The majority of plastics today are created from oil, which is unsustainable. This can change though. Scientists from the Centre for Sustainable Chemical Technologies ( CSCT ) at the University of Bath ( UK ) have developed a renewable plastic from a chemical known as pinene which is present in pine needles.

Pinene is the aromatic chemical from the terpene family that gives pine trees their distinctive “Christmas smell” and is also waste by-product of the paper industry.

The researchers hope the plastic might be utilized in a variety of applications, including plastic bags, food packaging and even medical and surgical implants.

Renewable plastics from trees

Degradable polyesters such as PLA (polylactic acid) are produced from crops such as sugar cane or corn, however PLA can be mixed with a rubbery polymer known as caprolactone to make it more flexible. The problem is, caprolactone is produced from crude oil, and so the resulting plastic is not completely renewable.

The scientists published their results in the journal Polymer Chemistry (pdf). They used pinene as the raw material to make a this new type of plastic that can be used in place of caprolactone.

Helena Quilter, a PhD scholar at the CSCT , elaborated:

“We are not talking about recycling old Christmas trees into plastics, but rather utilizing a waste product from an industry that would otherwise be thrown away, and turning it into something useful. So if we are able to make plastic from sustainable sources, it might make an enormous difference to the environment.”

Replacing fossil fuels

Professor Matthew Davidson, who established the CSCT at Bath in 2008 and is currently the Director of its Engineering and Physical Sciences Research Council’s ( EPSRC ) Centre for Doctoral Training (CDT) says: “This research is part of a wider project that aims at using bio-based chemical substances like pinene as a sustainable starting material for making a variety of useful products in place of petrochemicals. This reduces our reliance on fossil fuels and offers a renewable feed-stock that has the potential to revolutionize the chemical trade.”

The EPSRC has been funding the research, which is also investigating using other terpenes, such as limonene from citrus fruit, as an alternative to petrochemicals to make a range of products from plastics to pharmaceuticals.

The research is still it the early phase – so far just a few grams have been made – however the scientists’ goal is to scale up the method to produce bigger quantities in the coming future.

Terpenes: chemicals that may change the chemical industry