Acetal (POM) (Polyoxymethylene)

Acetal polymers are semi-crystalline. They offer excellent inherent lubricity, fatigue resistance, and chemical resistance. Acetals suffer from outgassing problems at elevated temperatures, and are brittle at low temperatures. Glass filled, and added lubrication grades are available, flame retardant grades are not.

Applications: Mechanical Automotive, Business Machine and Household Appliance, Components i.e. Slides, Gears, Cams, Bushings, Door Handles and Seat Belt Parts

Advantage

 

High tensile strength with rigidity and toughness
Good impact and solvent resistance
Glossy molded surface
Low static and dynamic coefficients of friction (slippery)
Many grades have FDA and NSF approvals on food and water contact
Replace die–cast metal components

Disadvantage

 

Difficult to bond bond
Poor resistance to acid and bases
Subject to UV degradation

Tensile StrengthFlexural ModulusImpact StrengthMax Temp.Chemical Resistance
6000-22,000 psi120,000-170,000 psi8-2 ft-lb/in notched izod180°-300°FExcellent