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Plastic - A Primer
What is plastic?
A plastic is a type of synthetic or man-made polymer; similar in many ways to natural resins found in trees and other plants. Webster's Dictionary defines polymers as: any of various complex organic compounds produced by polymerization, capable of being molded, extruded, cast into various shapes and films, or drawn into filaments and then used as textile fibers.American Chemistry
Plastic is the general term for a wide range of synthetic or semisynthetic polymerization products. They are composed of organic condensation or addition polymers and may contain other substances to improve performance or reduce costs.Wikipedia
In a nutshell, plastic is made by combining monomers into polymers under great heat and pressure in a process called polymerization. Each manufacturer has its own proprietary formula for each plastic. And each uses a variety of additives such as plasticizers for flexibility, UV filters for protection from sunlight, antistatic agents, flame-retardants, colorants, antioxidants, and more. Heavy metals such as cadmium, mercury, and lead are common additives. Paul Goettlich, Mindfully.org
How is it produced?
Oil and natural gas are the major raw materials used to manufacture plastics. The plastics production process often begins by treating components of crude oil or natural gas in a "cracking process." This process results in the conversion of these components into hydrocarbon monomers such as ethylene and propylene. Further processing leads to a wider range of monomers such as styrene, vinyl chloride, ethylene glycol, terephthalic acid and many others.American Chemistry
7 main types of plastics
#1 PET (Polyethylene terephthalate): fizzy drink bottles, oven-ready meal trays and water bottles
#2 HDPE (High-density polyethylene): milk bottles, detergent bottles, yogurt and margarine tubs, cereal box liners, and grocery, trash and retail bags
#3 PVC (Polyvinyl chloride): cling film (plastic food wrap), vegetable oil bottles, loose-leaf binders, and construction products such as plastic pipes
#4 LDPE (Low-density polyethylene): dry cleaning bags, produce bags, trash can liners, bread and frozen food bags and squeezable bottles such as mustard and honey
#5 PP (Polypropylene): ketchup bottles, medicine bottles, aerosol caps, and drinking straws
#6 PS (Polystyrene): compact disc jackets, grocery store meat trays, egg cartons, aspirin bottles, packaging Styrofoam peanuts and plastic tableware
#7 Other: three- and five-gallon reusable water bottles, certain kinds of food containers and Tupperware
Earth 911
What is it used for?
The packaging industry is primarily responsible for the use of plastics. Clear low-density polyethylene plastic wrap coverings account for most of the plastic packaging materials, followed closely by high-density polyethylene plastic films used in trash bags and containers. Certain plastics have excellent impenetratable properties, acting as barriers to oxygen, water vapour, and other substances which are to be kept either in or out of containers.
Plastic is also used in construction, automobiles, electronic devices and around the house in a host of items including shower heads, dishes, skylights, eye glasses, cameras, floor waxes, carpets, piano keys, switch cover plates, buttons, door knobs, papers, shoe heels, toothbrush handles, cutlery handles and combs. ...more
The Plastic Bag Scourge... a few facts
Bottled Water Surge
Bisphenol A
Ecological Footprint
Biodegradable Plastic
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