Oxo-Biodegradable Earth Caps

How It Works – Degradation of the Norland Earth-Cap

The formulation used in the Norland Earth-Cap, contains a proprietary mixture of:

• a pro-oxidant
• a photo-initiated initial degradation inhibition element
• a secondary bio-degradation initiator.

This unique formulation has been developed to give the plastic cap, an in-house storage shelf life of approximately 24 months. There is a further “dwell time”, of around 6 months after disposal. This is followed by a rapid breakdown of polymer properties resulting in acute embrittlement, after 36 months from disposal. The three stages of the cap breakdown are classified as follows:

1. Embrittlement – After the cap is used, and then disposed, the embrittlement process begins. This embrittlement is activated primarily by sunlight, and/or heat generated within a landfill. The embrittlement process is similar visually to that of a shattered windshield-where the plastic cap begins fragmenting into small pieces. Scientifically, the molecular weight of the polymer chain has been reduced, thus increasing the microbial accessibility, and eventual bio-digestion.
2. Micro-fragmentation – this is the further fragmentation of the embrittlement stage into smaller fragments, which then begins the bio-digestion. This micro-fragmentation of the polymer chain promotes the growth of microbial colonies to expedite the biodegradation.
3. Bio-digestion – Is the consumption of the micro-fragmentation pieces, by the microbial colonies, resulting in the Earth-Cap being ultimately consumed.