Where Does Plastic Come From?

A smattering of applications made possible with plastics.

Imagine a world without plastic. No water bottles, no sleek smartphone casings, no corrugated plastic lawn signs, no vinyl Beatles albums, no toothbrushes. It’s hard to picture, isn’t it? Plastics are everywhere, woven into the fabric of our daily lives. (In fact, much of the fabric we wear is plastic--polyester or nylon.) But have you ever stopped to wonder: where does this stuff come from? Its origin is fossil fuels. Even the giant banners that protesters carry to protest against the oil industry were made with synthesized oil.

The journey of plastic, from raw materials to the products we use, is an interesting blend of chemistry, industry, and innovation. 

Here's the backstory of where plastics originate and how they come to be.

The Fossil Fuel Foundation

The vast majority of plastics—over 99%—originate deep underground. That is, most plastics are born from petroleum and natural gas, the fossil fuels that have powered much of modern industry. These resources are like the raw canvas for plastic production, rich in hydrocarbons that form the building blocks used in many of our favorite materials.

The process begins with refining, where crude oil or natural gas is distilled in massive industrial facilities to separate out valuable components. From crude oil, we get naphtha, and from natural gas, we extract ethane. These hydrocarbons are the stars of the show, but they need some transformation to become plastic. 

This is where cracking comes in, a process that breaks these hydrocarbons down into smaller, more manageable molecules called monomers, like ethylene and propylene. Think of monomers as Lego bricks—small, simple units that can be snapped together to create something bigger.

Next comes polymerization, where these monomers are chemically bonded into long chains called polymers. My father was a chemist whose career revolved around polymers, primarily in the real of house paints and adhesives. Before the development of latex paints, homes were painted (inside and out) with lead-based paints. We've since learned that lead is a toxic chemical that can cause brain damage, especially in children.  

Through polymerization, those chains become the plastics we know, like polyethylene (think plastic bags and bottles) or polypropylene (used in food containers and packaging). To give plastics their unique traits—flexibility, durability, or color—manufacturers mix in additives like stabilizers, colorants, or plasticizers. It’s like seasoning a dish to get just the right flavor.

Bio-Based Plastics

Not all plastics come from fossil fuels, though. A small but growing fraction—about 1% of global production—is plant based. Plastics like polylactic acid (PLA) are made from renewable sources such as corn starch, sugarcane, or other plant materials. The process involves fermenting these plants to produce lactic acid, which is then polymerized into plastic. It’s a bit like brewing beer, but instead of a cold pint, you get a biodegradable coffee cup.

These bio-based plastics are gaining traction as the world grapples with environmental concerns, though producing them still requires energy and land.

Recycling Plastics

Used plastics—like the water bottle you tossed in that bin—can be collected, cleaned, and reprocessed into new products. The idea of it sounds good, but only about 9% of plastic waste globally is actually recycled. The rest ends up in landfills, incinerators, or our oceans. I'm often surprised when I learn that there are many parts of this country that have no recycle centers. According to National Geographic, less than 10% recycle their plastic waste. And some sources say it's half that number.

Recycling plastics is tricky. The process can be costly and energy-intensive. Then again, if some folks had their way and they succeeded in bankrupting all the companies involved in oil production, we won't have to worry about how to recycle or safely discard our plastics. There won't be any.