Model Compound Studies of Rigid Rod Aromatic Heterocyclic Polymer Systems, the X-Ray Crystal Structure of 2,6-Diphenylbenzo (1,2-d; 5,4-d') Diimidazole Tetrahydrate, C2OH14N4. 4H2O, a Model System for the Study of Polymer-Water Interaction in Polybenzimidazoles.

1983 ◽  
Author(s):  
M. Hunsaker ◽  
W. W. Adams ◽  
A. V. Fratini
Keyword(s):  
Crystal Structure ◽  
Model Compound ◽  
Model System ◽  
Polymer Systems ◽  
X Ray ◽  
Water Interaction ◽  
Rigid Rod ◽  
Aromatic Heterocyclic ◽  
Heterocyclic Polymer

Thermal Stability Of Rigid-rod Polymers

1988 ◽  
Vol 134 ◽  
Author(s):  
Lisa R. Denny ◽  
Ivan J. Goldfarb ◽  
Edward J. Soloski
Keyword(s):  
Thermal Stability ◽  
Chemical Structure ◽  
Processing Conditions ◽  
Thermal Gravimetric ◽  
Polymer Systems ◽  
Environmental Resistance ◽  
Factors Influencing ◽  
Rigid Rod ◽  
Aromatic Heterocyclic ◽  
Thermal Stability Of

ABSTRACTOne of the primary factors influencing the research and development of rigid-rod polymers in the Materials Laboratory has been the excellent environmental resistance of this class of aromatic heterocyclic benzobisazole polymers. Thermal stability of these materials has been determined utilizing thermal analytical, Isothermal Aging and combined Thermal Gravimetric-Mass Spectrometry (TG-MS) techniques. Correlations between the thermal stability and chemical structure, varying substituent groups and processing conditions for these polymers have been observed. An overview of the thermal stability of these rigid-rod polymer systems is presented.

The role of hydrogen bonding in rigid-rod polymers: the crystal structure of a polybenzobisimidazole model compound

Polymer ◽  
2000 ◽  
Vol 41 (25) ◽  
pp. 9003-9010 ◽  
Author(s):  
D.W. Tomlin ◽  
A.V. Fratini ◽  
M. Hunsaker ◽  
W. Wade Adams
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bonding ◽  
Model Compound ◽  
Rigid Rod

Zur Struktur und Komplexchemie von Phosphinoderivaten des 5-Methoxy-2(5H)-furanons / Structure and Coordination Chemistry of Phosphino Derivatives of 5-Methoxy-2(5H)-furanon

1980 ◽  
Vol 35 (9) ◽  
pp. 1075-1082 ◽  
Author(s):  
D. Fenske ◽  
H. Prokscha ◽  
P. Stock ◽  
H. J. Becher
Keyword(s):  
Crystal Structure ◽  
Coordination Chemistry ◽  
Structure Analysis ◽  
Model Compound ◽  
Crystal Structure Analysis ◽  
X Ray ◽  
Derivatives Of ◽  
Cl Atoms ◽  
Cl Atom ◽  
Similar Complex

With R2PSi(CH3)3 (R = C6H5, i-C3H7, t-C4H9) one Cl atom of 3,4-dichlor-5-methoxy-2(5 H)-furanon (1) is substituted by the R2P group. An x-ray crystal structure analysis of the phosphino derivative with R = C6H5 (2) it has shown that of the two Cl atoms in 1 only the β-position (to C= O) is substituted. The coordination chemistry of 2 and its bis- (diphenylphosphino) derivative (3) is studied by preparation of the compounds 2 · Mo(CO)5 and 3 · Mo(CO)4. With PdCl2 · 2 C6H5CN (2) gives a dinuclear complex [2 · PdCl2]2, with bridging Cl atoms. The structure is established by a comparison with the similar complex of PdCl2 and 2-chloro-diphenylphosphino-maleic acid dimethylestor, which was synthe­sized as a model compound and studied by x-ray crystal structure analysis.

Effect of chain ends on the structure of aramid oligomers

2008 ◽  
Vol 86 (1) ◽  
pp. 7-19 ◽  
Author(s):  
Hakim Mehenni ◽  
Hélène Guillou ◽  
Christian Tessier ◽  
Josée Brisson
Keyword(s):  
Crystal Structure ◽  
Crystal Structures ◽  
Model Compound ◽  
Dimethyl Formamide ◽  
X Ray Diffraction ◽  
Aromatic Rings ◽  
X Ray ◽  
Internal Distribution ◽  
Diffraction Patterns ◽  
Additional Form

Synthesis, X-ray diffraction, and Fourier transform infrared spectroscopy of aliphatic–aromatic aramid oligomers are reported with the aim of shedding light on the effect of end-chain substituent on the morphology and structure of poly(para-phenylene terephthalamide) or PPTA. Three types of X-ray powder diffraction patterns were observed: one similar to that of PPTA form I, one similar to that of PPTA form II, and an additional form never reported. Some compounds, differing by their internal distribution of amide–aromatic rings, adopt two different crystal structures, whereas compounds having the same internal amide–aromatic arrangements, but differing by the nature of the end-groups, can adopt the same crystal structure. This clearly shows that both factors influence the packing adopted by the chains. Single-crystal structures of two polymorphs of a nitro-terminated model compound were resolved; both forms incorporate dimethyl formamide, and both show completely different packing. Infrared amide I and II band positions of most studied compounds match those observed for PPTA forms I or II, indicating that they exhibit planar hydrogen bonded sheets of molecules.Key words: aramid, crystal structure, poly(para-phenylene terephtalamide).

Pseudo-ladder rigid-rod polymers: dihydroxy pendent benzothiazole aromatic heterocyclic polymer and copolymers

Polymer ◽  
1994 ◽  
Vol 35 (14) ◽  
pp. 3091-3101 ◽  
Author(s):  
Loon-Seng Tan ◽  
F.E. Arnold ◽  
T.D. Dang ◽  
H.H. Chuah ◽  
K.H. Wei
Keyword(s):  
Rigid Rod ◽  
Aromatic Heterocyclic ◽  
Heterocyclic Polymer
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