Polymer chemistry

Polymer chemistry
The simple substance ethylene is a gas
composed of molecules with the formula
CH CH . Under certain conditions, many
ethylene molecules will join together to
form a long chain called polyethylene, with
the formula (CH CH ) , where n is a
variable but large number. Polyethylene is a
tough, durable solid material quite different
from ethylene. It is an example of a
polymer , which is a large molecule made
up of many smaller molecules (monomers),
usually joined together in a linear fashion.
Many naturally occurring substances,
including cellulose , starch, cotton, wool,
rubber, leather, proteins, and DNA, are
polymers. Polyethylene, nylon, and acrylics
are examples of synthetic polymers. The
study of such materials lies within the
domain of polymer chemistry, a specialty
that has flourished in the 20th century. The
investigation of natural polymers overlaps
considerably with biochemistry, but the
synthesis of new polymers, the
investigation of polymerization processes,
and the characterization of the structure and
properties of polymeric materials all pose
unique problems for polymer chemists.
Polymer chemists have designed and
synthesized polymers that vary in hardness,
flexibility, softening temperature, solubility
in water, and biodegradability. They have
produced polymeric materials that are as
strong as steel yet lighter and more
resistant to corrosion. Oil, natural gas, and
water pipelines are now routinely
constructed of plastic pipe. In recent years,
automakers have increased their use of
plastic components to build lighter vehicles
that consume less fuel. Other industries
such as those involved in the manufacture
of textiles, rubber, paper, and packaging
materials are built upon polymer chemistry.