Polyoxymethylene (POM), also known as formaldehyde resin, polyoxymethylene, or polyacetal, is a thermoplastic crystalline polymer known as "super steel" or "Saigang".

Physical and chemical properties:

Polyoxymethylene is a linear polymer with no side chains, high density, and high crystallinity, possessing excellent comprehensive properties.

Polyoxymethylene is a hard and dense material with a smooth and glossy surface, light yellow or white, and can be used for a long time in the temperature range of -40-100 ° C. Its wear resistance and self-lubricating properties are superior to most engineering plastics, and it also has good oil and peroxide resistance. Not resistant to acid, strong alkali, and UV radiation from sunlight.

The tensile strength of polyoxymethylene reaches 70MPa, with low water absorption, stable size, and luster. These properties are better than nylon. Polyoxymethylene is a highly crystalline resin and is the strongest among thermoplastic resins. It has high heat resistance, bending strength, fatigue resistance, excellent wear resistance, and electrical performance.

physical property:

Appearance: White or light yellow solid, smooth and glossy surface.

Density: Homopolymer POM is 1.41-1.43 g/cm ³, while copolymer POM is slightly lower

Melting point: Homopolymer POM is about 162-173 ℃, while copolymer POM is slightly lower.

Water absorption: relatively small (0.2% -0.5%), good dimensional stability in humid environments.

chemical property:

Corrosion resistance: resistant to oil and peroxides, but not to strong acids, alkalis, and ultraviolet radiation.

Thermal stability: The decomposition temperature is about 280 ℃, and strict temperature control is required during processing to avoid decomposition.

End group structure: containing hemiacetal structure, may gradually depolymerize when heated above 100 ℃.

Mechanical properties

Strength: The tensile strength can reach 70 MPa, and it has excellent wear resistance and fatigue resistance.

Hot deformation temperature: homopolymer POM is about 136 ℃, while copolymer POM is slightly lower but has a higher long-term use temperature.