HIGH-TEMPERATURE STRUCTURAL RESINS.
Abstract
The report summarizes an investigation directed toward the synthesis and evaluation of thermally stable polymers for potential use in fabricating rocket and missile components, and devices requiring deep submergence for long periods of time. Research was concentrated on three aromatic polyheterocyclics, the polyquinoxalines, the polybenzothiazoles, and a novel hybrid polymer, the phenyl-substituted polyquinoxalines. Major emphasis was placed on fabrication of laminates as large as 9 in. x 12 in. x 14 plies, and adhesive bonds from prepreg and tape prepared from stable m-cresol solutions of the polyquinoxalines. Excellent test results were obtained. Polybenzothiazole research also centered on fabrication work which provided 14-ply laminates having high individual flexural strengths and moduli. The successful preparation of an A-B monomer, 3-amino-4-mercaptobenzamide, was accomplished; this was subsequently polymerized to yield poly(2,5-benzothiazole) having polymer decomposition temperatures in air and in helium of 600C and 675C RESPECTIVELY. Novel phenyl-substituted polyquinoxalines were prepared via melt and solution polymerization to yield polymers which exhibited outstanding oxidative stability. A phenyl-substituted diether polyquinoxaline exhibited only a 7% weight loss under isothermal aging at 371C in air after 100 hours and clear, tough, yellow films exhibiting good flexibility were cast from m-cresol solutions. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 17, 1966
- Accession Number
- AD0642043
Entities
People
- Harold H. Levine
- Paul M. Hergenrother