55379-96-9Relevant academic research and scientific papers
New photoreactive polymers containing short side chains as orientation layer materials: effect of side chain lengths on the alignment of liquid-crystals
Ree,Lee,Kim
, p. 503 - 508 (2001)
A series of photoreactive polymers having cinnamoyl moieties with various flexible chain lengths as side groups were newly synthesized. The polymers were soluble in common organic solvents, producing a good quality of thin films in spin- and bar-coating and subsequent baking process. Their photoreactivity to UV light and photoalignment behavior were determined. And the polymers were evaluated as an orientation layer material to control the alignment of liquid-crystals on the film surface.
“Effect of the linking unit on the calamitic-shaped liquid crystal: a comparative study of two homologous series of benzoate and cinnamate linked compounds”
Kashyap, Dinesh,Patel, Sunil,Prajapat, Varsha,Sharma, Vinay,Vasava, Dilip
, p. 58 - 70 (2019/08/28)
Two homologous series based on three linking groups have been synthesized and well characterized by elemental analyses and spectroscopic techniques such as Fourier transform infrared [FT-IR] and proton magnetic resonance magnetic resonance [1H NMR] spectroscopy. The mesomorphic properties of these compounds were observed by using optical polarized microscopy (POM) and confirmed by differential scanning calorimetry (DSC) analysis. In this present investigation, we have synthesized two homologous series viz. (E)-4-(3-(4-(tetra decanoyloxy) phenyl) acryloyl) phenyl-4-n-alkoxy benzoate (Series-1) and 4-((E)-3-(4-(((E)-3-(4-n-alkoxy phenyl) acryloyl) oxy) phenyl)-3-oxo prop-1-en-1-yl) phenyl tetradecanoate (Series-2). Both of the series are differing with respect to the first linking group. All the homologous in following series displays LC properties on heating as well as cooling condition except first four homologous (C1 to C4) in series-1 and six homologous (C1 to C6) in series-2. To get more insights, the HOMO, LUMO studies are carried out which supports intramolecular charge transfer interactions in this class of mesogens.
Bowl-shaped fluorescent liquid crystals derived from 4-: Tert butyl calix[4]arene and trans cinnamic acid derivatives
Sharma, Vinay S.,Singh, Hemant Kumar,Sharma, Anuj S.,Shah, Akshara P.,Shah, Priyanka A.
, p. 15575 - 15584 (2019/10/19)
A new family of bowl-shaped molecules with a calix[4]arene rigid core appended by four-side and two-side substitution with trans 4-n-alkoxy cinnamic acid has been synthesized and well characterized. The LC behaviours of the novel materials were studied by using optical polarising microscopy, differential scanning calorimetry and high-temperature powder X-ray diffraction methods to confirm the smectic organization. It is found that all of the prepared materials display enantiotropic LC phases in the present series-1 (1d4-1, 1d5-l, 1d8-1, 1d10-l, 1d12-l, 1d14-l) and series-2 (1d4-1l, 1d5-ll, 1d8-1l, 1d10-ll, 1d12-ll, 1d14-ll). The electrochemical behaviour shows the higher reactivity of the proposed derivatives, which is in good agreement with the DFT values. The relationship between the structure and the mesomorphic behaviour of the compounds in both series is discussed. These synthesized supramolecular compounds show blue luminescence in solution as well as in solid thin films under long wavelength UV light. To get more insights, HOMO and LUMO studies were carried out, which support intramolecular charge transfer interactions in this class of mesogens.
Mesomorphism dependence on central bridge and tail ended polar group
Ranchchh, Avani R.,Chavda, Kavita,Bhanderi, Roshani,Patel, Suman,Bhoya
, p. 33 - 42 (2019/02/24)
A novel azoester homologous series of laterally and terminally substituted viz, RO–C6H4–CH=CH–COO–C6H3–(CH3) –N=N–C6H4–Cl is synthesized, characterized and studied with a view to understand and establish the relation between molecular structure and thermotropic liquid crystalline property of its homologs. Series consists of twelve homologs. LC properties commence from very first member of a series and continue up to last homolog as enantiotropic nematic with absence of smectic property even in the monotropic condition. Transition temperatures of homologs were determined by polarizing optical microscopy equipped with a heating stage. The transition curves Cr?N and N?I behaved in normal manner. Thermal stability for nematic is 196.7?C whose mesophaselength ranges from 35°C to 131°C.
Mesomorphism dependence on molecular rigidity and flexibility
Ranchchh, Avani R.,Bhoya
, p. 43 - 51 (2019/02/24)
A novel homologous series of liquid crystalline properties is synthesized and studied with a view to understand the effect of molecular structure on its thermotropic properties. Novel homologous series consisted of thirteen homologs. All the homologs are enantiotropically smectogenic with absence of nematic property even in the monotropic condition. Textures of the homologs as observed through an optical hot stage polarizing microscopy. The mesophase temperature range vary minimum from 6.0°C to a maximum 37.0°C at the methyloxy and propyloxy derivatives of a series respectively with its thermal stability (Sm–I) 127.0°C. Transition curves of a phase diagram behaved in normal manner. Odd–even effect is observed for Sm–I transition curve.
