Fire hazard reduction using glass bubble (hollow glass microspheres) is a smart and growing approach in materials science, especially for lightweight composites and insulation materials. Here’s how glass bubbles help and what to consider:
How Glass Bubble Reduces Fire Hazards
- Inherently Non-Flammable
- Improved Thermal Insulation
- Reduced Fuel Load
- Char Formation Aid
- Reduced Smoke Production
Glass bubbles are made from soda-lime-borosilicate glass, which is non-combustible. They do not support flame or release toxic gases when exposed to fire.
Due to their hollow structure, glass bubbles reduce thermal conductivity. This acts as a barrier to heat transfer, slowing down flame spread in composite systems.
When used as a filler, they replace a portion of flammable polymer matrix, effectively lowering the total organic content — and thus the available fuel in a fire.
In some formulations, especially with thermosetting resins (e.g., epoxy), glass bubbles can assist in forming a protective char layer that slows combustion.
By reducing the resin content, glass bubble-filled materials typically emit less smoke and fewer toxic gases, which is crucial for safety in enclosed spaces.
Applications Benefiting from Fire Hazard Reduction
- Construction panels and insulation foams
- Automotive and aerospace composites
- Electronic potting and encapsulation materials
- Cables and wire sheathing
- Thermal barriers for lithium-ion battery casings
Enhancing Fire Resistance Further
If maximum fire protection is needed:
- Combine glass bubbles with flame-retardant additives (e.g., aluminum trihydrate, intumescent agents).
- Use with inherently flame-resistant resins, like phenolics or high-performance thermoplastics (PEEK, PPS).
- Apply surface coatings with fire-retardant properties over composites containing glass bubble.