Driving along our 21st century motorways, we often notice rubbish that accumulates alongside roads, spoiling the nice scenery. A closer inspection of that flittering garbage reveals that it is mainly plastics. Cast away after only a short usage time, we have to ask ourselves whether we will ever be able to get rid of our plastic mess.

Did You Know?
Plastics are a huge environmental issue. Some cities are considering charging up to 5¢ per grocery bag to encourage consumers not to use them.

To be able to answer that fully, we shall first get some knowledge about the stuff that we are talking about. Plastics, or better polymers, shall in no way be condemned. They provide light weight, cheap-and-easy packaging, along with good stability. Their versatility is shown in the large variety of plastic products, ranging from very thin clinging wraps to stable furniture.

Standard polymers, like shopping bags, are chemically stable and do not rot over time. This is, of course, advantageous when considering packaging that is meant to provide protection for the products stored on the inside, rather than decompose before the products do themselves.

This stability that makes plastic such a good packaging product, however, is also the material's tragic flaw. This downside reveals itself only after plastics have been chucked or "accidentally" dropped.

Currently, every plastic bag that we carry out of our supermarkets will ultimately lie around somewhere in a landfill, where it will stay virtually unchanged for at least the next century. On the other hand, recycling polymers is costly and requires so much energy that it becomes more environmentally friendly to burn the stuff in a waste incineration plant and convert the produced heat into energy instead.

Did You Know?
It can take more than a century for plastics to degrade!

But wouldn't it be nice if these plastic products would just decompose in a similar way as biological waste? Just imagine... rubbish polluting our motorways would vanish within less than a month. It would be a wonderful thing.

Scientists have tried for a long time to use a natural mechanism to help in the process of biological litter destruction, i.e. the best waste control mechanism ever developed: Bacteria.

Until recently, these micro-organisms that usually take care of the recycling of all organic matter, from leaves to carrion, failed to digest polymers due to plastics' complex chemical structure. However, developments furthered by a research group from the chemical global player BASF have resulted in a polymer that is in fact completely biodegradable. These particular polymers can, in principle, be included with the other biological waste so that both polymers and organics can decay together.

There have been cases in which conventional polymers have been partly decomposed, but the result of breaking down the chemical structure resulted in substances that were in some way detrimental for humans or nature. But not so for the "wonder-polymer" designed in the BASF laboratories, sold under the name Ecoflex.

Did You Know?
Scientists are working on "biodegradable" plastics to help reduce landfills.

It was shown by the research team, headed by Rolf-Joachim Mueller and Uwe Witt, from Braunschweig University in Germany that Ecoflex can completely decompose after just three weeks under simulated compost conditions of 55°C and with the help of certain bacteria that are always present in any garden compost. And best of all, there were no traces of environmentally unfriendly chemical residues.

Dirk Staerke, the managing marketing director for Ecoflex at BASF headquarters, stated that Ecoflex is currently produced at a rate of 8,000 tons per year. And this is just the beginning. The costs of research and development still have to be covered, but in the foreseeable future we will start discovering the biodegradability label on our regular shopping trips without having to pay an additional penny just for the wrapping.

If we open our eyes a bit further on the world market we will see that there are many other plastics that strive for the same properties and that offer reasonably fast degradability. All these developments help reducing the negative impacts humans nowadays have on our environment. However, before we can actually start indulging in exultation we still have to consider that all these polymers have to be produced n the first place.

Did You Know?
Reducing waste, for example by taking fabric bags to the supermarket, is the best way to save raw materials and much energy.

...Just imagine landfill sites converting themselves into something resembling a gigantic garden within less than a month. Such are the developments that give us hope that we can enjoy our plastic future with fewer worries to take care off. And considering the huge amount of rubbish we tend to produce these days, science is up to providing useful solutions — for the sake of nature, ourselves, and especially the next generations that will have to deal with the consequences of the thoughtless mess we leave behind.

References

U. Witt, T. Einig, M. Yamamoto, I. Kleeberg, W.D. Deckwer, R.J. Mueller (2001): Biodegradation of aliphatic-aromatic copolyesters: evaluation of the final biodegradability and ecotoxicological impact of degradation intermediates, Chemosphere, Vol. 44, 2001, p. 289-299.

Interview with R.-J. Mueller, German Research Centre for Biotechnology, Braunschweig, Germany.

Interview with D. Staerke, BASF, Ludwigshafen, Germany.

http://www2.basf.de/basf2/html/plastics/englisch/pages/biokstoff/ecoflex.htm

Article first published on June 14, 2007.

Lars Rose

Lars Rose is a PhD candidate in high temperature Solid Oxide Fuel Cell research (that is sustainable energies), at the Department of Materials Engineering in the Faculty of Applied Science at the University of British Columbia (UBC), and at the National Research Council Canada, Institute for Fuel Cell Innovation (NRC-IFCI). He enjoys teaching fun stuff and is the current Media Relations and Human Resources coordinator of the outreach program Let's Talk Science at UBC. He enjoys writing science in a fun way for CurioCity, UBC Terry, the Science Creative Quarterly, Fuel Cell Today and Ubyssey.



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