Polymer: Definition, Types, Examples, and Uses in Chemistry

Polymer is essential in chemistry and helps students understand various practical and theoretical applications related to this topic.

What is Polymer in Chemistry?

A polymer refers to a large molecule made up of repeating subunits known as monomers. This concept appears in chapters related to organic chemistry, biochemistry, and materials science, making it a foundational part of your chemistry syllabus.

Molecular Formula and Composition

The molecular formula of a polymer depends on its repeating unit or monomer. For example, polythene (polyethylene) has the repeating unit –(C₂H₄)–_n. It consists of carbon and hydrogen atoms and is categorized under high-molecular-weight macromolecules.

Preparation and Synthesis Methods

Polymers can be prepared by two main methods: addition (chain-growth) polymerization and condensation (step-growth) polymerization. In addition polymerization, unsaturated monomers like ethene form long chains (e.g., polythene). 

In condensation polymerization, two different monomers react and eliminate small molecules like water (e.g., nylon-6,6, which forms from hexamethylenediamine and adipic acid).

Physical Properties of Polymer

Physical properties of polymers depend on their structure and types. Most polymers are lightweight, flexible, and insulators of heat and electricity. 

Some can be hard and rigid (e.g., Bakelite), while others are elastic (e.g., rubber). Their melting points, solubility, and appearance change with their structure.

Chemical Properties and Reactions

Polymers show resistance to acids and bases, but some can undergo hydrolysis or oxidation. Crosslinked polymers like Bakelite do not melt on heating, while thermoplastics like polythene can be softened. Polymers can react with UV light (causing degradation) and certain solvents.

Frequent Related Errors

• Thinking all polymers are synthetic plastics and forgetting about natural polymers like protein or cellulose.
• Confusing addition and condensation polymerization steps.
• Mixing up thermoplastic and thermosetting polymers.
• Not recognizing copolymers (made from two or more different monomers).

Uses of Polymer in Real Life

Polymers are widely used in packaging (like polythene bags), textiles (nylon, polyester), toys, utensils, automotive parts, and electronics. Natural polymers, such as cellulose, are used in paper, and proteins are essential for body function. Biodegradable polymers are gaining popularity for eco-friendly packaging.

Relation with Other Chemistry Concepts

Polymer chemistry is closely related to organic chemistry and biochemistry. It helps understand the structure of macromolecules like DNA and proteins. Topics like polymerization and types of thermoplastics and thermosetting polymers make the study of polymers practical and interconnected.

Step-by-Step Reaction Example

1. Start with the monomer ethene (C₂H₄) for polythene synthesis.

2. Under high pressure and with a catalyst (conditions), the double bond breaks and the ethene molecules join to form long chains:

3. The result is a solid, flexible material used for packaging.

Lab or Experimental Tips

Remember polymers by associating them with repeated building blocks—like beads on a string. Visualizing the structure helps prevent confusion with simple molecules. Vedantu educators often use models or animations to make this topic easier to understand.

Try This Yourself

• Identify whether rubber is a natural or synthetic polymer and name its monomer.
• Give two uses of nylon in daily life.
• Write the IUPAC name for the polymer formed from vinyl chloride.
• Classify Bakelite as thermoplastic or thermosetting and state its application.

Final Wrap-Up

We explored polymers—their structure, types, synthesis, and uses. Understanding polymers builds a strong foundation for learning about materials, biology, and environmental science. For more topics like this, explore interactive study tools and live classes on Vedantu.