Dynamic mechanical and molecular weight measurements on polymer bonded explosives from thermally accelerated aging tests. II. A poly(ester-urethane) binder [electronic resource].
- Livermore, Calif. : Lawrence Livermore Laboratory, 1981.
Oak Ridge, Tenn. : Distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy.
- Physical Description:
- Pages: 10 : digital, PDF file
- Additional Creators:
- Lawrence Livermore Laboratory and United States. Department of Energy. Office of Scientific and Technical Information
- Restrictions on Access:
- Free-to-read Unrestricted online access
- The molecular weight distribution and dynamic mechanical properties of an experimental polymer-bonded explosive, X-0282, maintained at 23, 60, and 74/sup 0/C for 3.75 y were examined, X-0282 is 95.5% 1,3,5,7-tetranitro-1,3,5,7-tetraazacyclo-octane explosive and 4.5% Estane 5703, a segmented poly(ester-urethane). Two mechanical relaxations at about -24 and 42/sup 0/C were found in the X-0282 aged at room temperature for 3.75 years. A third relaxation at about 85/sup 0/C was found in X-0282 aged at 60 and 74/sup 0/C. The relaxation at -24/sup 0/C is associated with the soft segment glass transition of the binder. The relaxation at 42/sup 0/C is associated with the soft segment melting and may also contain a component due to the hard segment glass transition. The relaxation at 85/sup 0/C is probably associated with improved soft segment crystallite perfection. The molecular weight of the poly(ester-urethane) binder decreased significantly with increasing accelerated aging temperature. A simple random chain scission model of the urethane degradation kinetics in the presence of explosive yields an activation energy of 11.6 kcal/mole. This model predicts a use life of about 17.5 years under the worst military operating conditions (continuous operation at 74/sup 0/C).
- Report Numbers:
- E 1.99:ucrl-85120(vol.2)
E 1.99: conf-810308-4
- Other Subject(s):
- Published through SciTech Connect.
American Chemical Society symposium on the chemistry of engine combustion deposits, Atlanta, GA, USA, 29 Mar 1981.
Hoffman, D.M.; Caley, L.E.
- Funding Information:
View MARC record | catkey: 14657534