Polymerization is one of the most important concepts in IB Chemistry. It explains how small molecules (monomers) join together to form giant molecules (polymers) with unique physical and chemical properties. From plastics to proteins to DNA, polymerization is everywhere. Understanding how polymerization works is essential for analyzing materials, predicting products, and interpreting organic reactions on exams.
What Is Polymerization?
Polymerization is the chemical process in which small molecules called monomers join together to form long chains called polymers.
Key characteristics:
- Monomers are repeat units.
- Polymers are large molecules made of hundreds or thousands of monomers.
- Polymers have different properties from the monomers that form them.
Polymers may be natural (like proteins or cellulose) or synthetic (like nylon or polyethylene).
Types of Polymerization
IB Chemistry requires you to know two main types of polymerization:
- Addition Polymerization
- Condensation Polymerization
These differ in mechanism, monomers, and products.
1. Addition Polymerization
Addition polymerization occurs when alkene monomers join together by breaking their C=C double bonds.
Key features:
- Only one type of monomer is needed.
- Double bond opens to form single bonds.
- No by-products are formed.
This process produces many common plastics.
