POM, commonly called acetal, is a highly crystalline thermoplastic polymer exhibiting excellent wear resistance in both wet and dry environments. Both homopolymers and copolymers versions are available for this engineering plastic. Because of higher crystallinity of homopolymer, it has slightly higher density, hardness, strength, and fatigue resistance. Copolymer has better thermal stability, chemical resistance, and ease of processing.
- Good Creep Resistance & High Dimensional Stability even at low temperatures.
- High Strength, Rigidity and Toughness over a wide temperature range.
- Resistant to Chemicals:Good resistance to organic solvents and synthetic detergents...
- Good Resistance to Hydrolysis:Excellent hydrolysis resistance up to 140 °F
- Good Electric Insulation
- Low Water Absorption
gears, bearings, bushings, rollers, conveyors, window guides, sliding & spring elements, insulators, speaker grilles, fasteners, ski-bindings, zippers, lighters, fuel pump plates, aerosol valves, watch bracelets, medical devices, snap-fits, impellers, furniture components, coils…

Item | Property | Test Method | Unit | POM-H | POM-C |
---|---|---|---|---|---|
Physical | Density | ASTM D 792 | g/cm3 | 1.41 | 1.14 |
Water Absorption | ASTM D 570 | % | 0.16 | 0.22 | |
Rockwell Hardness | ASTM D 785 | R scale | 120 | 120 | |
Mechanical | Tensile Modulus | ASTM D 638 | psi | 4.0 × 105 | 4.5 × 105 |
Tensile Strength | ASTM D 638 | psi | 11,000 | 9,430 | |
Flexural Modulus | ASTM D 790 | psi | 4.5 × 105 | 3.9 × 105 | |
Flexural Strength | ASTM D 790 | psi | 13,000 | 12,000 | |
Izod Impact | ASTM D 256 | ft-lb/in | 1.0 | 1.0 | |
Thermal | Heat Deflection Temperature | ASTM D 648 | °C/°F | 121 / 250 | 110 / 230 |
Linear Coefficient of Expansion | ASTM D 696 | in/in/°F | 4.7 × 10-5 | 5.4 × 10-5 | |
Flammability | ASTM D 635 | - | HB | HB | |
Electrical | Electrical Volume Resistivity at 50% RH | ASTM D 257 | Ω/cm | 1015 | 1015 |
Dielectric Constant | ASTM D 150 | 1 MHz | 3.7 | 3.8 | |
Dissipation Factor | ASTM D 150 | 1 MHz | 0.005 | 0.005 | |
Dielectric Strength | ASTM D 149 | V/mm | 33,000 | 40,000 |