What are Polymers?

A polymer is a substance made up of long, repeating chains of molecules.

The properties of a polymer also depend on it's molecules.

The properties of polymers depend on monomers they are made from and the conditions under which they are made. poly(ethene) can be made in low density and high density forms.

Polymer molecules are relatively big and heavy.

They melt at higher temperature than other smaller molecules.

Polymers are usually solid at room temperature.

One example of a polymer is poly(ethene). Poly(ethene) is made of carbon and hydrogen atoms

Poly(ethene) is a thermosoftening polymer. Thermosoftening polymers soften easily on heating.

Thermosetting polymers do not melt when heated. The polymer molecules are linked to each other by strong cross links.

One example of a polymer is poly(styrene).

Poly(styrene) is produced from small molecules called monomers.

Poly(chloroethene) is a polymer produced from crude oil. poly(chloroethene) is used for water pipes, because it is waterproof.

Some polymers are made through condensation polymerisation.

Example of a condensation polymer is nylon.

Natural polymers are derived from plants and animals.

DNA, starch and proteins are biological polymers.

Proteins are biological polymers made from amino acid monomers.

Note: Nucleotides are the monomers for DNA, glucose is the monomer for starch, and amino acids are the monomers for proteins.

Starch and cellulose are biological polymers made by plants.

Examples of natural polymers are wool, rubber, starch and silk.

Synthetic polymers are prepared by a chemical reaction.

Synthetic polymers are silicon, nylon, PVC.

Some polymers are described as smart polymers. A smart polymer can return to original shape when conditions change.

Most polymers are not biodegradable.

One properties of polymers is that they are unreactive. But this property makes it difficult to dispose of polymers.