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Disposing of Unwanted Polymers.

Although polymers are very useful materials,
there are problems with the disposal of unwanted articles.


Why not Bury Unwanted Polymers in the Ground?

Many polymers made from fossil fuels are not biodegradable.
This means that decomposers (bacteria and fungi)
will not break them down into simpler substances.
If unwanted polymers are put in landfill (buried in the ground)
they simply remain as polymers in the ground.

Products from plant material (wood, paper, cotton etc.) are
biodegradable. When buried, bacteria and fungi break
them down into useful nutrients for further plant growth.
Nature recycles its own products!


Why not Burn Unwanted Polymers?

Many polymers are a fire hazard. People often die from
the smoke produced by burning polymers in house fires,
long before the fire itself reaches them. Polymers produce
toxic materials (poisons) when they are burnt,
in addition to the expected products of combustion
of hydrocarbons, which are water, carbon dioxide,
carbon monoxide and carbon (soot).

Those polymers that contain chlorine (PVC for example)
also produce hydrogen chloride on burning.
Those that contain nitrogen (nylon for example)
produce hydrogen cyanide when they are burnt.
Hydrogen cyanide is extremely poisonous.
Burning polymers is not a good way of disposing of them.


What are the Solutions to the Disposal of Unwanted Polymers?

Recycling.

Polymers are increasingly being recycled. Recycling polymers
is not as cost effective as recycling metals, but we don't want to
live with piles of (unrotting) plastic and recycling is a better
use of the finite raw materials (fossil fuels) that make polymers.

Making Biodegradable Polymers.

Research into producing biodegradable polymers
(making polymers from cornstarch for example) will increasingly
provide useful replacements for the main polymers of today.

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