Abstract: Thermoimidization kinetics of polypyromellitamic acids prepared from 2,5-bis(p-amino-phenyl)pyrimidine and 4,4''-diaminoterphenyl have been investigated by IR spectroscopy. It has been shown that the activation energy for the pyrimidine-containing polymer is nearly twice as low as that for the aromatic analog. This is explained by base catalysis of cyclization of the amidoacid fragments by pyrimidine rings in polymer chains. Base catalysis facilitates the process of imidization and favors the formation of polyimidic macromolecules with a lower incidence of defects. Also, the pyrimidine rings obviously catalyze the resynthesis of amidoacid fragments from the anhydride rings and amino groups formed on the destruction of the polymer chain during thermoimidization, and ensure almost complete recovery of the macromolecules with the previous bonds.

Cite: Artemeva V.N. , Kudryavtsev V.V. , Nekrasova E.M. , Sklizkova V.P. , Lyubimova G.V. , Hofman I.V. , Borovik V.P. , Shkurko O.P.
THE ROLE OF THE PYRIMIDINE RING IN THE MAIN-CHAIN OF POLYAMIC ACIDS AND POLYIMIDES .4. INFLUENCE OF PYRIMIDINE RING BASICITY ON THERMOIMIDIZATION OF POLYAMIDOACIDS
Russian Chemical Bulletin. 1994. V.43. N3. P.387-390. DOI: 10.1007/BF01169711 WOS Scopus РИНЦ

Dates:

Published print:

Mar 1, 1994

Identifiers:

Web of science	WOS:A1994QA80900011
Scopus	2-s2.0-34249764928
Elibrary	30893877
OpenAlex	W2615679327

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