Process of preparing heat-resistant polymers
Abstract
Abstract A HIGH MOLECULAR WEIGHT POLYMER HAVING RECURRING UNITS OF THE FORMULA =C(-NH-)-CO->AR(-NH-)-CO->C= WHEREIN AR IS ONE OF THE TETRAVALENT AROMATIC RADICALS SELECTED FROM THE CLASS CONSISTING OF PHENYLENE, DIPHENYLENE, NAPHTHYLENE, DIPHENYLETHER AND DIPHENYLMETHANE AS DERIVED FROM A CONDENSED AROMATIC BIS-(2,4-DIHYDROXYPYRIDINE) COMPOUND BY THE STEPS OF CHLORINATION, ALKOXYLATING, DECARBOXYLATING AND FINALLY POLYMERIZING IN AN ACID MEDIUM AT ABOUT 20-300*C. PREFERRED LONG CHAIN OR RELATIVELY HIGHER MOLECULAR WEIGHT POLYMERS ARE ACHIEVED BY POLYMERIZING IN INORGANIC NON-OXIDIZING ACIDS ESPECIALLY IN POLYPHOSPHORIC ACID. THE POLYMERS ARE ESPECIALLY USEFUL WHERE STABILITY TO HIGH TEMPERATURES AND SOLVENTS IS REQUIRED.
Inventors
- 👤 Hilde Kersten
- 👤 Erhard Siggel
- 👤 Gerhard Meyer
Bibliographic Details
Claims Analysis
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