OXO Biodegradable OXO-biodegradation is defined by CEN (European Standards Organization) {CEN/TR 1535-2006} as "degradation resulting from oxidative and cell mediated phenomena, either simultaneously or successively." It is sometimes described as "OXO-degradable" but this only describes the first or oxidative phases and this description should not be used for materials degraded by the OXO-biodegradation process defined by CEN. The correct description is "OXO-biodegradable."
There are two different types of biodegradable plastics:
- Vegetable based plastics (also known as bio-plastics bioplastics) or "compostable plastics"). It was tested in accordance with ASTM D6400 or EN13432 to decompose under conditions found in industrial composting or biogas facilities. This plastic can contain up to 70% oil derivative components
- Oil-decomposible plastic, made of polymers such as PE (polyethylene), PP (polypropylene), and PS (polystyrene) containing auxiliary materials (metal salts) and tested in accordance with ASTM D6954 or BS8472 or AFNOR Accord T51-808 to be degraded and decomposed in an open environment. These salts catalyze the degradation process to accelerate it so that the OXO plastic will be degraded abiotically at the end of its useful life in the presence of oxygen, much faster than ordinary plastic.
These are then converted into small chain organic chemicals such as ketones, alcohols, carboxylic acids and low molecular mass molecular hydrocarbons that are no longer plastic and can be decomposed by bacteria that are ubiquitous in terrestrial and marine environments. The time scale for complete bio degradation at any time or place in an open environment is much shorter than for "conventional" plastics which, in the normal environment, are very slow to decompose and cause large-scale damage.
Some countries in the Middle East are prohibited from using plastics unless they are upgraded with oxo-biodegradable technology.
Video Oxo Biodegradable
Process degradation
Degradation is a process that occurs in almost all materials. Conventional polyethylene (PE) and polypropylene (PP) plastics will usually split fairly quickly, but then it will take decades to become biodegradable. But the OXO-biodegradable product uses a catalyst to accelerate the molecular conversion of polyolefins and to incorporate oxygen atoms into the resulting low molecular mass molecules. This chemical conversion allows the further breakdown of matter by naturally occurring microorganisms, which utilize the material as a food source.
The first degradation process in OXO-treated plastic is oxidative chain imaging catalyzed by metal salts that lead to oxygenated short-chain (hydroxylated and dicarboxylated) molecules.
The OXO-bio plastic, if disposed in the environment, will be degraded into heavy molecular weight oxygen chains (usually MW 5-10 000 amu) in 2-18 months depending on the material (resin, thickness, anti-oxidant, etc.) and temperature other factors in the environment. Instead the ancient plastic will take decades to reach this stage, and in the meantime it will have the adsorbed toxins.
OXO plastics are designed so that they will not be degraded deep in the landfill and therefore they will not produce methane (a powerful greenhouse gas) under anaerobic conditions.
OXO-biodegradable products are not directly degraded in the open environment as they are stabilized to provide a useful service life product, where they are not damaged.
OXO-biodegradation of polymer materials has been studied in depth at the Technical Research Institute of Sweden and the Swedish University of Agricultural Sciences. The peer review report of the work was published in Vol 96 of the journal Polymer Degradation & amp; Stability (2011) on pages 919-928. This shows 91% biodegradation in the soil environment within 24 months, when tested in accordance with ISO 17556. It has been studied in the Eurofins laboratory in Spain and in many other laboratories around the world. It has been degraded in real time in seawater at the Banyul laboratory in France.
Maps Oxo Biodegradable
Standard implementation
Degradation of oXO decomposable plastic in the presence of oxygen, heat and UV light will speed up the process, but neither is necessary nor moist. Can be recycled for normal life with normal plastic. It is not designed to be compostable in an open industry composting facility in accordance with ASTM D6400 or EN13432, but can be satisfactorily compressed in the process on board.
The standards for industrial composting (EN13432 and ASTM D6400) require materials to convert to CO2 gas in 180 days because industrial composting has a short time scale and is not the same as degradation in the open environment. The leaves are generally considered to be biodegradable but will not pass composting standards due to the 180 day limit. (Indeed, materials compatible with ASTM D6400, EN13432, Australia 4736 and ISO 17088 can not be properly described as "compostable." This is because the standard requires it to substantially convert to CO2 gas in 180 days, You can not make it into compost - just being a CO2 gas. It contributes to climate change, but it does nothing to the ground.
