Monomers, Polymers, and Plastic

All plastics contain polymers, but not all polymers are plastic. Confused yet? Let’s break this down. Monomer means “one,” and monomers are small molecules containing one part. These molecules can join with other molecules to make a whole chain – a polymer.

There are plenty of monomers and polymers in nature. Your DNA, for instance, is one long polymer. Think of a monomer as a paper clip – there’s just one. But what if you attached a bunch of paper clips together? Now you have a polymer. Polymers found in nature include things like leather, silk, wood, wool and cotton.

Plastic is a polymer made by humans in a lab or factory. It’s usually made from the carbon in oil or natural gas, but it can be made from other natural products like wood fibers or banana peels!

Fun Facts

  • Plastics are usually made with high pressure and high heat.
  • Some plastics, thermoplastics, are easy to recycle because they melt under high heat. Thermoset plastics are harder to recycle because they don’t melt.


Monomer: One

Polymer: a substance containing different types of molecules

Synthetic: made by man

Plastic: a synthetic polymer

Learn More

Make a polymer at home with homemade silly putty at PBS Kids.

Q and A

Question: Can’t we just use natural products? Why do plastics matter?

Answer: Plastics are more lightweight and less expensive to produce than items made from glass or wood. They’re easy to clean and they’re pliable so they can be used for many things, such as medical tubing, toys, or even the insides of cars.