PubLISHED
2022
CategoRY
Materials / Polyoxymethylene

POLYOXYMETHYLENE (POM)

Chemically known as Polyoxymethylene, but commercially referred to as polyacetal or acetal resin, POM is a semicrystalline thermoplastic material, obtained by extrusion and consisting of chains, within which a methylene group and an oxygen atom are repeated. This characteristic gives the material high strength while ensuring a low cost, a factor that is by no means negligible.

POM can represent a kind of intermediate
element between a metal and other ordinary plastics, thanks to the perfect combination of stiffness and lightness, tensile strength, as well as resistance to impacts, fatigue, solvents, fuels, moisture and abrasion. It also exhibits an excellent coefficient of friction, elasticity and dimensional stability. The latter, together with the excellent workability and the low cost, make polyoxymethylene a highly versatile engineering material, even for complex components.

 

Currently, we can find POM-C and POM-H on the market. Both belonging to the same polymeric family, they differ, however, in their molecular structure and, consequently, in their mechanical properties, arising from a different production method. Without going too far into the chemical peculiarities, both materials have very common features, however, POM-H (homopolymer), has better mechanical properties, resistance to creep, wear and friction in the short term, as well as a higher adaptability to temperatures. POM-C (copolymer) has the same characteristics, but provides better long-term performance, as well as excellent chemical and oxidation resistance.

 

These distinctive traits make polyoxymethylene truly versatile and suitable for multiple applications and manufacturing sectors, such as the electrical, mechanical, electronic, pharmaceutical and food, thus ensuring a variety of benefits to those who use it. This resin is particularly suitable to replace precision metal parts, such as watch gears, levers, bearings, screws, pipe fittings, hinges, diving equipment, bicycle parts, valve parts to dispense hot and cold water, and many other items. The most common methods to process this resin are injection molding and extrusion, but blow molding and rotational molding are also possible.