Transport

Our world seems to have shrunk dramatically in the last few years. The public has embraced the opportunities offered by cheap travel. The tremendous expansion of low-cost airlines has been seen in every corner of the globe. Meanwhile, the cost of trains and car hire have dropped to compete.

A driving force behind this rapid expansion in travel has been the growth in developing and using new, strong materials, such as carbon composites, plastics and metal alloys. These lightweight material do not compromise on strength and safety. 

At the same time, many of these new materials – particularly plastics – are simpler and cheaper to form and mould. This has the overall impact of lowering the building costs of vehicles – be they aeroplanes, trains or cars. It also fits well with the growing ‘green agenda’ of lower fuel and energy consumption. 

However, with the deployment of new materials comes the challenge of ensuring their safety – including ‘fire safety’.

Plastics- the key to more climate-friendly air travel

In all modern aircraft, plastics are used for a vast range of internal parts, including sidewalls, bulkheads and overhead luggage bins. There are also synthetics used in seat padding and for carpets. Their use helps dramatically reduce the overall weight of the aircraft and thus improves its fuel economy. 

In an aircraft, any fire poses a huge threat to safety; clearly these new materials must be safe and fireproof. Fortunately, the use of modern flame retardants means that regulators around the world are happy to certify these novel materials as ignition resistant and safe for use in this most demanding of environments.

Plastics and synthetics are also no longer restricted to internal use. They are replacing traditional metals such as aluminium and titanium. One of the latest Airbus models, the A350XWB, uses carbon-fibre reinforced plastic extensively in its wing structures and fuselage; the Boeing 787 is 50% composites (but 80% volume).

In addition to their use in structural materials, plastics play other important roles. For example, an Airbus A380 requires an immense 500km of electrical cabling, required to control every aspect of the aircraft. All of this must be carefully insulated – indeed, a number of aircraft accidents have been attributed to faulty insulation.

High-speed trains – making overland journeys greener

The desire for faster, non-polluting trains have led manufacturers to take advantage of similarly strong yet lightweight plastics throughout the carriages. Indeed, as concerns over global warming continue to increase, more journeys will shift from aircraft to electric-powered trains. At the same time, there will be pressure to use lightweight materials – such as plastics – that can be easily and extensively recycled.

However, the threat posed by fire on a train is as real as on an aeroplane. The Channel Tunnel fire of 2008 – which fortunately took place on a freight train and did not lead to any deaths – caused extensive damage and led to a number of injuries. Fortunately, once again, modern flame retardants can be included in the new materials used to build these trains.

Cheaper, lighter and safer cars

For many people, personal transport will always mean a car. Here, plastics were once viewed as the ‘cheap’ option – wood and leather were the mark of quality. Nowadays, however, even the most upmarket cars now sport by feature high-quality synthetic materials in their structure, external panels and internal components. Meanwhile, ultrahigh-performance sports cars look to plastics and composites to save weight and maximise their aerodynamic qualities.

On a more day-to-day level, plastics and composites are increasingly important in mainstream cars. These are often used in out-of-sight locations, such as close to the engine or the rear of the dashboard, areas subject to high levels of heat from the engine or from onboard electronics. Nowadays, the average car contains 105 kg of plastics (9.3 percent of materials used), a level that will only increase in future. These applications are made feasible due to the presence of flame retardants within these plastics.

In future, plastics used in cars will need to adapt further, as new demands emerge. Cars are no longer exclusively powered by internal combustion engines alone – there are now electric vehicles – often relying on lithium ion batteries – and, in future, those powered by hydrogen fuel cells.