“Dependence of Mesomorphism in Combination with Fluoro and Chloro Groups”
Ranchchh, Avani R.,Tharesha, Bhavna R.,Bhoya
, p. 49 - 58 (2019/07/03)
A novel azoester homologous series with chloro lateral group and a fluoro terminal end group was synthesized and characterized for mesomorphic properties. It consists of thirteen azo ester derivatives from trans-4-n-alkoxy cinnamic acid with 4-hydroxy-3-chloro phenyl azo-3-chloro-4-fluoro benzene. Mesomorphic property commences from C4homologue as smectic.C1 to C3 member of the series are non-mesomorphic. C4 to C18 homologous are enantiotropic smectic A phase. The nematic mesophase is totally absent. Texture and transition temperatures of the homologues are determined by an optical polarizing microscopy equipped with heating stage. 1H NMR, IR spectra, mass spectra, of some member is included. The spectroscopic analysis supports the molecular structure. A phase diagram is used to illustrate the mesomorphic behaviour across the series. Mesophaselength for smectic is varying from18.0°C to 69.00C. Mesomorphic properties of the novel azoester series are compared with structurally similar series.
Synthesis and Mesogenic Properties of Liquid Crystals Based on Cholesterol and Cinnamic Acid Derivatives
Zong, Xuenan,Wu, Changcheng
, p. 60 - 73 (2019/03/05)
A group of new mesomorphic compounds with cholesterol-based, which have derivative of the cinnamic acid, with different lengths of terminal alkoxy chains, are synthesized and characterized. The mesomorphic properties were investigated by DSC and POM. All target compounds showed a cholesteric phase. For 12-TC and 14-TC besides a cholesteric phase, also revealed a SmA* phase. The experimental results demonstrated that with the increase in the terminal chain lengths, the thermal stability of the smectic mesophases of these liquid crystals was increased, and these compounds shows brilliant color changes in the temperature ranges of cholesteric phase.
The effect of position of octadecyloxy tail on the formation of liquid crystal with chalconyl-ester and chalconyl-vinyl ester series: Comparison with corresponding linkage group
Solanki,Sharma, Vinay. S.,Patel
, p. 216 - 232 (2017/03/08)
Two series of chalconyl-based liquid crystals which differ from each other in the position of the first linking group have been synthesized and characterized by elemental analyses and spectroscopic techniques such as Fourier transform infrared and proton magnetic resonance magnetic resonance [1H NMR] spectroscopy. The mesomorphic properties of these compounds were observed by optical polarized light microscopy (POM) and differential scanning calorimetry (DSC). We have synthesized two homologous series viz. 3-(3-(4-(Octadecyloxy) phenyl) acrylonyl) phenyl 3-(4-n-alkoxyphenyl) acrylate (series-1) and 3-(3-(4-(Octadecyloxy) phenyl) acryloyl) phenyl 4-n-alkoxy benzoate (series-2). Series-1 has chalconyl-ester central linkage group while in series-2 chalconyl-vinyl ester group is present and tail octadecyloxy side chain is common in both homologous series. All the homologous in present series display LC property in enantiotropical manner except first three homologous in both series.
Mesogenic naphthyl derivatives
Patel,Prajapati
, p. 106 - 115 (2017/03/08)
Two new mesogenic homologous series of liquid crystalline naphthalene derivatives with different central linkages: 2- Naphthyl-4-n-alkoxybenzoates (I) and trans-2-Naphthyl -4-n –alkoxycinnamates(II), have been synthesized and characterized by a combination of elemental analysis and standard spectroscopic methods. Twelve compounds have been synthesized in both the series I and II. In series I, methoxy to n-pentyloxy derivatives are non mesogenic, n-hexyloxy to n-hexadecyloxy derivatives exhibit monotropic nematic mesophase. Smectic A mesophase commences from n-decyloxy derivatives as a monotropy and persist up to the last member synthesized. All the 12 compounds of series II exhibit mesomorphism. Methoxy to n-propyloxy derivatives exhibit monotropic nematic mesophse, and n-butyloxy to n-tetradecyloxy derivatives exhibit enantiotropic nematic mesophase. n-Hexayloxy to n-hexadecyloxy derivatives also exhibit enantiotropic smectic A mesophase. The mesomorphic properties of present series were compared with each other and with a structurally related mesogenic homologous series to evaluate the effects of central linkage on mesomorphism.
Molecular flexibility dependence on mesogenic behaviors of isomeric and nonisomeric series
Rakhasia,Ranchchh, Avani R.,Bhoya
, p. 159 - 167 (2017/03/08)
A novel homologous series containing vinyl ester and azomethane central bridges and n-alkoxy as well as 3″,4″-dimethyl groups as flexible terminal/lateral groups viz. RO?C6H4?CH = CH?COO?C6H4?N?CH?C6H3-(CH3)2 have been synthesized and studied with a view to establishing the relation between molecular structure and thermotropic liquid crystal (LC) properties with reference to molecular flexibility within the series. The series consists of twelve homologues (C1 to C16). C6 and C7 homologues are smectogenic plus nematogenic and C8 to C16 homologues are only smectogenic, and the rest of the homologues (C1 to C5) are nonmesomorphic. Transition temperatures and the textures of the homologues were determined using an optical polarizing microscope equipped with a heating stage (POM). The textures of a nematic phase are threaded or Schlieren and that of a smectic phase are of the A or C type. Analytical, thermal and spectral data support the molecular structures. Smectic and nematic thermal stabilities are 116.85°C and 147.5°C, respectively. Whose Sm?N/I and N-I mesophase lengths are varied between 15°C to 21°C and 25°C to 62°C, respectively. The novel compounds are compared with structurally-similar series.
