scholarly journals Novel soluble aromatic poly(amideimide)s containing 9,9-diphenylfluorene moieties: characterization and optical properties

2006 ◽  
Vol 4 (4) ◽  
pp. 604-619 ◽  
Author(s):  
Ewa Schab-Balcerzak ◽  
Eugenia Grabiec ◽  
Bożena Jarząbek ◽  
Łukasz Grobelny ◽  
Małgorzata Kurcok ◽  
...  
Keyword(s):  
Main Chain ◽  
Molecular Structures ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Free Standing ◽  
Aromatic Diamines ◽  
Polar Solvents ◽  
X Ray ◽  
Transparent Films ◽  
Optical Behavior

AbstractA series of aromatic poly(amideimide)s containing 9,9-diphenylfluorene moieties and the amide units in the main chain have been synthesized by solution polycondensation reaction of newly prepared diamidedianhydride with several aromatic diamines: 1,3-phenylenediamine, 3,3′-dimethoxy-biphenyl-4,4′-diamine, 4,4′-oxydianiline, 4,4′-(1,3-phenylenedioxy)dianiline, 4,4′-(9-fluorenylidene)dianiline and 1,5-diaminonaphthalene. Molecular structures of the polymers obtained have been characterized using 13C NMR, 1H NMR and FTIR spectroscopies. The polymers prepared are readily soluble in aprotic polar solvents, and form optically transparent films by solution casting. The resultant poly(amideimide)s have been analyzed by differential scanning calorimetry (DSC), thermogravimetry (TG) and wide-angle X-ray diffraction measurements. They exhibited high levels of thermal stability, with decomposition temperatures in the range 452–494 °C, and high glass transition temperatures (181–278 °C). The optical behavior of these polymers has been investigated in NMP solution as well as in the films. The photoluminescence (PL) spectra of the free-standing films prepared from the poly(amideimide)s exhibited maximum emission bands around 506–525 nm in the green region.

Liquid crystalline polyureas with oligo(ethylene glycol) sequences

e-Polymers ◽  
2010 ◽  
Vol 10 (1) ◽  
Author(s):  
Shahram Mehdipour-Ataei ◽  
Leila Akbarian-Feizi
Keyword(s):  
Liquid Crystalline ◽  
Spectroscopic Method ◽  
Polymerization Reaction ◽  
X Ray Diffraction ◽  
Subsequent Reaction ◽  
Scanning Calorimetry ◽  
Polar Solvents ◽  
X Ray ◽  
H Nmr ◽  
Ft Ir

AbstractA diamine monomer containing ester, amide and ether functional groups was prepared and its polymerization reaction with different diisocyanates to give main chain poly(ester amide ether urea)s was investigated. The monomer was synthesized via reaction of terephthaloyl chloride with 4-hydroxybenzoic acid and subsequent reaction of the resulted diacid with 1,8-diamino-3,6-dioxaoctane. The polymers were characterized by FT-IR and 1H-NMR spectroscopic method and elemental analysis. The resulting polymers exhibited excellent solubility in polar solvents. Crystallinity of the resulted polymers was evaluated by wide-angle X-ray diffraction (WXRD) method, and they exhibited semi-crystalline patterns. The glass transition temperatures (Tg) of the polymers determined by differential scanning calorimetry (DSC) and dynamic mechanical thermal analysis (DMTA) were in the range of 88-112 °C. The temperatures for 10% weight loss (T10) from their thermogravimetric analysis (TGA) curves were found to be in the range of 297-312 °C in air. Also the prepared polyureas showed liquid crystalline character.

Chiral Liquid Crystalline Polymers Containing Isosorbide Groups

2013 ◽  
Vol 781-784 ◽  
pp. 403-406
Author(s):  
Mei Tian ◽  
Zhi Xin Xu ◽  
Li Gao ◽  
Dan Shu Yao ◽  
Xiao Zhi He ◽  
...  
Keyword(s):  
Liquid Crystal ◽  
Liquid Crystalline ◽  
Main Chain ◽  
Liquid Crystalline Polymers ◽  
Optical Microscope ◽  
Liquid Crystal Polymers ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Crystalline Polymers

A series of new main-chain liquid-crystal polymers (LCPs) were prepared from sebacoyl chloride (SD) and various amount of 4, 4-Dihydroxy-2, 2-dimethyl Benzalazine (DDBA) and isosorbide (ISO). The liquid crystal (LC) properties were investigated by polarized optical microscope (POM), differential scanning calorimetry (DSC) and X-ray diffraction measurements. P1 exhibited a typical nematic thread texture, which contains no ISO. P2-P7 are Sc* and N LCPs, which exhibited broken fan-shaped texture and droplet texture. The introduction of chiral units into the polymers led to a change of mesomorphase, as compared with P1.

