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Compare asphalt, bitumen and tar
Short answer
Asphalt is a mixture of bitumen and mineral matter, used for road surfaces and roofing. Bitumen is the pure petroleum binder with good durability and adhesion, used in road construction and waterproofing. Tar is a coal/wood distillate, more temperature-sensitive, used for priming and wood preservation.
Give the comparison (major differences) between asphalt, bitumen and tar.
| Point | Asphalt | Bitumen | Tar |
|---|---|---|---|
| Definition | Bitumen mixed with mineral matter | Hydrocarbon binder, residue from petroleum | Product of destructive distillation of coal/wood |
| Source | Natural deposits or manufactured | Petroleum refining or natural | Coal, wood, peat |
| Mineral matter | Large amount | Very little | Nil |
| Composition | Bitumen + sand/aggregate/filler | Hydrocarbons, mostly aliphatic and naphthenic | Aromatic hydrocarbons, phenols |
| State at 25 °C | Solid or semi-solid | Semi-solid to viscous liquid | Viscous liquid |
| Temperature susceptibility | Medium | Lower | Highest |
| Ageing and weathering | Good | Good | Poor, dries and cracks |
| Adhesion | Good | Very good | Good initially |
| Health effects | Low | Low | Harmful, strong odour |
| Cost | Higher | Medium | Low |
| Main uses | Wearing courses, mastic roofing, floors | Binder in roads, damp-proofing, bituminous felts, paints | Priming, surface dressing, wood and pipe preservation |
In short: asphalt is the bound mixture, bitumen is the pure binder from petroleum, and tar is a coal or wood distillate that is more temperature-sensitive and less durable.
✓ Answer checked by Claude Opus 5.5 (high effort)
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