Accession Number:

ADA175842

Title:

NMR Investigations of Liquid Propellant Systems Consisting of Alkyl- and Hydroxylammonium Nitrates. Part 2. Measurement of Carbon-13 Spin-Lattice Relaxation Times and Activation Energies for Molecular Motion in Model Liquid Propellant Systems.

Descriptive Note:

Technical rept.,

Corporate Author:

ARMY ARMAMENT RESEARCH DEVELOPMENT AND ENGINEERING CENTER DOVER NJ ARMAMENT ENGINEERING DIRECTORATE

Personal Author(s):

Report Date:

1987-01-01

Pagination or Media Count:

25.0

Abstract:

Carbon-13 spin-lattice relaxation times and nuclear Overhauser enhancements were measured in four alkylammonium nitrates, isopropyl-, triethanol-, trimeth trimethyl-, and n-butylammonium nitrates. The relaxation mechanism in these compounds was found to be predominantly by dipolar interactions with attached protons. The relaxation times increase with temperature, as expected, but were found to be essentially independent of concentrations. the alkylammonium ions give rise to consistently shorter relaxation times than the corresponding free alkylamines. Attempts are made to interpret these results in terms of ion pairing, ion clustering, molecular associations, and reorientations. The carbon-13 data lead to the conclusion that it is essential to study the nitrogen spin-lattice relaxations at the charge sites in the alkyl- and hydroxylammonium nitrates to get a better understanding of the motional dynamics, solvation effects, and ion clustering phenomena. Studies with nitrogen-15 labeled compounds are proposed.

Subject Categories:

  • Ammunition and Explosives
  • Atomic and Molecular Physics and Spectroscopy

Distribution Statement:

APPROVED FOR PUBLIC RELEASE