Urethane Reaction Mechanism on the Amorphous Boron Surface in GAP propellants

✍ Scribed by Yoshio Oyumi; Goro Nakashita

• Publisher: John Wiley and Sons
• Year: 1992
• Tongue: English
• Weight: 404 KB
• Volume: 17
• Category: Article
• ISSN: 0721-3115
• DOI: 10.1002/prep.19920170604

✦ Synopsis

Abstract

Thermal analysis and FT‐IR spectrometry were used to characterize the urethane reaction mechanism of polyglycidyl azide (GAP) propellants with powdered amorphous boron. The amorphous boron added GAP propellant with trimethylol propane (TMP) vigorously gassed of during the cure process and did not complete its urethane reaction. Although it was curable by excess amount of isocyanates, voids or bubbles were trapped inside the propellant grain. Since the powdered amorphous boron was relatively hygroscopic compared to other crystalline metal powders, it might contain boron surface impurities, namely, water, boric acid, and/or boron oxide which disturbed the urethane reaction. TMP was also relatively hygroscopic and played an interesting role on the propellant processing, which was used for cross‐link and surface treatment agent of powdered amorphous boron.