Formulating Gilsonite Waterproofing Compounds
Components
- Bitumen
- Gilsonite (5–20%)
- Fillers
- Fibres
- Solvent or emulsifier
Targets
Softening point, flexibility, adhesion and water absorption.
Example starting formulation (solvent-based coating)
| Component | Typical range | Purpose |
|---|---|---|
| Bitumen 60/70 or oxidized bitumen | 35–50 % | Main binder |
| Gilsonite | 5–15 % | Hardness, heat resistance |
| Mineral filler (limestone, talc) | 10–25 % | Body, reduced cost |
| Fibres | 1–3 % | Sag resistance |
| Aliphatic or aromatic solvent | to viscosity | Application |
Process
- Heat bitumen to 150–180 °C.
- Add gilsonite slowly with stirring until dissolved.
- Cool slightly and add fillers and fibres.
- Cut back with solvent under controlled conditions.
Key tests
Softening point, sag on a vertical panel, drying time, flexibility over a mandrel and water absorption. Adjust gilsonite and filler levels until all targets are met.
Safety
Hot bitumen and solvents are flammable. Use temperature control, ventilation and proper protective equipment.
Recommended product
Coating & Waterproofing Grade Gilsonite
| Property | Typical value | Test method |
|---|---|---|
| Appearance | Black powder | Visual |
| Softening point (R&B) | 150 – 200 °C | ASTM D36 |
| Ash content, max | 5 % | ASTM D3174 |
| Moisture, max | 1 % | ASTM D95 |
| Solubility in TCE, min | 97 % | ASTM D2042 |
| Particle size | ≤ 200 mesh | Sieve |
| Typical dosage | 5 – 25 % of compound | |
| Packing | 25 kg bags palletized; 1 MT jumbo bags. | |
Typical values. The final specification is confirmed in the COA of each shipment.
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