Definition of polymers and plastics: 

Polymers are chemical compounds in which molecules are bonded together in long, repeating chains. Plastics are a specific type of polymer comprised of a long chain of polymers. 

What are polymers?

Polymers are a class of natural or synthetic substances composed of very large molecules, known as macromolecules. These macromolecules are multiples of simpler chemical units called monomers. The process by which monomers link together into a polymer chain is known as polymerisation. 

Naturally occurring polymers are widespread, with examples including silk, wool, DNA, cellulose, and proteins. It is also possible to create polymers synthetically from oil, petroleum, or bio-based sources. Examples of synthetic polymers include nylon, polyethylene, polyester, Teflon and epoxy. 

What are plastics?

Plastics are a specific type of synthetic or semi-synthetic polymer. They are made from molecules derived from oil, petroleum, or bio-based sources, which are combined to create different polymers. Plastics are known for their ability to be molded, extruded, or pressed into solid objects of various shapes. 

There are seven main types of plastic, each suited to certain applications. The three most common types are: polyethylene (PE), which is used to make products like shopping bags, cling film, and hydraulic seals; polypropylene (PP), which can be found in laboratory equipment, automotive parts, and medical devices; and polyvinyl chloride (PVC), a common feature in a wide variety of construction materials. Other types of plastics have applications including glass alternatives, food containers, luggage, protective headgear, and refrigeration devices.  

Why are polymers and plastics important?

Naturally-occurring polymers include proteins and DNA, the building blocks of life on Earth. Other natural polymers, such as wool, have played a significant role in human societies for centuries. 

More recently, synthetic polymers have become an integral part of the global economy, valued for their immense versatility and low production costs. For example, between 1950 and 2015, 8.3 billion tons of plastic were produced – equivalent to more than 1,000 kilos per head of the world’s present population – of which 50% was manufactured after 2004.

What are the challenges associated with polymers and plastics?

Synthetic polymers present a significant environmental challenge for two main reasons. The first is that their current production is mostly reliant on petrochemical products, the use of which contributes to rising global temperatures. The second challenge is disposal. Due to their slow biodegradability, synthetic polymers (mostly plastics) often cause environmental deterioration after disposal, which can harm ecosystems and threaten the global food chain. Solving this twofold issue depends on finding more responsible ways of producing and disposing of synthetic polymers. 

What is the future of polymers and plastics?

The latest developments in polymer and plastic technology focus on reducing the planetary impact of synthetic polymers. Bio-based polymers, for instance, are produced from renewable feedstocks and can also be biodegradable. The market for these products is expected to reach USD 29.7 billion by 2026. With further innovations in this field, bio-based polymers will become more widespread in medicine, industry, agriculture, and beyond. Learn more about CHAMPION a project for bio-based polymer alternatives.

At the same time, efforts are underway to tackle the problem of plastic waste in marine ecosystems. The Ocean Cleanup®, a non-profit that develops and scales technologies to rid the ocean of plastic waste, is a notable example. The organisation engages individuals, corporations, and governments with the target of reducing 90% of floating ocean plastic, and its new System 03 technology is expected to capture plastic 10 times faster than the previous version.