The big problem with plastics is that though they last for a very long time, most are thrown 

away after only one use. Since plastics were invented in the 1950s, about 8,300m metric 

tonnes (Mt) have been made, but over half (4,900 Mt) is already in landfill or has been lost to 

the environment. In 2010 alone, an estimated 4.8 to 12.7 Mt went into the oceans.

Only a small proportion of the hundreds of types of plastics can be recycled by conventional 

technology. But there are other things we can do to reuse plastics after they've served their 

original purpose. My research, for example, focuses on chemical recycling, and I've been 

looking into how food packaging can be used to create new materials like wires for electricity.

In chemical recycling you use the constituent elements to make new materials. All plastics are 

made of carbon, hydrogen and sometimes oxygen. The amounts and arrangements of these 

three elements make each plastic unique. As plastics are very pure and highly refined 

chemicals, they can be broken down into these elements and then bonded in different 

arrangements to make high value materials such as carbon nanotubes. In theory, the only side 

products from doing this should be oxygen and hydrogen.

Carbon nanotubes are tiny molecules with incredible physical properties. Think of a piece of 

chicken wire wrapped into a cylinder. This is what the structure of a carbon nanotube looks 

like. When carbon is arranged like this it can conduct both heat and electricity. These two 

different forms of energy are each very important to control and use in the right quantities, 

depending on your needs.

For our new study, we took plastics—in particular black plastics, which are commonly used as 

packaging for ready meals and fruit and vegetables in supermarkets, but can't be easily 

recycled – and stripped the carbon from them, then built nanotube molecules from the bottom 

up using the carbon atoms.