- Properties of thermotropic liquid crystalline polyester nanocomposites derived from multi-walled carbon nanotubes
-
A series of nanocomposites containing multi-walled carbon nanotubes (MWNTs) and terephthaloyldi- p-oxybenzoyl chloride-triethylene glycol copolyester (T-T) were prepared by in-situ hightemperature solution polycondensation. The liquid crystalline properties and thermal stability of the resulted MWNTs/T-T nanocomposites were investigated by wide-angle X-ray diffraction (WAXD), polarized optical microscopy (POM), differential scanning calorimetry (DSC), and thermogravimetric analyzer (TGA), respectively. The results showed that MWNT doping at a low concentration improved the thermal stability of T-T matrix and expanded the nematic temperature range without largely changing its conformation, making it more suitable for processing. The dispersion of MWNTs and interfacial interactions between the thermotropic liquid crystalline polymer (TLCP) molecules and the carbon nanotubes (CNTs) were investigated by scanning electron microscopy (SEM) and optical spectroscopies. The UV-vis spectroscopy and fluorescence spectra supported a strong π-π* interaction between the polymer and the nanotube. Copyright
- Zhao, Wen-Feng,Liu, Ji-Xin,Cui, Zhen-Kai,Hu, Wu-Quan,Jiang, Jian,Da, Shi-Jun,Li, Rong
-
-
Read Online
- From cyclohexanone to photosensitive polyesters: Synthetic pathway, basic characterization, and photo-/halochromic properties
-
A bifunctional photosensitive monomer, 2,6-bis-(4-hydroxybenzylidene)cyclohexanone (DHCH) was successfully synthesized by the condensation reaction of cyclohexanone with p-hydroxybenzaldehyde in the presence of hydrochloric acid, as a catalyst. Based on D
- Homocianu, Mihaela,Macsim, Ana Maria,Serbezeanu, Diana,Vlad-Bubulac, Tǎchitǎ
-
-
- Comparative study of phosphorus-containing polymers with high performance properties
-
Polyesters and poly(ester-imide)s have been synthesized by polycondensation reaction of terephthaloyl bis-(4-oxybenzoyl-chloride) with a mixture of 1,12-dodecanediol and various aromatic bisphenol containing phosphorous taken in different ratios. The chem
- Serbezeanu, Diana,Carja, Ionela-Daniela,Vlad-Bubulac, Tachita,Hamciuc, Corneliu,Bruma, Maria
-
p. 393 - 399
(2013/04/24)
-
- Planar-bilayer activities of linear oligoester bolaamphiphiles
-
Voltage-clamp experiments of eight oligoester bolaamphiphiles in two subclasses are described. Syntheses of three new terephthalate-based compounds were achieved in three linear steps. Together with five previously described, related compounds, the ion transport activity was assessed by means of the voltage-clamp technique. All of the compounds show multiple types of conductance behavior in planar bilayers, a subset of which was exponentially voltage-dependent. The varied and irregular activities were summarized with the aid of a recently developed "activity-grid" method.
