Polymer backbones

PlasticsPolymer backbones

Plastics are widely used as they have many useful properties. Most plastics and synthetic fibres are made from chemicals derived from crude oil and are made up of long chain molecules called polymers.

The 'backbone' of a polymer can tell us whether it is an addition polymer or a condensation polymer. Only addition polymers are covered in the National 5 course.

A horizontal chain can be seen in the polymer below (poly(ethenol)):

A chain of six carbon atoms. The first, third and fifth carbons are bonded to two hydrogens. The second, fourth and sixth carbons are bonded to a hydrogen and a hydroxyl group.

This polymer only has carbon atoms in it's backbone. This indicates that the molecule was formed by addition polymerisation.

Natural polymers

Polymerisation

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PlasticsPolymer backbones