Structure formation of sulfonated polyphenylquinoxalines in solution and in the solid state

Sulfonated polyphenylquinoxalines with different content of sulfo groups have been synthesized by polymer analogous reactions under different conditions. The rheological properties of these polymers in Nmethylpyrrolidone have been studied. The mechanical properties of films based on sulfonated polyphenylquinoxalines under uniaxial tension have been measured. The structures of the polymers have been examined by AFM.     

N,N′-Di(3-amino-4-nitrophenyl)piperazine and related poly(benzimidazoles)

New poly(benzimidazoles) containing piperazine rings have been prepared via the reductive polyheterocyclization of poly(o-nitroamides) synthesized through the interaction of the new monomer N, N′-di(3-amino-4-nitrophenyl)piperazine with dichlorides of aromatic dicarboxylic acids. The relationship between the characteristics of poly(o-nitroamides) and poly(benzimidazoles) and their chemical structure has been studied.     

New halogen-containing polyimides based on 1,3-bis(3,4-dicarboxyphenyl)-1,1,3,3-tetramethyldisiloxane dianhydride

Previously undescribed halogen-containing polyimides are synthesized via the interaction of 1,3-bis(3,4-dicarboxyphenyl)-1,1,3,3-tetramethyldisiloxane dianhydride with aromatic diamines containing hexafluoroisopropylidene and dichloroethylene groups. The influence of tetramethyldisiloxane, hexafluoroisopropylidene, and dichloroethylene groups incorporated into these polymers on their solubility, heat resistance, thermal stability, and film-forming properties is investigated.     

Synthesis of new bis[p-(phenylethynyl)phenyl]hetarylenes and bis[p-(phenylglyoxalyl)phenyl]hetarylenes

A series of new bis[p-(phenylethynyi)phenyl]hetarylenes was obtained by cross-coupling between heteroaromatic dibromides and phenylacetylene catalyzed by phosphine complexes of palladium in the presence of Cul and an organic base. Bis[p-(phenylethynyl)phe-nyl]hetarylenes were oxidized to the corresponding bis[p-(phenylglyoxalyl)phenylihetarylenes using the I₂-DMSO system.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 2359–2361, September, 1996.     

An Alternative Approach to the Synthesis of Poly(naphthoylenebenzimidazole)s

An alternative approach to the synthesis of poly(naphthoylenebenzimidazole)s in supercritical carbon dioxide has been accomplished without use of hazardous chemical solvents, which resulted in preparation of high-purity polymers by a more efficient contemporary method. A series of poly(naphthoylenebenzimidazole) s has been obtained at 90°C and 15 MPa for 8 h with the use of a mixture of benzoic acid and benzimidazole as a catalyst. Certain properties of the synthesized polymers have been studied.     

Synthesis and Properties of New Polyphenylquinoxaline-imide-amides

Abstract

New thermostable polymers containing imide and phenylquinoxaline units have been prepared by solution polycondensation of diaminophenylquinoxaline coupled by ether, methylene, or sulfone linkages with diacid chlorides containing preformed imide rings. Solubility, thermal stability, and electroinsulating properties of these compounds are discussed and compared with those of related heterocyclic polymers previously reported.