Synthesis, structure, and magnetic properties of diphenylphosphinates of cobalt(II) and manganese(II). The crystal and molecular structures of the γ forms of poly-bis(μ-diphenylphosphinato)cobalt(II) and manganese(II)

1991 ◽  
Vol 69 (2) ◽  
pp. 277-285 ◽  
Author(s):  
Jing-Long Du ◽  
Steven J. Rettig ◽  
Robert C. Thompson ◽  
James Trotter
Keyword(s):  
Magnetic Properties ◽  
Heavy Atom ◽  
Molecular Structures ◽  
Antiferromagnetic Coupling ◽  
Monoclinic Space Group ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Lattice Constants ◽  
Linear Chains

The synthesis of the β and γ forms of M(Ph2PO2)2 where M = Co and Mn are described and the compounds are characterized by infrared spectroscopy, differential scanning calorimetry, X-ray powder diffraction, and low-temperature (2–80 K) magnetic susceptibility studies. Single crystal X-ray diffraction studies are reported on the γ forms. Crystals of the γ forms of poly-bis(μ-diphenylphosphinato)cobalt(II) and poly-bis(μ-diphenylphosphinato)manganese(II) are isomorphous, crystallizing with 4 formula units per unit-cell in the monoclinic space group P21/c. Lattice constants are a = 8.080(2), 8.161(1), b = 23.550(6), 23.751(1), c = 11.726(3), 11.6946(6) Ǻ, and β = 92.88(2), 93.026(8)° for the Co and Mn derivatives respectively. The structures were solved by heavy atom methods and were refined by full-matrix least-squares procedures to R = 0.039 and 0.045 for 4041 and 2878 reflections with I ≥ 3σ(I), respectively. Both crystal structures consist of double phosphinate-bridged chain polymers containing tetrahedrally coordinated metal atoms: Co—O = 1.950(2)–1.963(2) Ǻ, O—Co—O = 104.81(8)–117.77(9)°, Mn—O = 2.016(3)–2.033(3) Ǻ, O—Mn—O = 103.2(1)–114.7(1)°. All four compounds exhibit antiferromagnetic coupling and magnetic susceptibilities have been analyzed according to two Heisenberg models for linear chains of metal ions with S = 3/2 for cobalt and S = 5/2 for manganese. The Weng model (with values for the Wagner and Friedberg model in parentheses) gives –J = 0.25 (0.26) cm−1 and 0.55 (0.60) cm−1 for the β and γ forms, respectively, of Co(Ph2PO2)2, and 0.34 (0.36) cm−1 and 0.17 (0.17) cm−1 for the β and γ forms, respectively, of Mn(Ph2PO2)2. Key words: crystal structure, diphenylphosphinates of cobalt(II) and manganese(II), magnetic properties.

Structures of Energetic Acetylene Derivatives HC≡CCH2ONO2, (NO2)3CCH2C≡CCH2C(NO2)3 and Trinitroethane, (NO2)3CCH3

2013 ◽  
Vol 68 (5-6) ◽  
pp. 719-731 ◽  
Author(s):  
Thomas M. Klapötke ◽  
Burkhard Krumm ◽  
Richard Moll ◽  
Alexander Penger ◽  
Stefan M. Sproll ◽  
...  
Keyword(s):  
Electron Diffraction ◽  
Gas Phase ◽  
Quantum Chemical ◽  
Room Temperature ◽  
Molecular Structures ◽  
X Ray Diffraction ◽  
Polar Solvents ◽  
X Ray ◽  
Nmr Study ◽  
Acetylene Derivatives

The molecular structures and relative ratios of the two conformers (anti and gauche) of HCCCH2ONO2 detected in the gas phase at room temperature have been determined by electron diffraction. The results are discussed on the basis of quantum chemical calculations. The molecular structures of (NO2)3CCH2C≡CCH2C(NO2)3 and (NO2)3CCH3 have been determined by X-ray diffraction. A109Ag NMR study was performed for silver trinitromethanide Ag[C(NO2)3] in various polar solvents.

New thermally stable poly(amide-imide)/montmorillonite reinforced nanocomposite based on N,N′-pyrromellitoyl-bis-l-valine: synthesis and characterization

2014 ◽  
Vol 21 (1) ◽  
pp. 1-6 ◽  
Author(s):  
Khalil Faghihi ◽  
Narges Dehnavi ◽  
Mohsen Hajibeygi
Keyword(s):  
Main Chain ◽  
Diphenyl Ether ◽  
Nanocomposite Films ◽  
X Ray Diffraction ◽  
Visible Spectroscopy ◽  
Scanning Calorimetry ◽  
Solution Intercalation ◽  
X Ray ◽  
Polymeric Chains ◽  
Uv Visible

