N-benzoyl-N′-aryl thiourea derivatives bearing alkoxy groups in terminal positions have been prepared and investigated for their potential liquid crystals properties. It was found that only the compounds which have only two alkoxy chains show calamitic mesomorphic behaviour, with nematic, smectic A and C phases being displayed. The type and stability of these mesophases are greatly influenced by the alkyl chain length. Successive introduction of additional alkoxy groups on the benzoyl moiety led to a significant decrease of the clearing points and suppression of the mesogenic character. Using of branched alkyl chain, 2-ethyl-hexyl, instead of normal alkyl group, led to the disappearance of mesogenic behaviour together with the lowering of the clearing temperature. The influence of chain length and number of chains is discussed.
Bent-core compounds with two branched chains: Evidence of a new dark conglomerate mesophase
Ocak, Hale,Bilgin-Eran, Belkiz,Prehm, Marko,Tschierske, Carsten
, p. 4590 - 4597 (2013/07/26)
Biphenyl-3,4′-diol derived bent-core compounds with branched side chains have been synthesized and characterized to study the influence of terminal branched groups on mesophase properties and transition temperatures of bent-core mesogens. The liquid crystalline properties of the compounds were investigated by differential scanning calorimetry, optical polarizing microscopy and X-ray scattering. Depending on the length of the chain, the size of molecular branches and the position of branched chains, either enantiotropic or monotropic rectangular columnar phases were observed. For one of the compounds combining two different branched side chains, a new type of optically isotropic dark conglomerate phase (MIso[*]) was found. It is proposed to be a distorted version of a non-tilted or only slightly tilted B6-like intercalated smectic phase with additional in plane order.
Esters of anhydrosugar alcohols as plasticizers
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, (2008/06/13)
The invention consists of esters of anhydrosugar alcohols useful as plasticizers for polymeric compounds. Specifically, esters are formed of bis-anhydrohexitols, such as isosorbide, isomannide and isosiditide, and used as substitutes for the phthalate-bas
