Acetal (POM)
Acetal Copolymer (POM-C) – Dimensionally Stable Engineering Plastic for Precision Components
Acetal copolymer (POM-C) is the polyoxymethylene copolymer variant offering slightly lower mechanical properties than Delrin homopolymer but improved chemical resistance, lower shrinkage, and better dimensional stability in hot water and alkaline environments. It is widely used for precision valves, gears, and pump components in chemical handling and plumbing applications.
Key Properties
- Tensile Strength: 63 MPa
- Yield Strength: 55 MPa
- Service Temperature: Up to 166°C
- Density: 1.41 g/cm³
- Key Advantage vs Delrin (homopolymer): Better chemical resistance and lower shrinkage
- Standard: ASTM D4181
Common Applications
Precision gears, valve bodies, pump housings, pipe fittings for hot water systems, conveyor components, and applications requiring the dimensional stability of acetal with improved resistance to alkaline or aqueous environments.
Material properties
| Material name | Acetal (POM) |
|---|---|
| Type | Plastics |
| Standard code | ASTM D4181 |
| Tensile strength (MPa) | 63 |
| Yield strength (MPa) | 55 |
| Fatigue strength (MPa) | 28 |
| Elongation (%) | 30 |
| Hardness (Brinell) | — |
| Density (g/cm³) | 1.41 |
| Electrical resistivity (µΩ·in) | — |
| Thermal conductivity (W/m·K) | 0.4 |
| Melting range (°C) | 166 |
| Weldability | N/A |
| Formability | Good |
| Shear modulus | 1.4 |
| Industry code | acetal |