Flame Retardant Polyphosphazenes.
Abstract
Six polyphosphazene compositions were prepared by reaction of three bis-tertiary phosphines with two phenyl-s-triazine derived diazides. The diazides and two of the bisphosphines were synthesized since none of these was commercially available. One of the bisphosphines and one of the diazides were successfully prepared for the first time. All six polyphosphazenes produced were completely characterized, four of them were furthermore subjected to isothermal gravimetric analysis, smoke density measurements, flammability and oxidative thermal degradation testing. The results of the characterization studies indicate that only low molecular weight oligomers, possibly of a cyclic structure, were obtained in the polymerization reactions. Despite this, however, two of the materials showed no weight loss after 96 hr at 200 deg. C, one did not auto-ignite at 500 deg. C In air, and all four self extinguished when exposed to a flame as soon as contact between flame and resin was lost. The only toxic decomposition products to be concerned about were found to be hydrogen cyanide and benzene. Carbon monoxide, if formed, was present below detection limits. Under the conditions employed it was proven, however, that the quantities of toxic products are greatly reduced if no ignition takes place, e.g., if thermal decomposition proceeds at a sufficiently low rate.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1973
- Accession Number
- ADA307197
Entities
People
- D. W. Karle
- K. L. Paciorek
- R. H. Kratzer