Investigating the Physical–Mechanical Properties and Sensitivity Assessment of Composite Explosive Based on PETN–Silicone Resin

A composite explosive (PETN-SR) was prepared using PETN as filler and commercial silicone resins of M-4511, M-4644 A/B, E640 and A-335 as binder. The ratio of filler to binder was 80:20. The used resins were two components and cured at room temperature (RTV-2). A planetary mixer was used to mix the ingredients of the sample. The particles size distribution of PETN was 100-300 microns. Thermal behavior, sensitivity to impact, sensitivity to friction, sensitivity to discharge electrostatic, and stability in vacuum of the prepared sample were investigated and compared with the reference material of PBXN-301 (PETN and Sylgard resin 182). The interaction of the filler and binder was studied by infrared spectroscopy. The percentage of elongation, tear strength, and elasticity modulus of PETN-SR composite explosive were measured. The results showed that the composite explosive prepared with M-4511 resin has the best mechanical stress-strain properties. Also, impact sensitivity 7.5 J, friction sensitivity 64-68 N, discharge electrostatic sensitivity 75.7 mJ, and stability in vacuum 0.092 ml/g at temperature 100 oC of the prepared sample is competitive with PBXN-301. On the other, the prepared composite explosive showed better elongation but weaker strength compared to the PBXN-301 explosive.