Polymers processed from petroleum take decades to decay and cause significant environmental problems, including pollution and hazards to wildlife. Designers and scientists have emphasised the need to develop ‘plastics’, that degrade / decomposed, quickly and harmlessly in the environment. This has lead to the development of bio-degradable polymers, including oxo-degradable polymers.
Oxo-degradable polymers / plastics are processed from oil, although they degrade over several months in soil and landfills, due to the action of oxygen and micro-organisms. They are regularly used by the packaging industry and promoted as environmentally friendly. Polyethylene is frequently the basis of oxo-degradable plastcs.
They are processed from petroleum based polymers and contain additives such as metal salts (bio-batch). When ‘dumped’ in a landfill site and covered with soil, the additives encourage the molecular structure of the ‘plastic’ to change into a food source, for micro-organisms. They bio-degrade into carbon dioxide and water. This is called an abiotic process (degradation by oxidation).
POLYPROPYLENE (PP)
POLYVINYL CHLORIDE (PVC)
POLYETHYLENE TEREPHTHALATE (PET, PETE)
POLYSTYRENE (PS)
LOW DENSITY POLYETHYLENE (LDPE)
HIGH DENSITY POLYETHYLENE (HDPE)
Oxo-degradable plastics do not degrade entirely, as they leave behind a non-toxic, harmless powder. Therefore, it is sometimes argued, that oxo-degradable plastics are not completely environmentally friendly.
As they are derived from petroleum based polymers, they are not completely renewable. However, they can be recycled, even when ‘mixed’ with ordinary plastics and they do not require separate collections. Oxo-degradable polymers, have a lower environmental impact, compared to normal petroleum based plastics.
As they are derived from petroleum based polymers, they are not completely renewable. However, they can be recycled, even when ‘mixed’ with ordinary plastics and they do not require separate collections. Oxo-degradable polymers, have a lower environmental impact, compared to normal petroleum based plastics.
Oxo-degradable polymers have a range of practical applications (see below), including degradable bags for medical use. They have been tested over time and have been found to be safe for food packaging.
