How the Eco Poly Jacket degrades
The newly developed film includes an additive which is added at the beginning of the extrusion process to reduce the molecular weight of the polythene without affecting its performance.
The additive can reduce the molecular weight from 300,000 to 4,000, at which point it can be consumed by micro organisms found everywhere. The process can be carefully controlled to programme the life of the film, according to its intended use.
In time, the film will begin to degrade in any normal environment, a process enhanced by daylight or higher temperatures. It does not need a microbial agent to initiate degradation and, in fact, degrades more readily than paper. The eventual products of degradation are water, a small amount of carbon dioxide and biomass which can be composted and used as a fertilizer.
Click the picture for a larger image
The degradability has been measured against conventional polythene film using a series of tests which accelerate the ageing process. The tests prove that UV light, heat and moisture in normal cycles will cause the material to degrade. Chemical analysis shows that this is due to change in chemical composition with the reduction in molecular weight.
The degraded product has passed the standard range of ecotoxicity tests, such as seed germination, plant growth and the survival of daphnia and earthworms.
The new Eco Poly Jacket can also be sent for recycling in the usual way along with other polythene. In fact, the degradable polythene film can also be made from recycled polythene. Thus this new envelope fits either of the desired cycles: continued use as a plastic or return to biomass, as shown in the diagram.