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How Vinyl is Made
The Vinyl Institute

Complex Chemistry Based On Common Salt
Like all plastic materials, vinyl results from a series of processing
steps that convert hydrocarbon-based raw materials (petroleum,
natural gas or coal) into unique synthetic products called polymers.
The vinyl polymer is unusual, however, because it is based only
in part on hydrocarbon feedstocks: ethylene obtained by processing,
or cracking, natural gas or petroleum. The other half of the vinyl
polymer is based on the natural element chlorine.
Chlorine gives vinyl two advantages. First, chlorine is derived
from brine -- a solution of common salt and water, and a readily
available, inexpensive commodity. Thus, vinyl is less sensitive
to fluctuations in the world oil market than are totally oil dependent
polymers.
Second, chlorine has excellent inherent flame retardant properties.
These properties are passed on directly to vinyl end-products,
making vinyl an excellent choice for applications such as electrical
conduit and wiring that require high resistance to ignition and
flame spread.
From Monomer to Polymer Product
Through a chemical reaction, ethylene and chlorine combine to
form ethylene dichloride which, in turn, is transformed into a
gas called vinyl chloride monomer (VCM). A final step, called
"polymerization," converts the monomer into vinyl polymer,
a fine-grained, white powder or resin known as polyvinyl chloride
(PVC), or simply "vinyl."
Vinyl resin, however, is still one step away from being a usable
material: it must be combined with selected chemical additives
and modifiers to achieve the various properties desired in vinyl
end-products. Once these are added, the resulting material --
vinyl compound -- can be converted into an almost limitless range
of applications. (View the above diagram of the vinyl production
process.)
This versatility is yet another reason why vinyl claims such a
large share of the plastics market. It is the only plastic that
can be made thin and flexible enough for wallcoverings, yet rigid
and tough enough for siding on buildings. Depending on the additives
and modifiers used, vinyl compound can be used indoors or outside,
be crystal clear or opaque, and matched to virtually any color
in the rainbow.
Recycling of Vinyl
All types of vinyl products can be recycledand reprocessed into
second-generation products. According to the American Plastics
Council's post-consumer recycling rates study, approximately 9.5
million pounds of post-consumer vinyl were recycled in 1995. In
1995, the world production capacity of VC was 26,400,000 tons.
This translates to .0179% being recycled,
or less than 2 hundredths of a percent is recycled.
The history of vinyl
The world's most versatile plastic had a rather humble beginning:
A rubber scientist during the early 1920s stumbled onto a new
material with fantastic properties during his search for a synthetic
adhesive. Waldo Semon was intrigued with his finding, and experimented
by making golf balls and shoe heels out of the versatile material
called polyvinyl chloride, or PVC.
Soon after his discovery, PVC-based products such as insulated
wire, raincoats and shower curtains hit the market. As more uses
for vinyl were discovered, industry developed more ways to produce
and process the new plastic.
Plants manufacturing PVC began to spring up during the '30s to
meet demand for the versatile material. Just a decade after its
conception, PVC - commonly known as vinyl - was sought for a variety
of industrial applications including gaskets and tubing.
Joining industries across the nation during the '40s, PVC manufacturers
turned their attention to assisting the war effort. Vinyl-coated
wire was widely used aboard U.S. military ships, replacing wire
insulated with rubber. Vinyl manufacturers were working in high
gear as World War II wound down, and they quickly found new markets
for the durable plastic. Following the war, news of vinyl's versatility
and flame-resistant properties spread, leading to dozens of commercial
uses.
Five companies were making PVC at the century's midpoint, and
innovative uses for vinyl continued to be found during the '50s
and '60s. A vinyl-based latex was used on boots, fabric coatings
and inflatable structures, and methods for enhancing vinyl's durability
were refined, opening the door to applications in the building
trades.
Vinyl products quickly became a staple of the construction industry;
the plastic's resistance to corrosion, light and chemicals made
it ideal for building applications. PVC piping was soon transporting
water to thousands of homes and industries, aided by improvements
in the material's resistance to extreme temperatures. Twenty companies
were producing vinyl by 1980.
Today, vinyl is the second largest-selling plastic in the world,
and the industry employs more than 100,000 people in the United
States alone. Vinyl's low cost, versatility and performance make
it the material of choice for dozens of industries such as health
care, communications, aerospace, automotive, retailing, textiles
and construction. Rigid as pipe or pliable as plastic wrap, vinyl
is a leading material of the 21st century.
source: http://www.vinylinfo.org/materialvinyl/history.html
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