GAP Analyses: NMR Methods
Abstract
Glycidyl azide polymer (GAP) is under investigation as an energetic binder for several military applications. Hydroxy terminated GAP, where two, three, or four end groups per molecule are present has been studied for use in urethane cured formulations. A key to understanding the cure behavior in these systems is an accurate measure of hydroxy equivalent weight. NMR investigations of equivalent weights have been undertaken in our laboratory and we will briefly describe the results for several GAP lots available to us. NMR is quite sensitive to the initiator present and we can easily distinguish butane diol or trimethylol propane initiated systems. In addition, the carbon-13 NMR spectra of GAP samples were studied in detail allowing for assignment of all relevant resonances due to main chain and terminal groups. Samples of GAP azide, a moderate molecular weight plasticizer, were also studied. This material was found to contain small levels of hydroxy functionality, on the order of one per 10,000 glycidyl groups, however, it was also clear that methylene chloride solvent remains behind even after solvent stripping and chromatographic separation. This made the analysis of hydroxy equivalent weight difficult of coincidental overlap of these resonances. Glycidyl azide polymer, Functionality, GAP Azide, NMR Characterization.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 1993
- Accession Number
- ADA270611
Entities
People
- A. J. Freyer
- D. A. Ciaramitaro
- D. J. Harris
- M. L. Chan
- R. A. Nissan
Organizations
- Naval Air Warfare Center Weapons Division