Mesophase Studies and Charge Transportation Properties of 3,6-dicarbethoxy-2,7,10,11-tetra-pentyloxytriphenylene

2011 ◽  
Vol 181-182 ◽  
pp. 193-196
Author(s):  
Chun Xiu Zhang ◽  
Jia Ling Pu ◽  
Hao Wu ◽  
Ao Zhang ◽  
Ming Xia Zhang ◽  
...  
Keyword(s):  
Differential Scanning Calorimetry ◽  
Liquid Crystal ◽  
Optical Microscopy ◽  
Chemical Structure ◽  
Room Temperature ◽  
Time Of Flight ◽  
Scanning Calorimetry ◽  
Columnar Phase ◽  
Discotic Liquid Crystal ◽  
Time Of Flight Method

In this study, a triphenylene-based discotic liquid crystal 3,6-dicarbethoxy-2,7,10,11-tetra-pentyloxytriphenylene was synthesized. The chemical structure was characterized by FTIR, 1HNMR.The mesophases of the material synthesized here was characterized by using polarizing optical microscopy (POM), differential scanning calorimetry (DSC). It was found that the compound displayed columnar phase during cooling at 164.7 °C and the columnar phase can be preserved even at room temperature. The charge transportation properties of the compound were measured by using time-of-flight method.

Synthesis and Phase Behavior of a New Thiophene Monomer as Nematic Liquid Crystal

2014 ◽  
Vol 989-994 ◽  
pp. 185-188
Author(s):  
Lin Wang ◽  
Yu Jiao Xie ◽  
Xing Xing Zhang ◽  
Jian She Hu
Keyword(s):  
Differential Scanning Calorimetry ◽  
Liquid Crystal ◽  
Phase Behavior ◽  
Optical Microscopy ◽  
Nematic Liquid Crystal ◽  
Chemical Structure ◽  
Scanning Calorimetry ◽  
H Nmr ◽  
Heating And Cooling ◽  
Ft Ir

The synthesis of a new liquid crystal thiophene monomer of (E)-4-(6-(3-(thiophen-3-yl)- acryloyloxy) hexyloxy) biphenyl-4’-ethylbenzoate (LC-M) is presented. The chemical structure of this monomer and intermediate compounds was characterized by FT-IR and1H-NMR. The phase behavior was investigated by polarizing optical microscopy and differential scanning calorimetry. LC-M showed nematic threaded and schlieren textures on heating and cooling cycles.

Dependence of Phase Transition of a Bent-Core Liquid Crystal on the Heating Rate

2010 ◽  
Vol 663-665 ◽  
pp. 787-790 ◽  
Author(s):  
Qing Lan Ma ◽  
Yuan Ming Huang
Keyword(s):  
Phase Transition ◽  
Differential Scanning Calorimetry ◽  
Liquid Crystal ◽  
Optical Microscopy ◽  
Heating Rate ◽  
Broad Peak ◽  
Crystal Phase ◽  
Scanning Calorimetry ◽  
Polarized Optical Microscopy ◽  
Crystal Compound

A bent-core liquid crystal compound N,N-bis (4-propoxybenzylidene)benzene- 1,3-diamine was synthesized. Phase transition properties of the synthesized compound with the deferent heating rate were characterized with differential scanning calorimetry and polarized optical microscopy. , respectively. Our results demonstrated that the bent-core compound exhibited the completely undivided multi-phases in heating-rate ranges from 1oC/min to 6oC/min while it showed a broad-peak crystal phase in higher heating-rate ranges of 7-10oC/min for the first heating.

