Plastics are some of the most useful materials on earth. Almost entirely man-made, they have become integral to modern life. But they can also present challenges to the environment and human health. Anyone who is interested in science, from the fundamentals of chemistry, or the properties of materials, to human health and the future of the planet needs to take an interest in plastics!
The first truly artificial synthetic plastic, ‘Bakelite’, was developed in 1907 and since then, many more plastics have been introduced (Thompson et al., 2009). Today’s plastics represent a great many inventions by a huge number of scientists from a number of disciplines that have developed into everyday materials in modern society. Plastics are rapidly increasing every year in their uses and applications.
Scientific research into plastics and their many applications are ongoing, with many thousands of papers published on the subject each year covering a range of scientific areas including biology, chemistry, environmental science, geology, health, materials science and physics. Exciting new applications appear daily, such as advances in 3D printing with plastics (Figure 1), novel antibacterial plastics and the development of new bioplastics that are not derived from petroleum.
Unfortunately the long lifetime observed for many plastics, although hugely beneficial in many applications, can also lead to problems at their end of life disposal. In particular when they are carelessly disposed of within the environment (figure 2, Smith et al., 2014). Currently there is growing concern over tiny pieces of plastic or so-called microplastics that originate from domestic products or activities such as laundry (Welden) and their effect upon the environment.
This is why appropriate rubbish collection and recycling options (Figure 3) are of growing concern for society. If a waste plastic is to be recycled, then logically the ease with which this can be performed depends on how many other types of plastic and other materials are present in the whole of the waste sample.
The easiest way to deal with plastics is to reuse the materials in a similar application if this is appropriate. Alternatively if this is not possible then disposal to landfill is relatively simple but this is not very satisfactory or sustainable as it represents a waste of a potential resource. A slightly better option is to burn the plastic within a refuse-derived-fuel to recover the energy trapped within the materials, this is often the best option for highly contaminated plastics.
A better solution to waste plastics, if simple reuse isn’t practical, is to recycle the plastic materials. This is often so-called materials recycling where the plastic is separated, shredded and re-melted to form a new product. Alternatively if appropriate the plastic may be chemically recycled by carefully breaking it down to recover the original chemicals used to make it, so that these chemicals can be reused (Carné and Collinson 2011) to reduce the use of oil derived resources.
Another alternative is to develop bioplastic materials that are formed from renewable resources. Part of the rational for their use is that at the end of their life if carelessly discarded in the environment then they will be biodegradable (Boardman) so that they will eventually breakdown.
Hopefully now you will appreciate that plastics offer a great many benefits for society and that with further ongoing scientific research combined with better waste treatment plastics can stop being a burden on the environment.
This material was adapted in part from the Open University course S350 Evaluating Contemporary Science, see the following link for further details of this course http://www.open.ac.uk/courses/modules/s350
References and further articles
Boardman, C., New biodegradable materials could replace plastic bags, available at
Carné Sánchez, A. and Collinson, S.R., (2011) ‘The selective recycling of mixed plastic waste of polylactic acid and polyethylene terephthalate by control of process conditions’, European Polymer Journal, vol. 47, no. 10, pp. 1970–6 [Online]. Available at http://oro.open.ac.uk/31292/ (Accessed 1 June 2016).
Thompson, R. C., Swan, S. H., Moore, C. J. and vom Saal, F. S. (2009) ‘Our Plastic Age’, Philosophical Transactions of the Royal Society B: Biological Sciences, vol. 364, no. 1526, pp. 1973–6.
Introduction to polymers available at http://www.open.edu/openlearn/science-maths-technology/science/chemistry/introduction-polymers/content-section-0
Smith, J. (2014) UNEP Year Book 2014 emerging issues update ‘Plastic Debris in the Ocean’, [Online].Available at http://www.unep.org/yearbook/2014/PDF/chapt8.pdf (Accessed 10 August 2016).
Welden, N., How your pile of laundry fills the sea with plastic pollution, available at