The issue of biodegradability has given rise to the long list of innovative materials in response to sustainability concerns. As defined, oxo-biodegradable is polyolefin plastic to which has been added amounts of metal salts. The degradation process is shortened from hundreds of years to years and/or months for degradation and thereafter biodegradation depends on the micro-organisms in the environment. The Oxo-Biodegradable Plastics Association provides the properties of oxo-biodegradable plastics where it stresses that such material does not leave fragments of petro-polymers in the soil; it is safe for long-term contact with foods; does not contain organo-chlorin, PCBs or heavy metals; does not emit methane or nitrous oxide, even deep in a landfill; can be safely recycled or can be composed in-vessel. Moreover, the association said that the oxo-biodegradable plastic material passes all the standard eco-toxicity tests.
Oxo-biodegradable plastics can be recycled or burned, if collected. However, if they are disposed recklessly, they will degrade and disappear, leaving no harmful residues. Exposure to sunlight and heat speeds up its degradation, but the process of oxo-biodegradation, once commenced, continues even in the absence of light as long as there is air around. Water, carbon dioxide and humus are the resulting components.
In terms of functional qualities, oxo-biodegradable plastics are no different from conventional plastics but on continuous exposure to UV and heat, they begin to degrade and biodegrade in finite number of years without the need for special decomposing conditions. The degradation timeline of such products is normally tailor-made according to applications. Generally oxo-biodegradable plastic bags are given to have a shelf life of one or two years but there are some applications where there is also secondary usage post recycling.
A report issued on oxo-biodegradable plastics by Aston University, UK states that the fundamental point about oxo-biodegradable technology is that the formulation turns ordinary plastic into a material of different molecular structure (in the presence of oxygen) by the end of its life. At that stage, the product is no longer a plastic and becomes a material which is biodegradable in the environment the same way as a leaf. It does not leave fragments behind, is non-toxic, does not block drains and is no longer a form of visual pollution.
It further states that oxo-biodegradable plastic biodegrades in a much shorter timescale than ordinary plastic. It does not contain heavy metals and it complies with EU and US regulations for direct contact with food.
The Middle East region has moved forward with its commitment to the environment by promoting oxo-biodegradable plastics and additives. In the July issue of the International Plastics News – Middle East and Africa, we look at the oxo-biodegradable plastics and its rising popularity in the region. For instance, in the United Arab Emirates the ban on plastic products except those made from oxo-biodegradable plastic is being implemented. Many supermarket chains and retail outlets in GCC countries particularly UAE, Qatar and Bahrain have already been seen using oxo-biodegradable plastic bags as a Corporate Social Responsibility (CSR) initiative.
As a result, demand for biodegradable additives has been on the rise providing opportunities to companies developing and supplying such products. It is anticipated that the switch to using oxo-biodegradable plastics by countries around the world through legislations aimed at reducing the impact of plastic wastes on the environment will pose faster growth and bright future ahead for new biodegradable materials and processing technologies.
