Although polyoxymethylene was developed as early as the 1920s, it was not used for several decades due to complications with temperature stability. It was not until the 1950s that the American company DuPont started its production, and later other producers joined.
German chemist Hermann Staudinger is the man behind the thermoplastic polymer called polyoxymethylene, which is more commonly referred to as acetal. Nowadays, this material is widely used for the production of various plastic components, including those for electrical equipment. It is used wherever its unique properties (which we will talk about now) are applied.
Semi-crystalline thermoplastic acetal has excellent wear resistance, heat resistance, flexibility and also high rigidity. It also has decent sliding properties (low coefficient of friction) and is sensorially neutral, i.e. tasteless and odorless. Its low water absorption is also suitable for wet applications. This material also has good impact resistance, even at lower temperatures, when other types of plastic normally crack.
However, the term polyoxymethylene does not refer to just one material. In fact, it is divided into two material categories, in the form of copolymer and homopolymer with the designations POM-C and POM-H, respectively. While POM-C is more resistant to chemical influences and has a lower melting point, the advantages of the POM-H variant include slightly higher density, hardness and strength, thanks to its higher crystallinity.
Homopolymers include, for example, Delrin, which is the name of a polymer patented by DuPont. Examples of copolymers include plastics manufactured under the trade names Hostaform and Ultraform. Plastic processors do not only sell pure POM for further use, but also POM with Teflon, solid lubricants, antistatic additives or glass fibers.