Plastic

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Introduction to Plastics
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- History and Significance of Polymers
- The Structure of Polymers
- Polymerization and Molecular Structure
- Molecular Arrangement of Polymers
- Characteristics of Polymers
- Forms of Plastics
- Common Plastic Resins Used in Packaging
- Resin Identification Code

History and Significance of Polymers


Plastics are polymers. What is a polymer? The simplest definition of a polymer is something made of many units. Think of a polymer as a chain. Each link of the chain is the "mer" or basic unit that is made of carbon, hydrogen, oxygen, and/or silicon. To make the chain, many links or "mers" are hooked or polymerized together. Polymerization can be demonstrated by linking strips of construction paper together to make paper garlands or hooking together hundreds of paper clips to form chains.
Polymers have been with us since the beginning of time. Natural polymers include such things as tar and shellac, tortoise shell and horns, as well as tree saps that produce amber and latex. These polymers were processed with heat and pressure into useful articles like hair ornaments and jewelry. Natural polymers began to be chemically modified during the 1800s to produce many materials. The most famous of these were vulcanized rubber, gun cotton, and celluloid. The first synthetic polymer produced was Bakelite in 1909 and was soon followed by the first semi- synthetic fiber, rayon, which was developed in 1911.
Did you know?...
The origin of the word "plastics" comes from Greek. Its original Greek root means...