A Solution To The Plastic Bag Issue? 

With growing concerns and pressures on supermarket and retailers by governments to act more responsibly with regards to environmentally visible items such as carriers bags, it is crucial that plastics do not become unjustifiably demonised by the media. In addition the war between retailers to be seen as ‘more green’ than the others has sent a disproportionate amount of environmental flack towards the plastics industry and in particular the carrier bag. The carrier bag is a useful scapegoat as an icon of a throwaway society, but in fact the opposite is true. Unlike most plastic packaging the carrier bag is reused in the home more often than not as a waste receptacle or a convenient way of collating and collecting rubbish – not single use after all.

The plastic used to manufacture carrier bags is actually derived from waste products from oil production ‘naphtha’ and whilst the world remains an oil economy there will always be naphtha produced. It seems inexcusable not to use this resource and just flare it off at the drilling platform or the refinery, especially when it out performs so many alternative materials such as paper and biopolymer when comparing carbon footprints.

The majority of these carrier bags have reduced in thickness as advances in manufacturing and materials have been made and as a result a highly efficient bag has been produced. In addition to this most carrier bags have a high level of recycled material included into them – in some cases over 80% - reducing further the environmental impact.

All in all the carrier bag is an extremely efficient way of safely carrying home produce and goods. Weighing in on average at about 10 grams, compare the plastic carrier bag to the non recyclable fuel you will have used in driving to the shop in the first place and confirm what an insignificant impact banning the carrier bag will have on the environment. However, it is not to say that the check-out bag is optimized and that there are no further advances to be made, on the contrary, with new material advances, new strengths and performances become possible even for a carrier bag.

One solution to the concerns of government and environmental pressure groups lies with the use of oxo-biodegradable technology and this has become more favorable and more widespread in its applications over recent years. Essentially you take a normal carrier bag and render it ultimately biodegradable.

Reverte is one such technology which utilizes a pro-degradant package which can be carefully controlled and tailored to the life span of the product such as carrier bags. This additive developed and produced by Wells Plastics is incorporated into the bag at manufacture and does not impact at all on the properties of the bag; it is just as strong with no colour change, no smell and food safe. The life span of the bag is calculated by the manufacturer and the specification for the additive is drawn up. The carrier bag then enters into the retail stream and is eventually dispensed at the supermarket.

The bag is used and reused as per the homeowner’s normal routine and then the bag is discarded or disposed of into the waste system. At this point, with a small exposure to outside natural light and/or warmth, the breakdown reaction commences.

Plastics such as polyethylene can be thought of as a bowl of spaghetti, with the spaghetti polymer chains moving and sliding as the plastic is flexed and stretched. This structure allows the product to have all the physical properties that we expect from plastics such as they can be heated and reformed into new shapes.

The incorporation of Reverte into the plastic bags means that after a certain ‘dwell time’, a time when no physical change occurs, the spaghetti begins to be chopped up. After this has occurred to a significant extent the plastic is no longer plastic, its long chains are gone and the bag loses its plastics characteristics. It quickly disintegrates and is no longer litter if it has been inappropriately discarded. It addition the volume of the plastic is reduced as it no longer has the strength to maintain its form and therefore a reduction in landfill can be achieved – another highly important aspect.

Now that the plastic is no longer plastic it is a much shorter chain and it behaves like lignaceous natural products such as straw, twigs and leaves which are susceptible to bio-digestion by bacteria and fungi which are ubiquitous within the disposal environment.

The net result is that you have taken your plastic check – out bag, you have carried your good home, you have reused the bag, you have discarded it and then it degrades in to the environment and becomes available for bio-digestion. Assuming good environmental conditions for the bacteria the plastic bag ultimately to nature as biomass, H2O (water) and CO2 (carbon dioxide).

In addition to this if the Reverte treated bag is put into the plastics recycling stream that’s fine too! It will go through the recycling process and make perfectly good check –out bags, garden furniture or whatever. Reverte is currently used all over the world in applications such as carrier bags, agricultural films, bubble wraps, food containers and trash bags.

Wells Plastics Limited is an independent specialist manufacturing company based in the UK focusing on providing technical solutions to the plastic processing industry worldwide. Our products can be found everywhere from contact lens cases to roofing membranes though to food bags. With over 20 years experience Wells supply a wide range if different additive products including Reverte (oxo-biodegradable products) and Bactiglas (antimicrobial products).