Connect with us

Hi, what are you looking for?

Tech & Science

Bacteria used to create renewable and ‘infinitely recyclable’ plastics

The process also emits lower levels of carbon dioxide compared with the conventional methods of creating plastics.

Texas bears brunt of US plastic pollution
Environmental activist Diane Wilson shows plastic pellets that pollute the Gulf coast of Texas - Copyright GETTY IMAGES NORTH AMERICA/AFP/File Angela WEISS
Environmental activist Diane Wilson shows plastic pellets that pollute the Gulf coast of Texas - Copyright GETTY IMAGES NORTH AMERICA/AFP/File Angela WEISS

What if bacteria could be used to create plastics that are recyclable? Providing a means to replace the finite and polluting plastics based on petrochemicals? This is a solution being offered by the Lawrence Berkeley National Laboratory in the U.S.

Around the world plastic waste is a problem, especially on seas and along beaches. Around 14 million tons of plastic end up in the ocean every year and the quantity found on beaches is of a similar proportion. Too often plastic waste found on beaches is burnt and this causes a new form of plastic waste called ‘plastiglomerate’.

This rock-like material is made up of natural components, such as coral fragments, held together by the melted and reconsolidated plastic. Such rocks pose an increased environmental risk to coastal ecosystems such as seagrass beds, mangroves or coral reefs. The melted plastic decomposes more quickly into microplastics and is also contaminated with organic pollutants.

With the new study, researchers successfully engineered microbes to make biological alternatives for the starting ingredients in an infinitely recyclable plastic known as poly(diketoenamine), or PDK.

Unlike traditional plastics, PDK can be repeatedly deconstructed into pristine building blocks and then formed into new products with no loss in quality.

To create PDK, the researchers used Escherichia coli to turn sugars from plants into the required starting materials: A molecule called triacetic acid lactone, or bioTAL (light yellow solid that is soluble in organic solvents). So far, this has led to PDK with an 80 percent bio-content. The researcher expect to be able to achieve 100 percent bio-content in recyclable plastics soon.

The process also emits lower levels of carbon dioxide compared with the conventional methods of creating plastics.

PDKs can be used for a variety of products, including adhesives, flexible items like computer cables or watch bands, and building materials. The materials are also robust; for example, incorporating the bioTAL into the material expanded its working temperature range by up to 60 degrees Celsius compared to the petrochemical version.

According to one of the lead researchers, Professor Jay Keasling: “We can’t keep using our dwindling supply of fossil fuels to feed this insatiable desire for plastics. We want to help solve the plastic waste problem by creating materials that are both biorenewable and circular — and providing an incentive for companies to use them. Then people could have the products they need for the time they need them, before those items are transformed into something new.”

The study was supported by the U.S. Department of Energy’s Bioenergy Technologies Office and the study appears in the journal Nature Sustainability, titled “ Biorenewable and circular polydiketoenamine plastics”.

Avatar photo
Written By

Dr. Tim Sandle is Digital Journal's Editor-at-Large for science news. Tim specializes in science, technology, environmental, business, and health journalism. He is additionally a practising microbiologist; and an author. He is also interested in history, politics and current affairs.

You may also like:

Tech & Science

The Tesla Cybertruck is the most searched-for future electric vehicle in the UK.

Business

Tax cuts will have no impact whatsoever.  

Business

"Today's Gaza journalists have long known that their 'press' vests do not protect them," he wrote..

Business

Asian equities edged higher Tuesday after recent losses as investors ignored another tough day for tech titans on Wall Street.