Effect of Different Plasticizers on the Properties of PBXN-111Underwater Explosive

PBXN-111 is widely used as a common plastic bonded explosive in warhead of several navy weapons. This charge is based on HTPB resin and is prepared via cast-cure method. Isodecyl pelargonate (IDP) as inert plasticizer is commonly used in PBXN-111 formulation. Considering the limitations of IDP preparation, in this research the effects of applying dioctyl adipate (DOA) and dioctyl sebacate (DOS) - instead of IDP- on the density, tensile strength, elongation, hardness and glass transition temperature of PBXN-111 is investigated. Results indicated that the measured parameters for all samples are within the requirements specified in MIL-E-82902. It has also shown that this replacement has no perceptible effects on density and hardness of PBXs. But it caused to the tensile strength and elongation enhanced obviously and reached respectively to 100.6 psi and 21.2% in PBX sample containing DOS. Based on differential scanning calorimeter (DSC), glass transition and thermal stability of this sample are -90 °C and 202 °C respectively. This charge has vacuum thermal stability of 0.05 ml/g/48h, impact sensitivity of 12.5 N.m and friction sensitivity of 8 kg.F. PBX containing DOS plasticizer has also no sensitivity to exploding No. 8 commercial electric detonator.