The packaging industry requires materials that are lightweight so as to reduce the amount used to package a product, thus reducing product weight for transportation cost savings as well as reducing amount of end-of-life packaging waste material.
Plastics have managed to fulfil this role very well and have remained unchallenged. As an example, one of the study revealed that the replacement of glass bottles with plastic bottles for beverage packaging in airlines resulted in savings of over USD 1 million in fuel costs as a result of the weight loss.
Fossil fuels are the main raw material used in the manufacture of plastics and in 2009 it was reported that up to 8% of world oil is channeled towards their production with 50% of it serving as feedstock and the other 50% as fuel for the conversion process.
In 2019, 10 years later, 10% of global oil production was used for plastic production with 40% of it dedicated to making single use plastics. The annual growth of plastics consumption shows that the estimated global plastic consumption by 2050 will be standing at 500 million tonnes of which single use products will be the major consumer.
The most used polymers for packaging are thermoplastic accounting for 84% of the plastic market share.
Petroleum based polymers which include polypropylene (PP), polystyrene (PS), polyvinylchloride (PVC), polyethylene (PE) and polyethylene terephthalate (PET) have been used extensively for packaging as a result of their light weight, good mechanical performance, good barrier properties among many other properties.
Many of these end up in landfills where they take centuries before they degrade.
They are responsible for a great amount of environmental pollution as they are nonbiodegradable. The packaging industry has begun using recyclable plastics in their designs as a means of reducing waste disposed into the environment. However, recyclers must maintain contaminants in the reformed plastic to sufficiently low levels acceptable for intended use of the resulting packaging.
This has proved difficult, time consuming and costly since the collected plastic waste consists of different plastic types that have to be sorted and separated.
After which, the plastic wastes may have to be washed clean to remove the different contaminate residues from products they were packaging.
Additionally, plastic additives such as the popular phthalates have been shown to be persistent in recycled plastic and continue posing health problems as they have low molecular weight and can easily migrate from plastics into packaged food or water.