Thermoplastic comparison
POM (acetal) vs Polypropylene (PP)
Every value below is a typical room-temperature figure with its source, test method and conditions — the same dataset that drives the calculators.
| Property | POM (acetal) | Polypropylene (PP) | Difference |
|---|---|---|---|
| Density | 1.41 g/cm³ | 0.905 g/cm³ | POM (acetal) — 56% higher |
| Young's modulus E | 3.1 GPa | 1.4 GPa | POM (acetal) — 2.2× higher |
| Tensile strength | 65 MPa | 34 MPa | POM (acetal) — 91% higher |
| Glass transition Tg | -60 °C | -10 °C | Polypropylene (PP) — 50 °C higher |
| Melting point Tm | 175 °C | 165 °C | POM (acetal) — 10 °C higher |
Where these numbers come from
- CAMPUS plastics database — typical grade datasheet values (campusplastics.com)
- Callister & Rethwisch, Materials Science and Engineering, 10th ed.
Typical room-temperature values for learning and preliminary design; grades vary widely and a supplier datasheet always overrides a textbook figure. Confirm against the datasheet before design work.