1. Polymer materials: general characteristics

It's important to understand the reasons behind the special mechanical properties of polymers, especially when compared with those of simple organic molecules.

To achieve this, we need to consider the macromolecular nature of these compounds, i.e. the fact that a single molecular unit brings together a large number of repeating constituent units, known as monomer units. In the case of homopolymers, monomer units are derived from a single type of monomer molecule through a process of polymerization. In the case of copolymers, the original monomer molecules are different.

Whereas simple organic molecules are generally made up of a few dozen atoms at most – as are monomer units –, polymers are macromolecules with a very large number of atoms (from a few thousand to infinity). The strength of such assemblies is due to the existence of highly...