ISSN:
0449-296X
Schlagwort(e):
Physics
;
Polymer and Materials Science
Quelle:
Wiley InterScience Backfile Collection 1832-2000
Thema:
Chemie und Pharmazie
Notizen:
Ordered heterocycle copolymers of high thermal stability were prepared from aromatic dianhydrides reacted with aromatic diamines containing preformed benzoxazole or benzothiazole units. These ordered benzoxazole-imide and benzothiazole-imide copolymers were prepared in the form of their soluble precursor polyamic-acids, which, after fabrication to desired shapes, were converted to the thermally stable polymer. In general, these polymers are more resistant to air oxidation at elevated temperatures than are simple aromatic polyimides, and their thermoöxidative stability is equal to or greater than that reported for benzoxazole or benzothiazole homopolymers. Unlike the o-hydroxyamide precursors to simple polybenzoxazoles, the amic acid precursors to benzoxazole-imide ordered copolymers do not require temperatures above 300°C to complete ring closure nor inert atmospheres to prevent polymer degradation during ring formation. Excellent self-supporting films and film coatings for metals were prepared. Selected compositions were readily spun to excellent fiber.
Zusätzliches Material:
4 Ill.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1002/pol.1969.150070125
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