Synthesis and Properties of Liquid-Crystalline Semi-Rigid Polyesters Based on Isophthalates of Nitro- or Methoxyazobenzene and Dioxydiundecanols of Biphenyl or 2,5-Diphenyl-1,3,4-Thiadiazole

Sato, Moriyuki; Mizoi, Miyuki; Uemoto, Yuko

doi:10.1002/1521-3935(20011201)202:18<3634::aid-macp3634>3.0.co;2-j

Cited by 16 publications

(12 citation statements)

References 12 publications

(23 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Polymer syntheses Polyesters 3a-f and 7a,b having one or two side chain azobenzene moieties in the polymer repeat unit, except for the previously reported polyester 3a [20], were preprared from the diethyl isophthalates 1b-f with one azobenzene unit or terephthalate derivative 6 bearing two methoxyazobenzene units by melt or high temperature solution polycondensation with a dioxydiundecanol of DPTD 2a or a dioxydihexanol of biphenyl 2b. The terephthalate monomer 6 was prepared from diethyl 2,4-dihydroxyterephthalate 4 and monobromo compound 5 of methoxyazobenzene by the Williamson reaction in 61% yield; this showed an enantiotropic nematic phase in the range 102.3-120.0 ‡C (schlieren texture) as given in § 2.4, and an X-ray pattern of a sample quenched from the LC state showed a broad reflection at around 2h~22 ‡.…”

Section: Resultsmentioning

confidence: 99%

“…31, NO. 9, SEPTEMBER 2004, 1219-1226 combined-type polyesters [20,21]. It is of interest to establish how the presence of one or two azobenzene units attached by the aliphatic chains in the side chain will affect the LC properties of combined-type polyesters containing the main chain calamitic mesogens.…”

Section: Introductionmentioning

confidence: 95%

“…In previous work we investigated the relationships between polymer structures and the LC and optical properties in combined-type homo-and copolyisophthalates having electron-withdrawing nitro and/or electron-donating methoxyazobenzene moieties in the side chain, and calamitic mesogens such as biphenyl units in the main chain [20,21]. The homoand copolymers showed smectic (B, C or E) phases, although specific interactions such as electron donoracceptor interactions played no role in the formation or stabilization of the smectic phases.…”

Section: Introductionmentioning

confidence: 99%

“…Characterization FTIR and 1 H NMR spectra were recorded as described previously [20][21][22][23][24][25][26][27][28][29]. DSC measurements, optical texture observations, X-ray diffraction (XRD) and molecular weight measurements by size exclusion chromatography (SEC) were carried out according to previously published procedures [20][21][22][23][24][25][26][27][28][29] …”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Liquid crystalline homopolyesters having main chain calamitic mesogens and one or two side chain azobenzene moieties in the repeat units

Mizoi

Yano

2004

Liquid Crystals

Self Cite

View full text Add to dashboard Cite

Combined semi-rigid homopolyesters, containing both main chain calamitic mesogens and one or two side chain azobenzene units separated by aliphatic (hexamethylene, octamethylene and decamethylene) chains in the polymer repeat units, were prepared and their liquid crystalline properties characterized. Polyesters having two side chain azobenzene units and a main chain biphenyl moiety showed a higher ordered smectic B or smectic F phase, whereas the other polymers containing a main chain 2,5-diphenyl-1,3,4-thiadiazole unit and one or two side chain methoxyazobenzene units formed a smectic C phase despite the presence of different mesogens in the main and side chains. This is probably due to the compact molecular chain-packing and intra-and intermolecular interactions between the polymer backbones and the two azobenzene units.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 95%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Liquid crystalline homopolyesters having main chain calamitic mesogens and one or two side chain azobenzene moieties in the repeat units

Mizoi

Yano

2004

Liquid Crystals

Self Cite

View full text Add to dashboard Cite

show abstract

“…Five-membered, hetero-aromatic compounds containing imine(-CH=N-) groups, such as thiadiazole have long been of interest as luminophores for optical application due to their electron accepting nature [1][2][3][4][5][6][7][8]. The thiadiazoles have been broadly applied in the areas of pharmaceutical, agricultural, industrial and polymer chemistry.…”

Section: Introductionmentioning

confidence: 99%

Synthesis, characterization, surface morphology properties and effects of annealing temperature on optical properties of poly(2-(((5-phenyl-1,3,4-thiadiazole-2-yl)imino)methyl)phenyl methacrylate) (PTMPMA)

