Plastic is one of the most common materials in everyday life. From disposable packaging to display cases that show off our most valuable assets, plastic has an almost infinite range of uses. But what exactly is plastic composed of?

Scientifically speaking, all varieties of plastic are polymers. Modern plastics companies almost exclusively use synthetic polymers these days, although organic polymers also exist and were important in the early days of plastic’s history. A polymer is essentially a molecule in the form of a long chain, made up of smaller building blocks that are referred to as monomers. A polymer that is formed of only one type of monomer is referred to as a homopolymer. Polyethylene and PVC (polyvinyl chloride) are two very common types of homopolymers.

Plastics are not the only type of polymer that we use. Rubbers (often referred to as elastomers in today’s market) are also considered polymers.