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=Discovery of Plastics=

Plastics are the wide range materials created by forming long chains of polymers. The name comes from the Greek word "//plastikos//" meaning easily molded


 * **Table of Contents**

Surrounding History  Discovery of Synthetic Plastics  Chemistry of Plastics  Modern Use ||

Surrounding History
Natural plastics such as wax and amber have always been used since the times of ancient people. In the past 200 years however, major developments have taken place, creating the numerous and varying forms of plastic that we have today and use to perform all sorts of everyday tasks. The first man-made plastic was made in 1862 by [|Alexander Parkes] who derived [|Parkesine] from cellulose. Shortly after in 1870 John Hyatt a printer and amateur chemist developed [|Celluloid] by modifying Parkes' methods primarily with heat and pressure. Celluloid was used as a replacement for ivory in many things such as billiard balls and knife handles.

Discovery of Synthetic Plastics
The first truly synthetic plastic was made by a German chemist [|Leo Baekeland]. He invented [|Bakelite] an inexpensive, versatile plastic in 1907. While attempting to find a replacement for shellac, a commercial resin, Baekeland made a material that was hard, light, moldable, and resistant to electricity and heat. His invention of Bakelite was made in the reaction of phenol and formaldehyde under heat and pressure. In 1913 plastic manufacturers General Bakelite Co., Condensite Corp., and Redmanol Chemical Products Company began manufacturing and selling Bakelite. After the invention of Bakelite the improvements to plastics increased exponentially. The most important of which include Polystrene, [|Polyvinyl chloride] (PVC), Polymethyl metharcrylate, and Polyurethane. In the 1930's Harvard chemist Wallace Carothers invented the first purely synthetic plastic, polyamise also known as nylon. Nylon was a hugely successful plastic used in fabrics for clothing all the way to gears for mechanical parts in cars. Many more plastics continued to be invented and still are up to this day.

Chemistry of Plastics
Plastics are essentially [|polymers], which are long strands of identical [|monomers]. This strand can be a three or two dimensional construction, depending on the chemical product. A monomer can be a repeating group of hydrogen, carbon, oxygen, or combination of other [|elements]. There are many plastics, or polymers that exist in nature already. Starch from a plant, or DNA/RNA in bacteria are polymers which serve specific purposes. Many polymers are made of hydrocarbon, or have carbon since it can easily chemically bond. Plastics may also alter in appearance due to their molecular arrangement. A typical modern plastic such as food wrapping has an amorphous molecular arrangement. This is important to control whether or not a plastic is opaque or transparent. The molecular structure of the polymer chain, depending on if it is structured in a way that even light cannot pass through can determine its characteristics. Plastics arranged in crystalline molecular structure may be more stable, resistant, and tough. Due to the nature of plastics, there is almost no limit to the color, characteristic, or use of a synthetic plastic.

Modern Use
There are many advantages to using plastic in our modern lives. The characteristics of polymers allow us to use plastics as containers, film, lenses, construction materials, or even insulators. Plastics are typically lightweight and can be made flexible or sturdy. This is capitalized in uses such as grocery bags (2lbs of plastic holds about 10 gallons of water, where it may require 8lbs of steel), and packaging. Since plastics are usually very lightweight, engineers who design with mass as a criteria may choose plastic. For example, seven trucks loaded with paper bags carry the same amount of bags as one truck carrying plastic bags. Not only is this more resourceful, it is more economic. Plastics have seeped into our lives at an exponential rate since its discovery of manufacturing polymers. It would be impossible to live a modern life without acknowledging plastic.

media type="youtube" key="cMIxY_6Rujs&hl=en&fs=1" height="344" width="425" How Plastic Bags are Made

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Sources http://www.plastiquarian.com/ind1.htm http://www.americanchemistry.com

Image Citations http://www.lakewoodconferences.com/direct/dbimage/50241031/Plastic_Toy.jpg

http://farm1.static.flickr.com/131/367094458_90686f7c20_m.jpg

http://cache.eb.com/eb/image?id=69081&rendTypeId=4

http://www.greenfacts.org/glossary/images/polymer.gif