• There are various items around us that are made up of polymers such as protein, starch, polyethylene and nylon.
• The basic unit of a polymer is called a monomer.
• The reaction of monomer fusion to produce a polymer is called the polymerisation reaction.
• Polymers can be classified into several groups based on the source of the polymer, the way the polymer is produced and the characteristics of the resulting polymer.

Polymer Sources

• Polymers consist of natural polymers or synthetic polymers.
• Natural polymers are polymers that are produced naturally and can be obtained from the environment.
• Examples of natural polymers include starch, protein and cotton.
• Synthetic polymers are produced by humans through chemical reactions in laboratories or in factories.
• Nylon, polyethylene, polystyrene and polyvinyl chloride (PVC) are among the examples of synthetic polymers produced in the industrial sector.
• Starch is a natural polymer made from glucose.
• Meat is one of the sources of protein. Proteins are made from amino acids that are a type of monomer.

Types of Polymers

Polymerisation Reactions

• Polymerisation reactions are divided into two types, namely addition polymerisation and condensation polymerisation.
• Addition polymerisation occurs when the monomer has a double covalent bond between the carbons, C = C reacting with each other.

• During the reaction, double bonds are "opened" and monomers are "added" to the molecular chain to produce a polymer.
• The following diagram shows the polymerisation of ethene to produce polyethene.

• Condensation polymerisation involves at least two different types of monomers.
• The monomers involved have two functional groups involved in the polymerization reaction.
• The result of condensation polymerization is a polymer and another product such as water or HCl molecules.

Use of Polymers in Everyday Life

• Features not found in natural polymers include:

Uses of Synthetic Polymers

• Various medical and laboratory devices are made from polypropene.
• The most widespread use of polyethylene is as a plastic bag.
• Nylon produces yarn that is important for the textile industry.
• Acrylic polymer coatings are used to produce waterproof roofs.

Polymers and the Environment

• The nature of some polymers which are durable and take a very long time to decompose causes serious pollution problems.
• Pollution in the oceans causes many living things to die and microplastics to enter the food chain.
• Garbage disposal centers are filled with non-biodegradable plastic bags that will affect the environment.
• Recycling is the easiest way for consumers to ensure synthetic polymers do not end up in landfills.
• The introduction of degradable or decomposable polymers especially for plastic products allows pollution to be reduced.
• Additives are included to allow plastic items to decompose naturally by bacteria (biodegradation) or decompose by light (photodegradation).
• Plastic items will decompose faster and can reduce the problem of dumping plastic items at landfills as well as safer for wild animals.