Before we dig into talking about Acetal, an important thing to note is that although Delrin and Acetal are similar materials, they are not the same! Delrin is a DuPont trade name for acetal homopolymer, while the name "acetal" is most commonly referring to acetal copolymer. The difference between them is slim, but worthy of mention.

Ultra High Molecular Weight Polyethylene aka UHMW is one of the most commonly used thermoplastics materials in the world. There are many reasons for this, but most engineers love UHMW for its excellent abrasion resistance, low coefficient of friction and it's tremendous impact resistance.

Nylon MD is a blend of Nylon and a Molybdenum Disulfide (MD) specifically designed to enhance the materials thermal, mechanical, and bearing properties. In a nut shell, the MD adder lowers surface friction, improves material strength and rigidity, and even helps to give it better dimensional stability.

High density polyethylene (HDPE) or polyethylene high density (PEHD) is a polyethylene thermoplastic made from petroleum.

PET is a strong, hard, and dimensionally stable material that absorbs very little water. It has good gas barrier properties and good chemical resistance except to alkalis (which hydrolyse it). PET's crystallinity varies from amorphous to fairly high crystallinity; it can be highly transparent and colorless, but thicker sheets are usually an opaque white.