Plastics are vital within the modern automotive industry for various reasons, such as reducing a vehicle’s weight to improve fuel efficiency and helping to keep the driver and passengers safe.
A variety of plastic materials, each with distinct properties, is used for specific parts of the vehicle. From thermoplastics to engineering resins, the plastic type is chosen based on factors such as flexibility, weight and durability.
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Used in many parts of a car, plastics form the dashboard, door handles, fenders, engine covers, carburettors, seats and more.
The most common types of plastic used for vehicles include polyurethane, polypropylene, polyvinyl chloride, acrylonitrile butadiene styrene and polycarbonate.
Benefits of plastic in cars
Automotive plastics play many roles, with one of the most important being weight reduction. Using lightweight plastics rather than metals can significantly improve a vehicle’s fuel efficiency. Research suggests every weight reduction of 10% can reduce emissions and improve fuel efficiency by around 7%, leading to cheaper running costs.
Vehicle safety is also improved; plastics absorb and redistribute energy in the event of an accident. One such example is fibre reinforced polymer crumple zones, which can keep vehicle occupants safe by absorbing four times more impact than their steel counterparts, reducing injuries.
Safety features such as seat belts, airbags and energy absorbing bumpers rely on the latest plastic materials. Car airbags and seat belts are typically made from nylon and PVC-coated fabric, which is a fire-retardant material vital in the event of an accident, when fire could be a real threat.
Design flexibility
The ability to mould plastics into a wide range of custom shapes for different designs leads to greater flexibility when compared with metal. Due to the complex processing cycle needed to shape metal parts, plastic is the more cost-effective option.
Creating aesthetically pleasing designs is easier, as plastic is more versatile than metal and also resistant to rust and corrosion, even when exposed to harsh weather conditions. Plastics provide automobile designers with amazing flexibility, enabling customisable interiors, innovative shapes and improved aerodynamics.
Plastic casings for electric vehicle batteries can make them more affordable, encouraging more motorists to use this sustainable solution.
Future of plastics in automotive manufacturing
Plastics are playing an increasingly significant role in operating advanced driver assistance systems, including automated emergency braking, which relies on plastic for the multitude of sensors and cameras required.
A report released in May 2024, Chemistry and Automobiles, found the average amount of plastics in a car has increased by 18% during the past decade. It now accounts for 10% of an average car’s total weight and 50% of its volume, helping to drive fuel efficiency.
Electric vehicle production is spearheading the increased demand for plastics in the automobile sector, as an average medium sized EV contains around 45% more plastic than a similar sized petrol or diesel powered car.
Autonomous driving
As the automotive industry embraces new technologies, such as autonomous driving, will the role of plastics evolve too? The answer is yes, according to the experts, as plastic can be used to create sensor housing, lightweight structures and modern vehicle interiors.
Protecting sensitive components such as sensors from environmental influences including humidity, heat and road salt in icy weather is vital to ensure autonomous vehicles can continue to operate safely, whatever the conditions. In addition, plastics can help with cybersecurity by preventing physical and wireless intrusion into autonomous vehicles. Inside the vehicle, they can provide durable information and entertainment display screens that are scratch, chemical and shatter-resistant.
Environmental impact
The trend of incorporating more plastic products into automobiles shows no sign of slowing down, as manufacturers, industry regulators and consumers all want the same thing: safer vehicles that are more technologically advanced, but at a cost-effective price that motorists can afford.
Industry experts anticipate an increasing amount of plastic will be used for automobiles in the foreseeable future to meet growing technological and sustainability demands. Using plastics can also aid sustainability by reducing the environmental impact of vehicles, as they can be designed to be recyclable at the end of their lifespan
