POM

Description

POM

Scope of application

Polyformaldehyde is suitable for making wear-resistant parts, drive parts, as well as chemical industry, instruments and other parts. It has rigid, high wear resistance characteristics. It is mainly used in gear, bearing, auto parts, machine tools, instrument internals and other products.

Application

Polyformaldehyde can replace most of the non-ferrous metals, cars, machine tools, instrument inner parts, bearings, fasteners, gears, spring sheets, pipes, transportation belt accessories, electric water cooker, pump housing, drillers, faucets, etc.

mechanical property

POM has high strength, rigidity, good elasticity and good wear resistance. The mechanical properties of the system are excellent, the specific strength can reach 50.5mpa, the specific stiffness can reach 2650mpa, which is very close to the metal. The mechanical properties of POM are smaller with temperature, and the change of copolymerization POM is slightly larger than that of homopolymer POM. POM has higher impact strength, but the conventional impact is lower than that of ABS and PC; POM is sensitive to notch, and notch can reduce impact strength by 90%. The fatigue strength of POM is very prominent. After 10 alternating load, the fatigue strength can reach 35MPa, while PA and PC are only 28Mpa. The creep of POM is similar to PA, which is only 2.3% at 20 ℃, 21MPa and 3000h, and is very little affected by temperature. The friction coefficient of POM is small, and the wear resistance is good (pom>pa66>pa6>abs>hpvc>ps>pc), the limit PV value is very large and the self-lubricating property is good. POM products are prone to scream noise when they are subjected to high load.

Electrical performance

The electrical insulation of POM is good, almost not affected by temperature and humidity; The dielectric constant and dielectric loss change little in a wide range of temperature, humidity and frequency; Excellent arc resistance and can be maintained at high temperature. The dielectric strength of POM is related to the thickness, which is 82.7kv/mm when the thickness is 0.127mm and 23.6kv/mm when the thickness is 1.88mm.

Environmental performance

POM intolerance of strong alkali and oxidant, has a certain stability to acrylic acid and weak acid. POM has good solvent resistance, resists hydrocarbons, alcohols, aldehydes, ethers, gasoline, lubricants, and weak bases, etc., and maintains considerable chemical stability at high temperature. Small water absorption and good size stability.

POM has poor weather resistance, long-term UV action, decreased mechanical performance, surface pollination and cracking.

Forming properties

Crystallinary material, narrow melting range, fast melting and solidification, material temperature slightly lower than the melting temperature is crystallization. Moderate liquidity. Small moisture absorption, without dry treatment.