3D direct writing and micro detonation of CL-20 based explosive ink containing O/W emulsion binder

Abstract

The booming development of DIW technology present an unprecedented prospect in energetic materials field and has attracted great interest due to its relative simplicity and high flexibility of manufacturing. Herein, a novel CL-20 based explosive ink formulation have been developed successfully for MEMS initiation systems via DIW technology. We designed PVA/GAP into an oil-in-water(O/W)emulsion, in the way that the aqueous solution of PVA as water phase, the ethyl acetate solution of GAP as oil phase, the combination of Tween 80 and SDS as emulsifier, BPS as a curing agent of GAP. The ideal formulation with good shear-thinning rheology properties and clear gel point was prepared using only 10 wt% emulsion. The dual-cured network formed during the curing process made the printed sample have good mechanical properties. The printed samples had satisfactory molding effect without cracks or fractures, the crystal form of CL-20 not changed and the thermal stability have improved. Deposition of explosive inks via DIW in micro-scale grooves had excellent detonation performances, which critical detonation size was 1 × 0.045 mm, detonation velocity was 7129 m/s and when the corner reaching 150° can still detonated stably. This study may open new avenues for developing binder systems in explosive ink formulations.

Keywords

• Direct writing
• Explosive ink
• Emulsion binder system
• CL-20 based energetic composites
• Micron detonation