Delrin

Delrin is a brand name for polyoxymethylene (POM), a highly crystalline engineering thermoplastic known for its high stiffness, strength, and excellent wear resistance. The Delrin line includes two main POM grades: homopolymer (POM-H) and copolymer (POM-C). POM-H generally provides the highest tensile strength and rigidity but tends to absorb more moisture and can be more sensitive to certain chemical environments. POM-C offers better chemical resistance, lower moisture uptake, and improved dimensional stability, with slightly lower strength than POM-H.

Key properties of Delrin include high mechanical strength and stiffness, low friction, good abrasion resistance, and good dimensional stability over a range of temperatures. It exhibits good resistance to hydrocarbons, fuels, and many solvents, while remaining relatively unaffected by water and many coolants. The material is thermally processable by standard methods such as injection molding and extrusion; it can be machined to tight tolerances and finished with smooth surfaces. Delrin resists creep well for a thermoplastic, though long-term exposure to high temperatures can reduce performance. It has limited UV resistance, so outdoor use often requires stabilizers or protective finishes. POM is hygroscopic and typically needs drying before processing to avoid hydrolysis and dimensional changes.

Common applications include precision gears, bushings, bearings, cams, valve components, fittings, and rollers in automotive, consumer electronics, plumbing, and industrial equipment. Some grades are approved for food contact or medical use, depending on the formulation and certifications. Delrin can be bonded and surface-treated, though bonding to POM often requires specialty primers or mechanical fastening for reliable adhesion. Recyclability is possible where facilities exist for polyoxymethylene plastics.