Acetal (POM) - A thermoplastic produced by the addition polymerization of an aldehyde through the carbonyl function, yielding unbranched polyoxymethylene chains of great length. The acetal resins are among the strongest and stiffest of all thermoplastics, and are characterized by good fatigue life, low moisture sensitivity, high resistance to solvents and chemicals, and good electrical properties. Because of these properties, acetals often compete with nylons for many of the same applications. Acetals may be processed by conventional injection molding and extrusion techniques. The main area of application for acetal is industrial and mechanical products.