Summary
First commercially developed in the 1930's, the use of polythene has increased dramatically and, because plastic is an inherently very strong and durable material, it has traditionally been buried when it has completed its useful life. Some of this plastic resurfaces as an environmental hazard, either through littering our countryside and seas or through being eaten by animals to their detriment. There are also major and very obvious problems caused by plastics being improperly discarded as litter.
d2w™ technology is based on the use of an additive which is combined with any blend of polyethylene or polypropylene resins during the standard production process usually at a level between 1% and 3%. At such low levels of inclusion, the impact of the additive is therefore negligible and the finished product retains all the dynamic qualities of standard plastics including strength, clarity, sealability, permeability and print. There is also no change involved to the standard plastics manufacturing processes and no impact on line speeds either during manufacture or in use.
The degradation process commences with any combination of heat, light and stresses acting as catalysts and affecting the speed with which it progresses. Once the process is initiated it will continue even in a landfill, if the plastics are caught in the branches of a tree or in a fence, or if they are under water.
One of the unique aspects of the new d2w™ totally degradable material is the controllable nature of the degradation process. The timescale of degradation and its initiation can be controlled according to the planned use of the film. What this means in practice is that d2w™ totally degradable plastics will retain all their required properties for the planned useful life of the product and the effects of the degradation process will only become evident some time after that useful life is complete.
Degradable plastics can be recycled and will not harm the post-consumer plastics waste stream. Conversely, d2w™ additive can be added to recycled plastics and will cause them to become degradable!
d2w™ plastics can be engineered to start to degrade in as little as 60 days or as long as 5 - 6 years, depending on the requirements of the product. This is achieved by using different formulations of the additive and different inclusion rates depending on the particular product specification, geography of use, and application specific useful-life demands. The actual speed of degradation will, however, still be affected by the levels of heat, light and stress to which it is subjected. The compostable version of this technology is engineered to completely degrade between 60 to 90 days in an in-vessel commercial compost environment, where typically temperatures in excess of 70 degrees centigrade are maintained to ensure compliance with the Animal ByProducts Directive.
Totally degradable plastics will degrade harmlessly ultimately leaving only H2O, CO2 and biomass in negligible quantities. Tests have proven the materials to be safe for direct food contact and to have no harmful effect whatsoever when they ultimately degrade in or on the ground.