Explosive Strength and Impact Sensitivity of Several PBXs Based on Attractive Cyclic Nitramines

Abstract

Plastic explosives based on different cyclic nitramines with different polymeric matrices were prepared and studied. The used polymeric matrices were fabricated on the basis of polyisobutylene (PIB), acrylonitrile-butadiene rubber (ABR), Viton A, and polydimethyl-siloxane as binders, whereas the nitramines named RDX (1,3,5-trinitroperhydro-1,3,5-triazine), β-HMX (β-1,3,5,7-tetranitro-1,3,5,7-tetrazocine), BCHMX (cis-1,3,4,6-tetranitrooctahydroimidazo-[4,5-d]imidazole) and ε-HNIW (ε-2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane) were used as explosive fillers. Commercial Semtex 10, based on pentaerythritol tetranitrate (PETN), was used for comparison. Impact sensitivity, loading density, ρ, detonation velocity, D, and relative explosive strength (RS) measured by ballistic mortar were determined. It was concluded that plastic BCHMX based on Viton A or PIB-matrix exhibits higher RS compared with PBXs based on RDX and HMX. Correlations between RS and the impact sensitivity, the ρD2 term and the square of the detonation velocity were studied and discussed. The results confirm the well-known fact that increasing the performance is usually accompanied by an increase in the sensitivity of the explosives. In this connection, Viton A enables achieving a high RS, but with a relatively high sensitivity of the PBXs, whereas the polydimethyl-siloxane matrix should perhaps give PBXs with optimum explosive strength and sensitivity parameters.