Scientists develop way to make biodegradable plastic cheaper


A way of producing biodegradable plastic cheaper that could lead to it becoming more widespread.

Scientists at the KU Leuven Centre for Surface Chemistry and Cataysis have produced a new method to create the bioplastic known as polylactic acid (PLA).


PLA is derived from renewable sources such as the sugar in maize and sugarcane.

Fermentation turns the sugar into lactic acid, which in turn is a building block for PLA.

In certain environments, PLA degrades after a number of years, but if it is collected and sorted correctly, it is both industrially compostable and recyclable.

But PLA has not become an alternative to traditional petroleum-based plastics due to its cost.

KU Leuven Professor Bert Sels said: “First, lactic acid is fed into a reactor and converted into a type of pre-plastic under high temperature and in a vacuum.

“This is an expensive process. The pre-plastic – a low quality plastic – is then broken down into building blocks for PLA.

 “In other words, you are first producing an inferior plastic before you end up with a high-quality plastic. And even though PLA is considered a green plastic, the various intermediary steps in the production process still require metals and produce waste.”

The scientists have developed a new technique use a porous material known as a zeolite as a catalyst in the process. This process converts lactic acid directly into the building blocks for PLA without making the larger by-products.

This means the process is cheaper, there is less waste, and metals do not need to be used.

A chemical company has already bought the patent on the process and intends to roll out production on an industrial scale.

The findings were first published in the journal Science.