The acetal(POM) in plastic injection molding.
The polyoxymethylene (POM), known as acetal, is one of more common thermoplastics used in ZATEC, for our processes of technical plastic injection molding. This material is assembled in some applications where it is necessary a good tribological behaviour. Therefore, is used to reduce the effects of wear and friction, due to contact between different components, to begin the movement (static coeficient) or during the movement (dinamic coefficient).
Other important point to bear in mind, is the resistance to chemical agents, due to these parts are used in assemblies where greases and oils are applied. If you need a good resistance to chemical agentes, the POM is a good choice depending on final exact application. In this phase is where we can collaborate with our customers thanks to our expertise of more than 30 years.
The POM is a material of elevated stiffness, hardness, and toughness with an elevated density(1,42 gr/cm3), and therefore goo good resistantce to creep, besides of good behaviour to hydrolysis. By this reason is used in several applications in automotive like gears in the power windows, components in fuel tank…
Homopolymer and Copolymer POM
Sometimes the differences are not so clear, depending on commercial agent of each brand, with different opinions about it. More or less, we can say as follows:
Homopolymer POM, it has better tensile strength, ultimate elongation, weariness and hardness.In general, best mechanical properties. Nevertheless, the injection process is more complicated than copolymer. Altougth, if the material is degradated by an incorrect process, the gas formation is a warning for worker with a tipical smell by mentioned degradation.
POM-Copolymer, has best stability thermical and degradation, increasing the useful life of plastic parts in long-term effects, besides of more chemical resistance. On the other hand, POM-copolymer is processed more easily than homopolymer.
The POM(homopolymer and copolymer) is not a material to colour easily like other thermoplastics. When we use masterbatch, the composition of color pigments can influence in the quality of melted material, due to some additives could affect to degradation of POM.
If you have a project that requires a plastic part injectd with this raw material, we will be pleased to help you. Do not doubt to contact us.