Applications and societal benefits of plastics

Abstract

This article explains the history, from 1600 BC to 2008, of materials that are today termed 'plastics'. It includes production volumes and current consumption patterns of five main commodity plastics: polypropylene, polyethylene, polyvinyl chloride, polystyrene and polyethylene terephthalate. The use of additives to modify the properties of these plastics and any associated safety, in use, issues for the resulting polymeric materials are described. A comparison is made with the thermal and barrier properties of other materials to demonstrate the versatility of plastics. Societal benefits for health, safety, energy saving and material conservation are described, and the particular advantages of plastics in society are outlined. Concerns relating to littering and trends in recycling of plastics are also described. Finally, we give predictions for some of the potential applications of plastic over the next 20 years.

Figure 1.

World plastic materials demand by resin types 2006 (PlasticsEurope 2008).

Figure 2.

Market share of various materials used for the packaging of soft drinks 1998–2007 (Canadean 2008). Notes: (i) combined total volume for 32 European countries; (ii) packaged water, carbonates, juice, nectars, still drinks, iced tea and coffee, sports drinks, energy drinks, squash/syrups, fruit powders; (iii) ‘others’ include metal (cans), board (cartons), foil (pouch) and other types of plastics. (Diamonds, % glass share; circles, % PET share; triangles, % others.)

Figure 3.

Material and energy savings can be made by replacing composites, such as gable top cartons (a), and glass containers (b, left) with plastic pouches (b, right).

Figure 4.

Schematic of various modes of recycling available for plastics. Not shown in the figure is waste-to-energy conversion via incineration. E_i is the energy per unit mass associated with processing M_i units of material. M_i may not be the same for all values of i because of incidental losses.