AbstractTwo new samples of poly(amide-imide) (PAI)/nanocomposites reinforced montmorillonite containing N,N′-pyrromelitoyl-bis-l-valine moiety in the main chain were synthesized by a solution intercalation technique. PAI 3 as a source of polymer matrix was synthesized by the direct polycondensation reaction of N,N′-pyrromelitoyl-bis-l-valine 1 with 4,4′-diamino diphenyl ether 2 in the presence of triphenyl phosphite, CaCl2, pyridine and N-methyl-2-pyrrolidone. The morphology and structure of the resulting PAI-nanocomposite films 4a and 4b with 5% and 10% silicate particles were characterized by Fourier transform infrared spectroscopy, X-ray diffraction and scanning electron microscopy. The effect of clay dispersion and the interaction between clay and polymeric chains on the properties of nanocomposites films were investigated by using UV-visible spectroscopy, thermogravimetric analysis and differential scanning calorimetry.

Synthesis and Characterization of Highly Soluble and Heat Stable New Poly(amide-ether)s Containing Pyridine Rings in the Main Chain

e-Polymers ◽  
2008 ◽  
Vol 8 (1) ◽  
Author(s):  
Ahmad Banihashemi ◽  
Mohammad Reza Vakili
Keyword(s):  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Ether Linkage ◽  
Aromatic Diamines ◽  
X Ray ◽  
H Nmr ◽  
Good Solubility ◽  
Heat Stable ◽  
Diacid Chloride

AbstractA pyridine-based diacid containing ether linkage was synthesized via reaction of 2,6-dichloropyridine with 3-hydroxybenzoic acid in presence of potassium hydroxide in dimethyl sulfoxide (DMSO). The corresponding diacid chloride was synthesized by reaction of the diacid with oxalyl chloride. New poly (amide-ether)s were prepared by solution polycondensation reaction of the prepared diacid chloride with different commercial aromatic diamines. The synthesized polymers were characterized by elemental analysis, IR, and 1H NMR spectra, wide-angle X-ray diffraction, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC); inherent viscosity and solubility were studied. These polymers showed high thermal stability and good solubility.

Studies on the Preparation, Characterization and Solubility of -Cyclodextrin-Roxythromycin Inclusion Complexes

2009 ◽  
Vol 2 (2) ◽  
pp. 523-530
Author(s):  
D. Nagasamy Venkatesh ◽  
S. Karthick ◽  
M. Umesh ◽  
G. Vivek ◽  
R.M. Valliappan ◽  
...  
Keyword(s):  
Dissolution Rate ◽  
Inclusion Complexes ◽  
Phase Solubility ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Ir Studies ◽  
Poorly Soluble ◽  
Poorly Soluble Drug

Roxythromycin/ β-cyclodextrin (Roxy/ β-CD) dispersions were prepared with a view to study the influence of β-CD on the solubility and dissolution rate of this poorly soluble drug. Phase-solubility profile indicated that the solubility of roxythromycin was significantly increased in the presence of β-cyclodextrin and was classified as AL-type, indicating the 1:1 stoichiometric inclusion complexes. Physical characterization of the prepared systems was carried out by differential scanning calorimetry (DSC), X-ray diffraction studies (XRD) and IR studies. Solid state characterization of the drug β-CD binary system using XRD, FTIR and DSC revealed distinct loss of drug crystallinity in the formulation, ostensibly accounting for enhancement of dissolution rate.

Crystal structure determination of the conformation of two bicyclo[3.3.1]nonan-ones

1985 ◽  
Vol 63 (6) ◽  
pp. 1166-1169 ◽  
Author(s):  
John F. Richardson ◽  
Ted S. Sorensen
Keyword(s):  
Crystal Structure ◽  
Direct Methods ◽  
Chair Conformation ◽  
Molecular Structures ◽  
Boat Conformation ◽  
X Ray Diffraction ◽  
Space Group ◽  
X Ray ◽  
Final Agreement

The molecular structures of exo-7-methylbicyclo[3.3.1]nonan-3-one, 3, and the endo-7-methyl isomer, 4, have been determined using X-ray-diffraction techniques. Compound 3 crystallizes in the space group [Formula: see text] with a = 15.115(1), c = 7.677(2) Å, and Z = 8 while 4 crystallizes in the space group P21 with a = 6.446(1), b = 7.831(1), c = 8.414(2) Å, β = 94.42(2)°, and Z = 2. The structures were solved by direct methods and refined to final agreement factors of R = 0.041 and R = 0.034 for 3 and 4 respectively. Compound 3 exists in a chair–chair conformation and there is no significant flattening of the chair rings. However, in 4, the non-ketone ring is forced into a boat conformation. These results are significant in interpreting what conformations may be present in the related sp2-hybridized carbocations.

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