Hollow Glass Sphere for Emulsion Explosives
Hollow glass microspheres primarily function as physical sensitizers, density modifiers, and emulsion stabilizers in emulsion explosives, while also improving detonation performance and storage stability.
I. Physical Sensitization
– Providing Stable “Hot Spots”: Hollow, sealed glass microspheres (particle size over 110 μm) are uniformly dispersed, trapping gas inside. Upon detonation, they undergo adiabatic compression, instantly heating to 400–600 °C, forming numerous smoldering hot spots that trigger oil-phase combustion and oxidizer decomposition, ensuring reliable detonation.
– Stable Sensitization Effect: Compared to chemical foaming agents (bubbles easily escape, density is difficult to control) and expanded perlite (easily broken, low closed-cell rate), glass microspheres are pressure-resistant, have intact closed cells, and provide long-lasting sensitization.
II. Precise Density Adjustment
– Low density (0.18–0.22 g/cm³): Adding 2%–4% (by mass) can adjust the explosive density to the ideal range (typically 0.95–1.1 g/cm³), balancing detonation velocity and work capacity. – Controllable density and batch stability, suitable for mechanized charges and deep-water blasting.
III. Improved Emulsion Stability (Anti-stratification, Anti-demulsification)
– After oleophilic surface treatment, it tightly binds with the oil phase, forming a three-dimensional network that inhibits the settling of the aqueous phase and the floating of the oil phase.
– Improved resistance to crystallization and settling; shelf life can reach over 180 days; minimal sympathetic detonation distance and saturation decay.
IV. Improved Detonation Performance
– Increased detonation velocity, saturation, and sympathetic detonation distance; more stable energy output; underwater explosion energy reaches its peak at approximately 4% addition.
– Reduced detonation sensitivity fluctuations; reduced risk of mis-explosion and partial detonation; improved operational safety.
V. Process and Safety Advantages
– Good fluidity and easy dispersion; less prone to breakage of mixed/charged materials; low dust content; chemically inert (acid and alkali resistant, non-reactive); safe production.
– Glass microspheres undergo special surface treatment with good oleophilicity; no additional consumption of the oil phase; high formulation tolerance.
