Strained Ring Energetic Binders
Abstract
The use of thermoplastic elastomers (TPEs) containing strained hydrocarbon rings as energetic propellant binders is an attractive approach to increasing the performance of highly oxidized propellant formulations which currently use HTPB as a binder. The recently reported strained-ring elastomeric polymer polybenzvalene (PBV), produced by ring-opening metathesis polymerization (ROMP), is an example of a strained ring polymer. However, PBV is thermally unstable (T(sub onset) = 77 deg C, T(sub max)= 137 deg C) and deflagrates under severe mechanical stretching. In this program several areas were investigated. First, studies to attempt the thermal stabilization of PBV were undertaken. One approach was the partial reduction of the double bonds present in PBV which gave only small increases in thermal stability (Delta T(sub max) = 9 deg C). The second approach was the addition of radical traps to PBV which, again, gave only small increases in thermal stability (delta T(sub max) = 8 deg C). The second area investigated a different strained ring polymer, polyhomobenzvalene (PHBV). PHBV was not found to have the mechanical instability problems of PBV, but was still thermally unstable (T(sub onset) = 66 deg C, T(sub max) = 109 deg C). The last area studied was the application of acyclic olefins as chain-transfer agents during polymer formation which produced difunctional hydroxytelechelic polymers of cyclooctene and cyclooctadiene (as model systems) with good control of molecular weight.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 27, 1993
- Accession Number
- ADA269056
Entities
People
- Jean-pierre Schaller
- Louis F. Cannizzo
- Marc A. Hillmyer
- Robert H. Grubbs