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Degradable Vs Oxo-Biodegradable
Degradable plastics
use heat, sunlight or moisture (and/or enzymes) to weaken the
polymer chains. This results in a breakdown of the plastic into
smaller fragments. The smaller residues remain after the degradation
is complete.
Oxo-Biodegradable
plastics have the addition of a specially formulated additive
which involve micro-organisms that consume the degraded plastic
as a source of food and energy. The end result enhances the environment
by producing a biomass that can be absorbed into the soil
Oxo Biodegradable - The Science
BCW’s biodegradable range of products use a specially designed
additive that enable the biodegradable process. They contain a
metal ion pro-degradant to impart a photo-degradable and thermal-degradable
property to polymers In addition, it contains a unique secondary
stage biodegradation promoter. This controls the timing and triggering
of the oxo-biodegradation. This additive has been approved for
food usage.
Oxo-biodegradable is the term used to describe biodegradation
of standard polyolefins via an oxidation route. The high molecular
weight of commercial grades of polymers render them too hydrophobic,
therefore resistant to direct microbial attack. Oxo-biodegradation
involves the small addition of a masterbatch (1-5%) to a standard
polyolefin such as Polypropylene (PP) or Polyethylene (PE) to
produce a biodegradation. The addition of the masterbatch at the
correct level will result in total biodegradation of the polymer.
The molecular weight (mw) of the polyolefin is repeatedly reduced
by chain scission (the breaking of a molecular bond causing the
shortening of the overall chain) A 2 Stage Process: i) converted
by reaction with oxygen to molecular fragments that are water-wettable
ii) the smaller oxidized molecules are biodegraded and converted
to carbon dioxide ( CO2 ), water ( H2 ) and biomass by micro organisms.
The polymer is totally biodegraded into the environment
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