Evidence for room temperature mesomorphism in a mixed-valent diruthenium(II,III) quintapalmitoleate polymer

1998 ◽  
Vol 76 (11) ◽  
pp. 1520-1523
Author(s):  
Jennifer F Caplan ◽  
Christopher A Murphy ◽  
Susan Swansburg ◽  
Robert P Lemieux ◽  
T Stanley Cameron ◽  
...  
Keyword(s):  
Differential Scanning Calorimetry ◽  
Liquid Crystal ◽  
Powder Diffraction ◽  
Strong Evidence ◽  
Room Temperature ◽  
Variable Temperature ◽  
Mixed Valence ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Crystal Transition

The synthesis of Ru2(μ-O2CR)4(μ´-O2CR) (1), R = -CH2(CH2)6CH=CH(CH2)5CH3, has been achieved and characterization using elemental analysis and FTIR and UV-Vis spectroscopies undertaken. Strong evidence for a hexagonal discotic mesophase has been found using differential scanning calorimetry, variable-temperature polarizing optical microscopy, and X-ray powder diffraction. A solid to liquid crystal transition was found upon heating at 128°C and the mesophase is found to persist to room temperature upon cooling from 150°C. This is the first report of room temperature mesomorphism in a mixed-valent metallomesogen. Key words: ruthenium carboxylate, liquid crystal, metallomesogen, mixed valence, polymer.

Synthesis and Mesomorphic Properties of a Series of Cholesteric Liquid Crystals

2010 ◽  
Vol 663-665 ◽  
pp. 759-762 ◽  
Author(s):  
Qing Lan Ma ◽  
Yuan Ming Huang
Keyword(s):  
Phase Transition ◽  
Differential Scanning Calorimetry ◽  
Liquid Crystal ◽  
Liquid Crystals ◽  
Optical Microscopy ◽  
Scanning Calorimetry ◽  
Polarized Optical Microscopy ◽  
Phase Transition Temperatures ◽  
Second Category ◽  
Mesomorphic Properties

A series of cholesterol liquid crystal compounds was synthesized. Phase-transition temperatures and mesomorphic textures of these synthesized compounds were characterized with differential scanning calorimetry and polarized optical microscopy, respectively. In these molecules the terminal ester chains CnH2n-1COO-, where n was the number of carbon atoms in the terminal ester chains, were linked to the cholesterol core. All of the synthesized cholesterol compounds exhibited mesophases for the first heating. However, as temperature decreased from their clearing points, their micrographs can also be divided into two categories, the first category exhibits branch-like mesophase textures for n in the range of 1-10 while the second category exhibits branch-like crystal textures for n in the range of 11-18.

Synthesis and Mesomorphism of Rigid Bridge Triphenylene Discotic Liquid Crystal Dimers

2010 ◽  
Vol 428-429 ◽  
pp. 41-45
Author(s):  
Hui Zhou ◽  
Wen Hao Yu ◽  
Bi Qin Wang ◽  
Ping Hu ◽  
Ke Qing Zhao
Keyword(s):  
Liquid Crystal ◽  
Room Temperature ◽  
Alkyl Chain ◽  
Scanning Calorimetry ◽  
Polarized Optical Microscopy ◽  
Discotic Liquid Crystal ◽  
Rigid Spacer ◽  
Temperature Liquid ◽  
Columnar Mesophases ◽  
Homocoupling Reaction

Pd-Cu catalyzed homocoupling reaction has been used for the synthesis of symmetrical triphenylene discotic liquid crystal dimers, [C18H6(OCnH2n+1)5(O2CC6H4C≡C-)]2 (n = 4, 5, 6, 7, 8, 9), which connected two triphenylene discogens via a long rigid spacer. The purity and structure of monomers and dimers have been characterized with 1H NMR, IR and high resolution Mass. Their fine thermal stability has been confirmed by the results of thermogravimetry analysis (TGA). Polarized optical microscopy (POM) and differential scanning calorimetry (DSC) results have shown that the monomers and dimers exhibit columnar mesophases (Col). The dimers display wide mesophase ranges and are room temperature liquid crystals, and their clearing points increased with the lengthening of peripheral alkyl chain.

