Studies of the Breakdown Mechanism of Polymers. VII. The Thermal Decomposition of a Polyhydrazide and of Polyoxadiazoles
Abstract
Poly-1,3-phenylene hydrazide, when heated to 250 C in vacuum, partially undergoes cleavage of the N-N bond to yield isophthalonitrile, water, carbon monoxide, and carbon dioxide. The major part converts to the corresponding polyoxadiazole. Poly- 1,3-and -1,4-phenylene -2,5(1,3,4- oxadiazole) decompose essentially in the 450 to 500 C region to yield isophthalonitrile (also p-aminobenzonitrile in the case of the 1,4-polymer), nitrogen, carbon dioxide, hydrogen cyanide, carbon monoxide, water, ammonia, methane, and hydrogen. The 1,4- polymer decomposes at a slightly higher temperature than the 1,3-polymer and forms less gaseous products and more condensate. The oxadiazole ring degrades before the benzene ring. Initial competing reactions seem to be the removal of nitrogen, further degradation of the remaining ether linkage, and the elimination of oxygen with subsequent cleavage of the residual -C=N-N=C-linkage.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 01, 1972
- Accession Number
- AD0749853
Entities
People
- Gerhard F. L. Ehlers
- Kurt R. Fisch
- Wilbert R. Powell
Organizations
- Air Force Research Laboratory