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Polyethene,abbreviated PE, is one of the most important plastics. It is expensive, compared to PVC, but a very useful material nonetheless, because unlike PVC, it can safely be used to package food. The insides of milk brick packs are lined with Polyethene, for example. Very resistant to all kinds of chemicals, which makes it important for chemistry equipment: unbreakable containers and isolation material.

Physical appearance: solid, white, waxlike and translucent.

Polyethene is a thermoplast, which means than when heated, it can be worked into any shape and left to cool, retaining it's new shape. This means it can be reshaped, unlike other plastics (duroplasts). PE becomes flexible at about 110 degrees celsius. Depending on density (degree of polymerization), it can be flexible, or very hard. Of all polymers it has the simplest molecular structure: it is a chain of carbon atoms with two hydrogen atoms connected to each carbon atom. It's molecular structure thus looks like this:

     H   H   H   H   H
     |   |   |   |   |
   - C - C - C - C - C - (and so on for a few thousand segments)
     |   |   |   |   |
     H   H   H   H   H

Using the standard way of describing polymers:

   __               __
   |                 |
   |      H   H      |
   |      |   |      |
   |    - C - C -    |
   |      |   |      |
   |      H   H      |
   |                 |
   |_               _| n

PE is polymerized Ethene (C2H4). Since it only consists of hydrogen and carbon, it safely turns to Carbon Dioxide (CO2) and Water (H2O) when burned. (Compare PVC)

It is also called polyethylene.

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