Реферат: Polymers Essay Research Paper Polymers are large

Polymers Essay, Research Paper

Polymers are large molecules

composed of smaller molecules called monomers.

Monomers are produced and either grow together

or are assembled to produce a single polymer.

There are synthetic and natural polymers. Some

examples of natural polymers would be wood,

starches, fingernails, and hair. Synthetic polymers

are usually referred to as plastics. Petroleum, is the

primary monomer used to produce polymers. An

English chemist named Alexander Parkes was the

first scientist to produce the first synthetic polymer

in 1862. John Wesley Hyatt, an American, was

the first person to produce a useable polymer two

years later. He named the product celluloid. The

prime virtue of polymers is a high

strength-to-weight ratio. Industrial-strength

polymers surpass titanium in tensile strength. To

add strength and improve flexibility, polymers are

sometimes fortified with short-fiber additives,

mostly fiberglass. This is known as a polymer

composite. One particular polymer has three times

the strength of tempered steel and is being used in

bullet proof vests. Another composite will be used

to fasten together the sections proposed space

stations. Polymers have also been used in cars,

including the Chevrolet Camaro and the Pontiac

Fiero. New polymers are being created with more

strength and flexibility by combing two chemically

different polymers and producing a block

copolymer. Combinations of block copolymers

and composites and intended for use in booster

rockets and in materials of Earth-orbiting

installations. Most common polymers are usually

solid, but a new class of polymers is being

introduced in a liquid crystal state. Although these

polymers still have the physical characteristics of

liquid, they are structured more like solids. Many

liquid crystals are transparent at one temperature

and colored at another temperature. This makes

them suitable for use in liquid crystal displays, such

as in digital watches, hand-held calculators, and

lap-top computers. A new liquid polymer,

consisting of a mixture of iron and nickel, is being

used to make metal links that can be used in

paper, glass, and on electronic circuit boards.

Despite the development and widespread use of

polymers, scientific understanding is still sketchy.

Polymer development has occurred through trial

and error. Scientific shortcomings are becoming

more apparent in the search for polymers that can

meet the demands for high technology of today.

The new study is on the microstructure of

polymers while still in a liquid state. The purpose is

to learn how the solid-state structure is developed.

The ultimate goal is to be able to predict

properties from a specific material under a

constant set of processing conditions.

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