Main brands : Delrin®, Hostaform®, Ultraform®, Ertacétal®, Sustarin®
Polyacetal (POM) is a thermoplastic material with a high degree of crystallinity, characterized by high strength and rigidity. It exhibits good sliding properties and good wear resistance while indicating a low moisture uptake.
Its good dimensional stability and fatigue resistance as well as its excellent machinability make the POM a building material that can be used in many different fields, also for the realization of complex parts;it also makes it possible to satisfy demanding requirements in terms of surface quality.
Strength, rigidity and dimensional stability can be improved by the incorporation of glass fiber fillings, however, resulting in deterioration of sliding properties.
Homopolymers (POM-H, trade name: Delrin) and copolymers (POM-C, trade names: Ultraform, Hostaform) are distinguished.Because of their higher crystallinity, the homopolymers have a slightly higher density, hardness and strength.The copolymers, however, have a resistance to increased chemicals.
Main characteristics of POM :
a high hardness
good impact resistance also at low temperatures
high dimensional stability
resistance to hydrolysis (up to + 60 ° C)
good creep resistance
a low moisture recovery (for saturation of 0.8%)
POM-C has excellent sliding properties and good resistance to wear.This, together with the other very favorable properties of this material, makes POM-C particularly attractive for sliding applications characterized by medium to high stresses.This also applies to areas of application where a high level of humidity or contact with water is to be expected.Given the neighboring static and dynamic coefficients of friction, small clamping cuts are achieved.
Weather and chemical resistance influences
POM-C is not resistant to ultraviolet (UV) radiation. Under the effect of UV rays combined with the oxygen in the air, the surface of the material oxidizes, the color deteriorates, or the material becomes matte according to the case. Under the prolonged effect of UV rays, the material becomes brittle. POM-C is resistant to low concentration acids, alkaline solutions of low and high concentration (pH <4), and oxidizing fluids however attack the brittle material..
Fields of use
POM-C is used in general mechanical engineering, vehicle construction, precision engineering, electrical / electromechanical and telecommunications industries.