The History of Plastics:
The first man-made plastic was created by Alexander Parkes who publicly demonstrated it at the 1862 Great International Exhibition in London. The material called Parkesine was an organic material derived from cellulose that once heated could be molded, and retained its shape when cooled.
Research along the lines of plastics has given a great impetus to research and invention in many other different fields of endeavor. Millions of dollars are spent yearly in plastics research, trying to find new plastics and to improve the existing ones.
Much research will be done in the future to lower the cost of producing plastics so that their consumption will become greater. In spite of the varied and widespread application of plastics in practically every phase of everyday life, the possibilities of this wonderful new material have been by no means exhausted. It seems safe to say that if the application and use of plastics continue to increase at the present rate, we may be living in a "Plastics Age."
Plastic shopping bag:
Plastic shopping bags, carrier bags or plastic grocery bags are a common type of shopping bag in several countries. Most often these bags are intended for one single use to carry items from a store to a home: reuse for storage or trash (bin bags) is common. Heavier duty plastic shopping bags are suitable for multiple uses as reusable shopping bags.
Plastic bags are often made from polyethylene, which consists of long chains of ethylene monomers. Ethylene is derived from natural gas and petroleum.
Patent applications relating to the production of plastic shopping bags can be found dating back to the early 1950s in the United States and Europe, but these refer to composite constructions with handles fixed to the bag in a secondary manufacturing process.
The lightweight shopping bag as we know it today is the invention of Swedish engineer Sten Gustaf Thulin. He developed his idea for forming a simple one-piece bag by folding, welding and die-cutting a flat tube of plastic in the early 1960s for packaging company Celloplast of Norrköping, Sweden. His idea produced a simple, strong bag with a high load carrying capacity and was patented worldwide by Celloplast in 1965.
Celloplast was a well established producer of cellulose film and a pioneer in plastics processing. The company's patent position gave it a virtual monopoly on plastic shopping bag production and the company set up manufacturing plants across Europe and in the US. However, other companies saw the attraction of the bag, too, and US petrochemicals group Mobil overturned the Celloplast US patent in 1977. The Dixie Bag Company of College Park, Georgia, owned and operated by Jack W. McBride ("The Bagman") was one of the first companies to exploit this new opportunity to bring convenient products to all major shopping stores. McBride's Dixie Bag Company, as well as Houston Poly Bag and Capitol Poly were instrumental in the manufacturing, marketing and perfecting of this bag by the early 1980s. Kroger, an Atlanta-based company, agreed to try this innovation. So, the real change in grocery bags did not start until 1982, when the two of America’s largest grocery companies Safeway and Kroger started replacing paper bags with more affordable plastic bags.
Without its plastic bag monopoly, Celloplast's business went into decline, and the company was split up during the 1990s. The Norrköping site remains a plastics production site, however, and is now the headquarters of Miljösäck, Sweden’s largest producer of waste sacks manufactured from recycled polyethylene.
From the mid 1980s on, the use of plastic bags became common for carrying daily groceries from the store to our vehicles and finally to our homes. As plastic bags increasingly replaced paper bags, and as other plastic materials and products replaced glass, metal, stone, timber and other materials, a packaging materials war erupted with plastic shopping bags at the centre of highly publicised battles.
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