- Chui, Jonathan K. W.,Fyles, Thomas M.,Luong, Horace
-
p. 1562 - 1569
(2012/01/05)
-
- Synthesis and properties of novel phosphorus-containing thermotropic liquid crystalline copoly(ester imide)s
-
A series of novel phosphorus-containing polyesterimides were prepared from diolsa mixture of a new aromatic phosphorus-containing bisphenol, namely 1,4-bis[N-(4-hydroxyphenyl)phthalimidyl-5-carboxylate]-2-(6-oxido-6H- dibenzoxaphosphorin-6-yl)-n
- Serbezeanu, Diana,Vlad-Bubulac, Tachita,Hamciuc, Corneliu,Aflori, Magdalena
-
experimental part
p. 5391 - 5403
(2011/06/21)
-
- Callimatic and T-shaped liquid crystalline compounds with fluorinated terminal groups
-
A series of liquid crystalline polyesters with a rigid T-shaped or a stick-like mesogenic fragment and fluorinated terminal groups of various structures was synthesized and studied by means of polarization optical microscopy, differential scanning calorim
- Zuev
-
scheme or table
p. 1707 - 1710
(2009/02/06)
-
- Poly(1,3,4-oxadiazole-ester-amide)s
-
New aromatic poly (1,3,4-oxadiazole)s containing both amide and ester groups in the main chain have been synthesized and their properties have been determined and compared with those of wholly aromatic polyamides and poly(1,3,4-oxadiazole)s. These polymers show good thermal stability, with the initial decomposition temperature around 360°C and the glass transition temperature in the range 190°C-270°C. They are easily soluble in certain solvents such as N-methylpyrrolidinone, N,N′-dimethylacetamide and N,N′-dimethylformamide, and can be cast from solutions into thin flexible films.
- Sava, Ion,Iosip, Mariana-Dana,Bruma, Maria
-
p. 515 - 523
(2007/10/03)
-
- Fluorinated poly(benzoxazole-ester)s
-
New poly(benzoxazole-ester)s were prepared by polycondensation of bis(o-aminophenol), such as 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane, with diacid chlorides containing ester groups. The soluble polymer precursor resulting from the first step of polycondensation in N-methylpyrrolidinone (NMP) at low temperature was processed into thin flexible films, which were then thermally treated to reach the fully cyclized structure of poly(benzoxazole-ester)s, as observed by infrared spectra.
- Sava, Ion,Hamciuc, Corneliu,Bruma, Maria,Hamciuc, Elena
-
p. 1161 - 1166
(2007/10/03)
-
- Aromatic polyesters containing heterocyclic units
-
Aromatic poly(phenylquinoxaline-esters) have been synthesized by solution polycondensation of bis(hydroxyphenylquinoxaline)s with two diacid chlorides containing preformed ester units. Also, poly(phenylquinoxaline-esters) containing pendent imide rings have been synthesized by the same procedure using bis(hydroxyphenylquinoxalines) and two diacid chlorides containing preformed imide rings. All these polymers were characterized by infrared spectra, elemental analysis, viscometric measurements and thermogravimetric data.
- Hamciuc, Elena,Hamciuc, Corneliu,Sava, Ion,Belomoina, Natalyia M.,Brumǎ, Maria
-
p. 327 - 333
(2007/10/03)
-
- On the Phase Behaviour of a Liquid-Crystalline Polymer Containing Diaza-18-Crown-6-Ether Units
-
A new synthetic route for a crown ether containing liquid crystalline polymer will be presented.The polymer has been prepared using 1,4,10,13-tetraoxy-7,16-diazacyclooctadecene (diaza-18-crown-6-ether) and terephthaloyl-bis-(4-oxybenzoic) chloride.The mesogenic properties of the polymer have been examined using DSC, polarization microscopy and x-ray diffraction methods. - Keywords: liquid crystals, polymer, crown ether.
- Fischer, H.
-
p. 249 - 254
(2007/10/02)
-
- Fourier transform Raman spectroscopic study of main-chain thermotropic liquid crystalline polyesters
-
The Fourier transform infrared and Raman spectra of the semi-flexible main-chain thermotropic liquid crystal polyester, poly(heptamethylene terephthaloyl-bis-4-oxybenzoate) are presented, and tentative band assignments given.The polymer is investigated as a function of its thermal history, and Fourier transform Raman spectra are recorded with temperature using a high-temperature cell.The results are discussed along with calorimetric and X-ray scattering data.Spectral evidence is presented which is related to both the sample crystallinity, and the crystal-to-liquid crystal phase transition.
- Ellis, G.,Lorente, J.,Marco, C.,Gomez, M. A.,Fatou, J. G.,Hendra, P. J.
-
p. 1353 - 1366
(2007/10/02)
-