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Question : Does d2w™ comply with degradable standards?
Answer :
d2w Certification/Standards
* New draft British Standard BS 8472
(In final stages of creation at British Standards Institute)
* ASTM (US) 6954 testing protocol
* New French Standard AFNOR54-980
* Food Contact Safe – tested by RAPRA, UK
* Soil Safe – tested by OWS, Belgium
* Biodegradable – tested by PYXIS, UK
* SGS-Food Contact Safe
(1) CEN
Oxo-degradation of plastics is defined by TC249/WG9 of CEN (the European Standards Organisation) as "degradation identified as resulting from oxidative cleavage of macromolecules." And oxo-biodegradation as "degradation identified as resulting from oxidative and cell-mediated phenomena, either simultaneously or successively."
(2) BRITISH STANDARD (BS 8472)
A draft standard capable of measuring oxo-biodegradation has also been published by the British Standards Institution in 2007.
BS 8472 (Draft) Packaging – Method for determining the degradability, biodegradability and non-eco-toxicity of oxo-biodegradable plastics
This draft British Standard is based on the same testing procedures as D 6954. It does
not mandate abiotic degradation within a specific time-frame because the loss of
mechanical properties relates to the use to which the plastic is put, and is a matter for
agreement between the manufacturer and user. The biometric and eco-toxicity
requirements are similar.
(3) ASTM D 6954
The American Society for Testing and Materials (ASTM International) acknowledges the oxo-biodegradable technology in ASTM D 6954–04. This is a standard guide specifically developed for plastics that degrade initially by an oxidative process and subsequently biodegrade. D 6954 prescribes the tests to be done in order to rate these materials in terms of their ability to degrade, biodegrade and to assess their eco-toxicity impact to the environment of disposal.
The ASTM6954 guide provides a framework or a road map to compare and rank the controlled laboratory rate and degree of physical property losses of polymers by thermal and photo oxidation processes and biodegradation, and ecological impacts after degradation in defined applications and disposal environments. Disposal environments range from exposure in soil, landfill, and compost where thermal oxidation may occur, and to land cover and agricultural use where photo-oxidation may also occur.
This standard guide uses established ASTM standards in three tiers
Tier 1 for accelerating and measuring the loss in properties and molecular weight by both thermal and photo-oxidation processes, and other abiotic processes;
Tier2 for measuring biodegradation;
Tier3 to assess ecological impact of the products from these processes;
The Tier 1 conditions selected for thermal oxidation accelerate the degradation likely to occur in a chosen application and disposal environment. The conditions should include a range of humidity or water concentrations based on the application and disposal environment in mind. The measured rate of degradation at typical oxidation temperatures is required in order to compare and rank the polymers being evaluated in that chosen application to reach a molecular weight that constitutes a demonstrable.
biodegradable residue (using standard ASTM biometer tests for CO2 evolution appropriate to the chosen environment). By way of example, accelerated oxidation data must be obtained at temperatures and humidity ranges typical in that chosen application and disposal environment, e.g. in soil (20C to 30C), landfill, 20C to 35C) and composting facilities (30C to 65C). For applications in soils, local temperatures and humidity ranges must be considered as they vary widely with geography. At least one temperature must be reasonably close to the end use temperature, but under no circumstances should this be more than 20C. It must, also, be established that the polymer does not undergo a phase change, such as glass transition temperature (Tg).
The residues resulting from the oxidations are then exposed to appropriate disposal or use environments in standard biometric test methods to measure the rate and degree of biodegradation (Tier 2).
The data generated under Tier 1 evaluation and the determined time for the biodegradation in the chosen environment (Tier 2) allows ranking relative to other polymers evaluated under similar environmental conditions with this guide. The degree and time for biodegradation should be consistent with ASTM methods and any residues from the intermediate oxidation stage and from biodegradation must be shown to be environmentally benign and not persistent (Tier 3).
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