The molecules of the traditional polymers
consist of long chains of carbon and hydrogen atoms. Because of their size and
homogeneity they are a difficult target for the enzymes of the natural
microorganisms. During the process of productionunder this technology
a special additive D2W is added. During the aftermath process of
crown treatment, the hidden phase of decomposition is initiated.Chemical reactions occur, provoked by
the sun radiation as well as the temperature and mechanical fluctuations, in
which the molecules of the prodegradant, the polymer and the oxygen from the
air participate. The reaction could generally be described as follows:
This additive serves as catalyser of the polymer(PE,PP,PS) decomposition under the influence of oxygen,
ultraviolet sun rays, thermal and mechanical fluctuations.
During the period prior to decomposition, the
wraps keep their mechanical properties and recycle ability.
Decomposition has two phases:
- the polymer chains
get chopped into small pieces and
-the chopped chains
become attacked by fungi and bacteria which would decompose the remains by
emitting carbon dioxide and water.
The D2W® is completely safe for human health. It may be applied
to wraps which are in contact with food.
Significantly, d
2w
™ oxo-biodegradable plastics do not need
a highly-microbial environment to degrade – this will happen even if the
plastic is left in the open air or in the sea! For this reason in particular,
‘oxo-bio’ plastic is preferable to ‘hydro-degradable’ eg starch-based plastic,
which requires an active bio-environment before degradation will work.
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 By Products 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.