Module 2

Lesson 3.1 What is a Polymer?

Polymers are large molecules composed of many smaller repeating molecules, all linked together.

The small molecules that make up a polymer are called monomers. Various types of monomers have various functional groups.

The process of joining monomers together is called polymerization.

Learning Tip

Given a polymer, you need to be able to identify the monomer from which it was produced.

Example: Consider polystyrene, a polymer often used to make cups and containers.

Fig. 2 Polystyrene

In order to identify the monomer, look for the smallest repeating pattern:

Fig. 3 Identifying the monomer in polystyrene

Add a double bond to fulfill all bonding spots. The resulting monomer is shown below.

Fig. 4 Styrene monomer

Polymers are categorized into two major groups - addition polymers and condensation polymers.