Plastic is
a material consisting of any of a wide range of synthetic or
semi-synthetic organics that are malleable and can bemolded into
solid objects of diverse shapes. Plastics are typically organic polymers of
high molecular mass, but they often contain other substances. They are
usually synthetic, most commonly derived from petrochemicals, but many are
partially natural.[2] Plasticity is the general property of all
materials that are able to irreversibly deform without breaking, but this
occurs to such a degree with this class of moldable polymers that
their name is an emphasis on this ability.
Due to
their relatively low cost, ease of manufacture, versatility, and imperviousness
to water, plastics are used in an enormous and expanding range of products,
from paper clips to spaceships.
They have already displaced many traditional
materials,such as wood, stone, horn and bone, leather, paper, metal, glass,
and ceramic, in most of their former uses. In developed countries, about a
third of plastic is used in packaging and another third in buildings such as piping used
inplumbing or vinyl siding.[3] Other uses include automobiles
(up to 20% plastic[3]), furniture, and toys.[3] In the developing world,
the ratios may be different - for example, reportedly 42% of India's
consumption is used in packaging.[3] Plastics have many uses in the
medical field as well, to include polymer implants, however the field of plastic
surgery is not named for use of plastic material, but rather the more
generic meaning of the word plasticity in regards to the reshaping of flesh.
The
world's first fully synthetic plastic was bakelite, invented in New York
in 1907 by Leo Baekeland[4] who coined the term 'plastics'.[5] Many
chemists contributed to the materials scienceof plastics, including Nobel
laureate Hermann Staudinger who has been called "the father ofpolymer
chemistry" and Herman Mark, known as "the father of polymer
physics".[6] The success and dominance of plastics starting in the
early 20th century led to environmental concerns regarding its slow
decomposition rate after being discarded as trash due to its composition of
very large molecules. Toward the end of the century, one approach to this
problem was met with wide efforts toward recycling.
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