2014

View full text Add to dashboard Cite

In this study, a new 5-phenyl-1,3,4-thiadiazole-containing vinyl monomer and its polymer were synthesized. The characterizations of the ligand, monomer and polymer were carried out using FTIR, UV-Vis, 1 H-NMR, elemental analysis and gel permeation chromatography techniques. The roughness average, root-mean-square roughness, surface skewness and surface kurtosis parameters of the poly(PTMPMA) film were found to be 1.98 nm, 2.84 nm, 1.529 and 5.777, respectively. Effects of the annealing temperature on optical properties of the poly(2-(((5-phenyl-1,3,4-thiadiazole-2-yl)imino)methyl)phenyl methacrylate) (PTMPMA) were investigated. The important optical parameters such as refractive index, optical band gap, angle of incidence, imaginary part of optical conductivity and real part of dielectric constants of the poly(PTMPMA) decrease and other important optical parameters such as excitation and dispersion energy, angle of refraction, real part of optical conductivity and imaginary part of dielectric constants of the poly(PTMPMA) increase with increasing annealing temperature. The absorption band edge values of the polymer films were found to be 2.34, 1.85 and 1.74 eV for 298, 523 and 643 K, respectively. The optical band gap values of the polymer films were found to be 3.314, 2.943 and 2.917 eV for 298, 523 and 643 K, respectively. The poly(PTMPMA) can be used as an active polymer layer in production of the electronic devices such as polymer diodes and metal-semiconductor contacts.Electronic supplementary material The online version of this article (

show abstract

Thermotropic liquid‐crystalline polymers containing five‐membered heterocyclic groups. X. Relationships between structures of semirigid polyesters based on three disubstituted 2,5‐diphenyl‐1,3,4‐thiadiazoles and thermotropic liquid‐crystalline and optical properties

Sato

Nakashima

Uemoto

2003

J. Polym. Sci. A Polym. Chem.

Self Cite

View full text Add to dashboard Cite

Thermotropic liquid-crystalline (LC) semirigid polyesters based on three terphenyl analogues of 1,3,4-thiadiazole (2,5-diphenyl-1,3,4-thiadiazole)s (DPTD) linking undecamethyleneoxy chain at different substituted positions were synthesized from three disubstituted (4,4Ј-, 3,4Ј-, and 3,3Ј-) dioxydiundecanols of DPTD and four diesters, and the relationships between polymer structures and LC and optical properties were investigated. DSC measurements, texture observations, and wide-angle X-ray analyses revealed that the polymers composed of DPTD moiety having a more linear molecular structure and 1,4-phenylene unit or short aliphatic chain tend to exhibit LC smectic C and/or A phases. The following observations were made: (1) the emergence of smectic C and/or A phases in all the polymers on the basis of 4,4Ј-disubstituted DPTD, (2) formation of enantiotropic smectic C and/or A phases in the polymers containing a 1,4-phenylene unit in the main chain, (3) formation of a more stable smectic C phase in the polymers having a short aliphatic [(CH 2 ) 4 ] chain, and (4) a decrease of the mesomorphic property of the polyesters in the order of 4,4Ј-DPTD Ͼ 3,4Ј-DPTD Ͼ 3,3Ј-DPTD. Solution and solid-state ultraviolet-visible and photoluminescent spectra indicated that all the polyesters display maximum absorbances and blue emissions arising from the DPTD moiety, whose peak maxima were shifted to lower wavelengths in the order of 4,4Ј-DPTD Ͼ 3,4Ј-DPTD Ͼ 3,3Ј-DPTD as well as the aforementioned LC property.

show abstract

Synthesis and Properties of Liquid-Crystalline Semi-Rigid Polyesters Based on Isophthalates of Nitro- or Methoxyazobenzene and Dioxydiundecanols of Biphenyl or 2,5-Diphenyl-1,3,4-Thiadiazole

Cited by 16 publications

References 12 publications

Liquid crystalline homopolyesters having main chain calamitic mesogens and one or two side chain azobenzene moieties in the repeat units

Liquid crystalline homopolyesters having main chain calamitic mesogens and one or two side chain azobenzene moieties in the repeat units

Synthesis, characterization, surface morphology properties and effects of annealing temperature on optical properties of poly(2-(((5-phenyl-1,3,4-thiadiazole-2-yl)imino)methyl)phenyl methacrylate) (PTMPMA)

Thermotropic liquid‐crystalline polymers containing five‐membered heterocyclic groups. X. Relationships between structures of semirigid polyesters based on three disubstituted 2,5‐diphenyl‐1,3,4‐thiadiazoles and thermotropic liquid‐crystalline and optical properties

Contact Info

Product

Resources

About