3      How does it works ?

The degradation process is initiated at the time the polyethylene or polypropylene is extruded by the inclusion of a small amount of a special additive. This additive works to break down the carbon-carbon bonds in the plastic leading to a lowering of the molecular weight and eventually to a loss of strength and other properties. Stabilisers work to ensure that a sufficiently long useful life is provided for each specific application. For example, a refuse sack might require a useful life of say 18 months before beginning to lose its strength whereas a bread bag might only require a few weeks.