Technology for biodegradable plastic bag developed at PE centre

A TEAM of Port Elizabeth scientists broke new ground recently when they developed 100% biodegradable plastic bags made from agricultural by-products.

This means South Africans will soon be able to dispose of their plastic bags along with the rest of their waste without having to worry about any possible negative effects on the environment.

The team, from the Council for Scientific and Industrial Research (CSIR) Polymer and Composite Research Group in Port Elizabeth, developed the maize and sugar cane bio-based bags which are completely biodegradable in mud‚ soil‚ water and compost.

They break down completely in just three to six months.

The bags can also be recycled and major retailers like Woolworths and Pick n Pay are already in line to test the product in a pilot phase.

CSIR senior researcher Sudhakar Muniyasamy‚ who led the team that made the discovery‚ said yesterday that the new bags had the same durability as normal plastic bags but many more advantages.

“These biodegradable plastic bags can improve market opportunities and end-user industry, and reduce the amount of plastic waste in South Africa‚” Muniyasamy said.

“The technology is mainly designed to meet physical-chemical properties but when disposed in natural environments it undergoes biodegradation in landfill‚ compost and marine water by process of natural micro-organisms in a timely and efficient manner.”

In South Africa, about 90% of current conventional plastics bags are made from petroleum-based chemical materials and are not biodegradable in natural environments.

Muniyasamy said the new bags cost two to three times more to manufacture than normal bags‚ but that costs would come down once production was scaled up.

“We hope that by September we will be able to give them some pilot samples to try out and we expect to be in the commercial stage by early next year.” Plastics SA sustainability manager Jacques Lightfoot believes the new bags will be good for the environment, but has concerns over its effect on existing industry jobs.

“The problem for us is that the normal bags are also being recycled, so if the new bags are not marked correctly they will contaminate normal bags if they are stored together.”