Results 131 to 140 of about 1,007 (177)

Polybenzimidazole and polysulfone blends

Polymer Engineering & Science, 1993
AbstractPolybenzimidazole (PBI) and polysulfone (PS) do not form miscible blends; however, the tensile modulus and strength of their blend fibers are comparable to, or better than, that of PBI fibers, depending on process conditions. Fibers spun from an 80/20 PBI/PS solution blend have PBI‐like LOI (limiting oxygen indices) and flame shrinkage behavior.
Tai‐Shung Chung, Morton Glick, Edward J. Powers   +2 more
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Studies on proton conductivity of acid doped polybenzimidazole/polyimide and polybenzimidazole/polyvinylpyrrolidone blends

Polymer Engineering & Science, 2005
AbstractPolybenzimidazole (PBI)/polyimide (PI) and PBI/polyvinylpyrrolidone (PVP) blends were prepared. All of these polymers are suitable for acid doping as a matrix because of the existence of the N‐heterocycle in the polymers, which can eventually be used as proton conductors.
Hongting Pu, Qizhi Liu, Lei Qiao, Zhenglong Yang   +3 more
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Polybenzimidazoles, new thermally stable polymers

Journal of Polymer Science, 1961
AbstractWholly aromatic polybenzimidazoles were synthesized from aromatic tetraamines and difunctional aromatic acids and characterized as new thermally stable polymers. The melt polycondensation of aromatic tetraamines and the diphenyl esters of aromatic dicarboxylic acids was developed as a general procedure of wide applicability.
Herward Vogel, C. S. Marvel
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Polybenzimidazole and butylsulfonate grafted polybenzimidazole blends for proton exchange membrane fuel cells

Journal of Membrane Science, 2012
Abstract In this work, we synthesize two poly(benzimidazole) (PBIs), i.e., medium molecular weight PBIm and high molecular weight PBIh with 〈Mw〉 = 9.16 × 104 and 1.60 × 105 g/mol, respectively, and two butylsulfonate grafted PBIs (PBI-BSs), i.e., PBIm-BS and PBIh-BS.
Hsiu-Li Lin, Chih-Ren Hu, Shiau-Wu Lai, T. Leon Yu   +3 more
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History and Development of Polybenzimidazoles

1986
Aromatic polybenzimidazoles were synthesized by H. Vogel and C. S. Marvel in 1961 with anticipation, later justified, that the polymers would have exceptional thermal and oxidative stability. Subsequently, NASA and the Air Force Materials Laboratory (AFML) sponsored considerable work with polybenzimidazoles for aerospace and defense applications as a ...
E. J. Powers, G. A. Serad
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Catalysts for the preparation of polybenzimidazoles

Journal of Applied Polymer Science, 1994
AbstractThe single‐stage preparation of poly[2,2′‐(m‐phenylene)‐5,5′‐bibenzimidazole] (PBI), from 3,3′,4,4′‐tetraaminobiphenyl (TAB) with isophthalic acid (IPA) in the presence of a catalyst, was explored and developed. The effects of a variety of catalysts on the polymerization of TAB with IPA and/or diphenyl isophthalate were screened and evaluated ...
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THERMOCHEMISTRY OF POLYBENZIMIDAZOLE FOAMS

1977
Abstract : Results are presented of a study of an automatic polybenzimidazole (PBI) polymer. This study included an analysis of the low-boiling, high-boiling, and solid residue fractions resulting from the pyrolysis and nonflaming oxidative degradation of PBI polymer at temperatures up to 1000 deg C.
I.N. EINHORN, D.A. CHATFIELD, D.J. WENDEL   +2 more
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Polymer Structure: Cross-Linking of a Polybenzimidazole

Science, 1963
The torsional braid technique was used to monitor the changes in rigidity and damping characteristics of a polybenzimidazole as it changes from a thermoplastic polymer to a thermoset resin at about 450°C. In an intermediate process the thermoplastic backbone of the polymer becomes flexible.
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polybenzimidazole

2021
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Fluorinated polybenzimidazoles

Polymer Science U.S.S.R., 1964
A.Ya. Yakubovich, G.G. Rozantsev, G.I. Braz, V.P. Bazov   +3 more
openaire   +1 more source