An in-depth study of plastics waste bags was carried out by the Heidelberg's Institute for Energy and Environmental Research (IFEU) in Germany. It concludes that the traditional polyester resins are less damaging for the environment than the biodegradable versions currently available in Europe.

The study compared the environmental impact of four different types of bags. The bottom line result showed that in terms of having the least negative impact, the recycled polyester bag comes first, followed by the regular polyester bags. The worst performers were the petrochemical biodegradable and the renewably-sourced material based plastics bags.

The study looked at 20 and 120-litre plastics waste bags on the market in Germany and a 30-litre size popular in France, comparing both regular and recycled PE resins with commercially-available biodegradable alternatives including starch and PLA-based formulations.
According to the sudy, the environmental impact of each waste bag is dominated by the raw material production process, whereas the conversion to bags and the transport to point-of-sale have relatively minor contribution in most cases.
Consequently, the environmental impact of the bags depends on the thinness of the material used for the given bag. The thinner the product is, the lower the environmental impact of the product.

“Virgin PE and recycled PE score well in environmental terms because the resins enable high levels of down-gauging to be achieved. The study shows the 20 litre PE bags used in Europe have a typical gauge of around 12.5 microns compared to 15-25 microns for biodegradable types.
The goal of the study was to establish whether the proposed taxes or restrictions covering use of traditional plastics in waste bag applications in Germany and Europe could be justified from an ecological perspective. It said the findings “show that sanctioning of conventional plastics in the framework of legal measures is by no means justified.

Even though the study was done by analyzing certain data in the context of proposed legislation in Europe, the study has direct implications to the North American plastic industry. It will be interesting to see what is going to be the long term consensus in terms of the environmental impact of the proliferation of the biodegradable plastic materials.

Our mission, in the meantime, is to provide our customers with bag making machines and pouch bag machines that are versatile and have the flexibility, so they can be used for both PE and biodegradable bag manufacturing.

Source of the information and the excerpts was an article by Chris Smith | EUROPEAN PLASTICS NEWS | September 1, 2009