POM (Polyoxymethylene), also known as acetal or polyformaldehyde, is a thermoplastic plastic with excellent mechanical properties. It is one of the most widely used engineering plastics because of its high strength, stiffness, and wear resistance, as well as its good processability.
POM is a thermoplastic that polymerizes from formaldehyde, resulting in a material that is particularly resistant to wear, has a low coefficient of friction, and excellent chemical resistance. The material is used primarily in applications where mechanical strength and precision are required, such as in gears, bearings, and other parts subject to high loads.
POM comes in two main types: homopolymer POM (with higher mechanical properties) and copolymer POM (with better chemical resistance and stability).
Technical characteristics
Specific gravity
~ 1.41 – 1.43 g/cm³
Tensile strength
~ 60 – 70 MPa
Modulus of elasticity
~ 2.8 – 3.3 GPa
Elongation at break
~ 20 – 50% (depending on type and processing conditions)
Wear resistance
Very high, even better than many metals and other plastics
Melting point
~ 175 – 185 °C
Chemical resistance
Good, resistant to many solvents, acids and bases, but sensitive to strong oxidizers
Temperature range
-40 °C to +120 °C (excellent at both low and higher temperatures)
Coefficient of friction
Very low (excellent for applications where low friction is required)
UV resistance
Moderate, may degrade on prolonged exposure to sunlight
Typical Applications
Mechanical Parts: Gears, bearings, screws, and wheels because of their low coefficient of friction and wear resistance.
Automotive plastic parts: For hoods, fasteners, pumps, and other precision parts.
Medical applications: In medical equipment such as pump mechanisms, atomizers, and invasive instruments (biocompatibility).
Electronic components: In connectors, contacts, and housings for electrical and electronic devices.
Consumer goods: Door handles, latch mechanisms, and fasteners.
Comparison with other plastics (such as POM, PET, PEEK):