摘要:

AbstractNew thermostable polymers conlaining plieiiSlsubstitutet1 quiiioxaline and both imide and amide units have been synthesized by low tempera lure solution polycondensation of a diarninophcnylquinoxaline incorporating six‐membered imide rings with diacid chlorides containing five‐rncmbercd irnide rings. Also, poly(phenylquinoxa1ine‐co‐oxadiazole‐irnidc‐amides) havc been prepared using Lhe same mononicrs and 2,5‐bis(p‐arninophenyl)‐1,3,4‐oxadiazole. The thermal stability as well as electrical insulating properties of tlicse poly

ISSN:0323-7648    

DOI:10.1002/actp.1988.010390802

出版商:Akademie Verlag GmbH    

年代:1988

数据来源: WILEY

摘要:

AbstractPoly(esterphenylchinoxaline) wurden durch Niedertemperatur‐Polykondensation von Bis(hydroxyphenylchinoxalinen) mit Säurechloriden aromatischer Dicarbonsäuren sowie durch Polykondensation von Bis(α‐diketonen), die eine Polyestergruppe in der Struktur enthalten, oder deren Gemische mit 1,4‐Bis(phenylglyoxyloyl)benzen mit aromatischen Tetraaminen gewonnen. Es wurde nachgewiesen, daß durch die Einführung von Polystergruppen das gute Eigenschaftsbild der Poly(phenylchinoxaline) weitgehend erhalten bleibt, aber keine Erhöhung der Temperaturbeständigkeit erfolgt. Dagegen bringt die Einführung von Ethinylgruppen, die bei Wärmebehandlung zur Vernetzung führen, eine beachtliche Erhöhung der Wärme

ISSN:0323-7648    

DOI:10.1002/actp.1988.010390803

出版商:Akademie Verlag GmbH    

年代:1988

数据来源: WILEY

摘要:

AbstractThe microstructure of poly(amide‐arylate) based on cardotype polycyclic bisphenol can be changed by heating it at high temperatures at the expense of interchain exchange reactions. In this case, the block segments in polymer chains reduce in size, tending to form copolymers with statistically distributed monomer links in a polymer chai

ISSN:0323-7648    

DOI:10.1002/actp.1988.010390804

出版商:Akademie Verlag GmbH    

年代:1988

数据来源: WILEY

摘要:

AbstractPhosphorus‐containing aromatic polyethers were synthesized by nucleophilic substitution reactions on the basis of bisphenole containing card‐type cyclic substituents of difluorodiphenylsulfone, difluorobenzophenone, and methyl‐bis‐chloromethylphosphine oxide. The polymers are highly heat and fire resistant, and readily soluble in chlorinated hydrocarbons and other oganic s

ISSN:0323-7648    

DOI:10.1002/actp.1988.010390805

出版商:Akademie Verlag GmbH    

年代:1988

数据来源: WILEY

摘要:

AbstractThe methods of mass‐spectrometric thermal analysis, IR spectroscopy, pyrolysis gas chromatography and X‐ray photoelectron spectroscopy were used for the investigation of the effect of benzimidazole (BI) on the thermal behaviour of poly(4,4′‐oxydiphenylene)‐pyromellitamic acid (PAA). It is shown that the formation of a complex of PAA with BI is accompanied by the ordering of amide groups of the polymer, which leads to a decrease in the number of defective units in the resulting

ISSN:0323-7648    

DOI:10.1002/actp.1988.010390806

出版商:Akademie Verlag GmbH    

年代:1988

数据来源: WILEY

摘要:

AbstractPolymeranaloge Umsetzungen von Poly(dichlorphosphazen) mit verschiedenen nukleophilen Reagenzien sowie die chemischen und physikalischen Eigenschaften der so modifizierten Polymere werden betrachtet. Die chemische Uneinheitlichkeit der Poly(organophosphazene), die bei diesen Reaktionen entstehen, bestimmt entscheidend deren Eigenschaften. Die Möglichkeiten der Entstehung von anomalen Gliedern und die Abhängigkeit ihrer chemischen Struktur von Nachbargruppeneffekten werden analysiert. Der Zusammenhang zwischen hoher Molekülmasse und hoher Empfindlichkeit der Polyphosphazene gegenüber Nebenreaktionen wird aufgeze

ISSN:0323-7648    

DOI:10.1002/actp.1988.010390807

出版商:Akademie Verlag GmbH    

年代:1988

数据来源: WILEY

摘要:

AbstractPoly(benzimidazoles) and poly(amidobenzimidazoles) containing sulfur heteroatoms or sulfon groups in the macromolecular chain were synthesized and investigated. Sulfur‐containing aromatic tetramines, diamines and dicarboxylic acids were used as the initial monomers. The produced polymers have sufficiently high molecular weights and are well soluble in usual organic solvent

ISSN:0323-7648    

DOI:10.1002/actp.1988.010390808

出版商:Akademie Verlag GmbH    

年代:1988

数据来源: WILEY

摘要:

AbstractOn base of polyimides with various chemical structures, which are considered to be the main structure types of polyimides, some carbonized products were obtained. By means of pyrolyse gas chromatography and X‐ray photoelectron spectroscopy the chemical changes in the polyimides during heating were studied. A mechanism of the carbonization process is suggeste

ISSN:0323-7648    

DOI:10.1002/actp.1988.010390809

出版商:Akademie Verlag GmbH    

年代:1988

数据来源: WILEY

摘要:

AbstractThe study of the peculiarities of the phase behaviour of solutions of poly(amic acids) (PAA) on the basis of low‐active dianhydride of tricyclodecentetracarboxylic acid in dioxane permitted to establish the conditions of their existence in the mesomorphic state. Under these conditions an intensive growth of the PAA chains was observed, the polymerization degree increased from 7 up to 90, and the intrinsic viscosity of the polymers increased from 0.1 up to 1.2 dl/

ISSN:0323-7648    

DOI:10.1002/actp.1988.010390810

出版商:Akademie Verlag GmbH    

年代:1988

数据来源: WILEY

摘要:

AbstractThermostable high molecular weight poly(benzimidazole imides) were obtained by the reaction of bis‐benzimidazoles with bis‐maleimides at 110 to 120°C in DMF in presence of carboxylic acids. The polymers are light‐coloured compounds, soluble in amidic solvents, DMSO, formic and sulfuric acids. Their structure was identified by elemental analysis and IR spectroscopy. Pressed materials of the polymers proved to possess proper dielectric and mechanical prop

ISSN:0323-7648    

DOI:10.1002/actp.1988.010390811

出版商:Akademie Verlag GmbH    

年代:1988

数据来源: WILEY