POLYMER
The word Polymer comes from the Greek "poly" meaning many, and "meros", parts
or units. A polymer is a group of many units. You combine many monomers (one
unit) to create a polymer.
Polymer is often used as a synonym for "plastic", but many biological and
inorganic molecules are also polymeric. All plastics are polymers, but not all
polymers are plastics. Plastic actually refers to the way a material melts and
flows.
Commercial polymers are formed through chemical reactions in large vessels
under heat and pressure. Other ingredients are added to control how the polymer
is formed and to produce the proper molecular length and desired properties.
This chemical process is called "polymerization".
A homopolymer results from polymerizing only one kind of monomer. A copolymer
results from using different monomers. Homopolymers have the same repeating unit
while copolymers (which can be random, block, or graft) can vary have different
numbers of repeating units. A terpolymer results from using three different
monomers.
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