CAS 56-81-5: Glycerol (C3H8O3)
Identity
| CAS Number | 56-81-5 |
| Molecular Formula | C3H8O3 |
| IUPAC Name | propane-1,2,3-triol |
| Molecular Weight | 92.09 g/mol |
| SMILES | OCC(O)CO |
| Synonyms | glycerin, glycerine, 1,2,3-propanetriol, E422 |
2D Structure
Physical Properties
| Density | 1.261 g/mL at 25°C |
| Boiling Point | 290.0°C |
| Melting Point | 17.8°C |
| Flash Point | 160.0°C |
| Vapor Pressure | 0.0001 kPa at 20°C |
| Refractive Index | nD = 1.475 |
| Dielectric Constant | ε = 42.5 |
Safety & GHS Classification
Storage: Store in tightly sealed containers. Hygroscopic — absorbs moisture from air. Viscous liquid — warm to reduce viscosity for transfer. Very low toxicity — food-grade chemical.
Material Compatibility Matrix
Plastics
| Material | Rating |
|---|---|
| PTFE | Excellent |
| PVC | Good |
| PE | Good |
| PP | Excellent |
| PEEK | Excellent |
| PVDF | Excellent |
Rubbers
| Material | Rating |
|---|---|
| Viton | Excellent |
| NBR | Excellent |
| EPDM | Excellent |
| Silicone | Excellent |
| FKM | Excellent |
Metals
| Material | Rating |
|---|---|
| Stainless 316 | Excellent |
| Aluminum | Excellent |
| Copper | Excellent |
| Brass | Excellent |
Applications
- Food additive (E422 — humectant, sweetener)
- Cosmetics and personal care (moisturizer)
- Pharmaceutical formulations (cough syrup base)
- E-cigarette liquid (PG/VG mixture)
- Explosives manufacturing (nitroglycerin precursor)
- Lubricant and plasticizer
- Antifreeze additive
- Historical manuscript preservation
External References: PubChem