Manufacture and Composition
Traditional plastic bags are usually made from polyethylene, which consists of long chains of ethylene monomers. Ethylene is derived from natural gas and petroleum. The polyethylene used in most plastic shopping bags is either low-density (resin identification code 4) or, more often, high-density (resin identification code 2). Color concentrates and other additives are often used to add tint to the plastic. Plastic shopping bags are commonly manufactured by blown film extrusion.
Read more about this topic: Plastic Shopping Bag
Famous quotes containing the words manufacture and, manufacture and/or composition:
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—Elizabeth Stuart Phelps (1844–1911)
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—Mary Kay Blakely (20th century)