Spesifikasi POM Sheet Rod
Polyoxymethylene (POM), also known as acetal, polyacetal and polyformaldehyde, is an engineering thermoplastic used in precision parts requiring high stiffness, low friction and excellent dimensional stability. As with many other synthetic polymers, it is produced by different chemical firms with slightly different formulas and sold variously by such names as Delrin, Celcon, Ramtal, Duracon, Kepital and Hostaform.
Typical applications for injection-molded POM include high performance engineering components such as small gear wheels, ball bearings, ski bindings, fasteners, knife handles, and lock systems. The material is widely used in the automotive and consumer electronics industry.
POM is characterized by its high strength, hardness and rigidity to −40 °C. POM is intrinsically opaque white, due to its high crystalline composition, but it is available in all colors. POM has a density of ρ = 1.410–1.420 g/cm3.
POM homopolymer is a semi-crystalline polymer (75–85% crystalline) with a melting point of 175 °C (347 °F). The POM copolymer has a slightly lower melting point of 162–173 °C.
POM is a tough material with a very low coefficient of friction. However, it is susceptible to polymer degradation catalyzed by acids, which is why it is stabilized - both the homopolymer and the copolymer have chain end groups (introduced via end capping) that resist depolymerization. With the copolymer, the second unit is normally a C2 (ethylene glycol) or C4 (1,4-butanediol) unit, which is introduced via its cyclic acetal (which can be made from the diol and formaldehyde) or cyclic ether (e.g. ethylene oxide). These units resist chain cleavage, because the O-linkage is now no longer an acetal group, but an ether linkage, which is stable to hydrolysis. POM is sensitive to oxidation, and an anti-oxidant is normally added to molding grades of the material.
• High abrasion resistance
• Low coefficient of friction
• High heat resistance
• Good electrical and dielectric properties
• Low water absorption
Harga POM Sheet Rod