Influence of Cooling Rates on Phase Transitions of Bent-Core Liquid Crystal 1,3-Phenylene-bis[4-(hexylcarboyloxyl)benzylideneamine]

2010 ◽  
Vol 428-429 ◽  
pp. 247-250 ◽  
Author(s):  
Yuan Ming Huang ◽  
Qing Lan Ma ◽  
Bao Gai Zhai
Keyword(s):  
Differential Scanning Calorimetry ◽  
Phase Transitions ◽  
Liquid Crystal ◽  
Optical Microscopy ◽  
Cooling Rate ◽  
Scanning Calorimetry ◽  
Slow Cooling ◽  
Cooling Rates ◽  
Polarized Optical Microscopy ◽  
Fast Cooling

The influence of cooling rate on the phase transitions of a three-benzene-ring containing bent-core liquid crystal 1,3-phenylene-bis[4-(hexylcarboyloxyl)benzylideneamine] has been investigated by means of differential scanning calorimetry and polarized optical microscopy. Our results show that the cooling rates in the second cooling run pose significant effects on the phase transitions of the bent-core liquid crystal despite the cooling rates in the first cooling run pose little effects on the phase transitions. In the second cooling run, the banana phases survived only when the cooling rates were in the range of 14~15oC/min whereas both slow cooling rates which were less than 13oC/min and fast cooling rates which were higher than 16oC/min made the banana phases disappeared.

Deep-Blue Photoluminescent Properties of a Liquid Crystal TB10A

2011 ◽  
Vol 181-182 ◽  
pp. 33-38 ◽  
Author(s):  
Qing Lan Ma ◽  
Rui Xiong ◽  
Yuan Ming Huang
Keyword(s):  
Differential Scanning Calorimetry ◽  
Liquid Crystal ◽  
Electronic Structures ◽  
Room Temperature ◽  
Tight Binding ◽  
Electronic Structure Calculations ◽  
Scanning Calorimetry ◽  
Deep Blue ◽  
Tight Binding Method ◽  
Structure Calculations

A typical liquid crystal (LC) N,N-(terephthalylidene) bis (4-decylbenzenamine) (TB10A) was firstly synthesized at room temperature. The synthesized LC TB10A were investigated by differential scanning calorimetry (DSC), polarizing optical microscopy (POM), ultraviolet-visible (UV-vis) spectrophotometry, photoluminecence (PL) spectroscopy and electronic structure calculations. Upon the 325 nm excitation, the dilute tetrahydrofuran solutions of TB10A could give off blue PL. With Hückel tight-binding method, the electronic structures of the TB10A were calculated. Our results demonstrated that the deep-blue PL observed at about 489 nm (2.54 eV) can be assigned to theπ* →ntransition for the TB10A.

scholarly journals 2-{3,5-Bis-[5-(3,4-didodecyloxyphenyl)thien-2-yl]phenyl}-5-(3,4-didodecyloxyphenyl)thiophene

Molbank ◽  
10.3390/m1225 ◽  
2021 ◽  
Vol 2021 (2) ◽  
pp. M1225
Author(s):  
Matthias Jochem ◽  
Heiner Detert
Keyword(s):  
Liquid Crystal ◽  
Optical Microscopy ◽  
Boronic Acid ◽  
Suzuki Coupling ◽  
Scanning Calorimetry ◽  
Polarized Optical Microscopy ◽  
The Core ◽  
Discotic Liquid Crystal ◽  
Acid Catalyzed

Star-shaped compounds are widely recognized as emerging materials for optical and electrical applications and as scaffolds of discotic liquid crystal. While the C3-symmetrical tri(phenylthienyl)benzene is the core for several electroopotical materials, no liquid crystal with this scaffold has yet been reported. Acid-catalyzed cyclocondensation of bromoacetylthiophene gives a C3-symmetrical star, threefold Suzuki coupling results in extension of the conjugated system. With 3,4-didodecylocyphenyl boronic acid, a star with a large rigid conjugated system and flexible aliphatic periphery is obtained. Differentials scanning calorimetry and polarized optical microscopy reveal an enantiotropic mesophase from 66 °C to 106 °C.

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