Where low wear, high flexural fatigue, creep performance and fuel resistance are some of the key requirements for your applications, POM (polyoxymethylene) could provide the right solution.
POM – also known as acetal or polyacetal – is a highly crystalline, high-performance engineering polymer that displays a broad range of properties, particularly its low coefficient of friction, excellent wear resistance, high modulus and resistance to many solvents and automotive fuels. Basic mechanical properties include high strength and stiffness coupled with good impact strength. Low moisture absorption results in excellent dimensional stability and makes POM an excellent candidate for parts that must exhibit tight tolerances in moist environments.
POM exists as a homopolymer or copolymer.
The homopolymer has slightly higher short-term mechanical properties and melts at a higher temperature, while the copolymer has higher continuous-use temperature, greater alkali resistance and is less affected by long-term exposure to moisture at an elevated temperature.
Copolymers POM delivers a wider processing window, better long-term mechanical properties and superior chemical resistance compared to homopolymers, and are inherently more stable and resistant to thermal degradation during service life. This is because the randomly dispersed comonomer units block polymer “unzipping” under thermal stress, or exposure to hot water or hot alkaline solutions.
POM products are very versatile and as a result, are used in a wide array of applications across many industries. POM may be processed by injection molding, extrusion, compression molding, rotational casting or blow molding.
The polymer can be modified with glass fibers, minerals, conductive fillers, lubricants, pigments and many other additives and used in the following applications:
• Consumer products — Gears, springs, hand tools and toys
• Industrial products — Faucet underbodies, shower heads, pumps, and irrigation equipment and valves
• Appliance components — Gears, timers and pumps
• Information technology products — Gears and bearings
• Transportation — Fuel pumps and fuel system components, control cables, windshield wipers, heater/air conditioner components and interior door handles