High-density polyethylene (HDPE) or polyethylene high-density (PEHD) is a thermoplastic polymer produced from the monomer ethylene. It is sometimes called "alkathene" or "polythene" when used for HDPE pipes. With a high strength-to-density ratio, HDPE is used in the production of plastic bottles, corrosion-resistant piping, geomembranes and plastic lumber. HDPE is commonly recycled, and has the number "2" as its resin identification code.
P 1961b (OTTO) Polyethylene (HDPE) Cas 9002-88-4 - used in products and packaging such as milk jugs, detergent bottles, butter tubs, garbage containers, and water pipes.