Biodegradable biodegradable plastics in accordance with the American Standard (ASTM D6954) and British Standard (BS8472) which establish procedures for testing degradability, biodegradability, and non-toxicity, and by which a properly designed and manufactured OXO product must comply with this standard.. These standards contain pass/fail criteria.
No need to refer to Standard Specifications except special disposal routes (eg: composting), considered. ASTM D6400 Australian 4736 and EN13432 are Standard Specifications suitable only for the specific conditions found in industrial composting.
Another reference document was recently published by the French standard AFNOR organization. This document AC.51 808 offers a well-researched method for testing OXO-biodegradable plastics. by measuring ATP and ADP by chemiluminescence.
This French document is a very interesting innovation to predict the behavior of OXO-biodegradable plastic in terms of littering. This test method also provides an ecotoxicity testing method to ensure that residues in the environment, awaiting complete biodegradation, are non-toxic.
Environmental issues
Oil-degrated plastics, especially in the form of plastic bags, are now used in many places as a solution to the problem of plastic waste in the open environment. They are required in some areas of the Middle East, Asia and Africa. Legislation has been passed in 15 countries that support biodegradable biodegradable plastics and understate the use of conventional plastics by forbidding or burdening them. The use of oxo-degradable to solve waste in an open environment has been disputed.
Call to block
On November 6, 2017, the Ellen MacArthur Foundation publishes papers supported by 150 organizations, including M & S, PepsiCo and Unilever, support calls to ban biodegradable plastics. The report receives support from industry associations including the British Plastics Recycling Group and the Gulf Petrochemical and Chemical Association, NGOs such as the World Wildlife Fund (WWF), scientists including those based in Plymouth Marine Laboratory and ten MPs from nine EU countries.
The Oxo-Biodegradable Plastics Association (OPA) however, claims the report is not accurate. He argues many of the 150 organizations are aggressively promoting rival bio-plastic technology, while many of the others whose logo appears in the document itself are manufacturers of plastic goods that enter the open environment as waste. The paper's conclusion was rejected by Professor Ignacy Jacubowicz, who says the degradation process is not just fragmentation, but changes from high molecular weight polymers to bio-assimilated materials.
European Strategy for Plastics in a Circular Economy
On January 16, 2018, the European Commission published its report on the use of degradable plastics. This document forms part of the European Strategy for Plastics in the Circular Economy, which was released on the same day.
The Commission focuses on three major issues related to oxo-degradable: biodegradability of oxo-degradable plastic in various environments; environmental impact in relation to littering; and recycling.
The Commission finds no conclusive evidence that, in an open environment, oxo-degraded is fragmented to a fairly low molecular weight to allow for biodegradation. There is no conclusive proof of the time it takes for plastics that can be oxid-degraded to fragments in the marine environment, or about the degree of fragmentation. It says there is a big risk that fragmented plastics will not completely decompose, leading to subsequent risks of accelerated and accumulated microplastic counts, especially in marine environments. Rapid fragmentation increases the risk of microplastic ingestion by marine animals.
In light of littering, the report found that although it appears that the plastics industry that can be degraded with oxide can create products with minimal toxic impact on flora and fauna, it has not been conclusively proven that there are no negative effects. Ocso-degradable marketing as a solution to waste plastic in the environment can make it more likely that the goods are disposed of inappropriately and in the marine environment, fragmentation processes make the degradable plastic less likely to be recovered during the cleansing exercise.
The report was criticized by the Oxo-Biodegradable Plastics Association (OPA) and said the European Commission has failed to understand the difference between oxo-degradable and oxo-biodegradable plastics.
It accused the Commission of not listening to evidence related to the breakdown of oxo plastic, which maintained showing damaged plastic to molecular levels that could be bioassimilated. In relation to the time scale for biodegradation, the OPA says it is not useful to check how long it takes for a particular specimen for damage under certain conditions, due to the variability of environmental conditions. It says the key point is that biologically biodegradable plastics will break down faster than conventional plastics under the same conditions. Regarding recycling, they say their members have successfully recycled biologically degradable plastics for more than ten years, without any adverse reports. It rejected the Commission's view of littering and said that because oxid-degradable plastics can not be distinguished from other plastic products, they are unlikely to cause additional waste levels.
Source of the article : Wikipedia
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