Automotive applications

The plastics revolution

Vehicle manufacturers recognise the design, weight and cost benefits of plastics and today’s average car contains more than 1,000 plastic parts.  Approximately 12 per cent of all of these by weight are made of soft PVC, principally as underbody coatings and sealants, wire harnesses, passenger compartment parts and small exterior trims and fittings.

Vital protection

More than any other technical advance, soft plasticised PVC used as a protective layer for the chassis has doubled the normal in-service life of modern vehicles and drastically reduced the need for servicing and repairs.  This layer is produced as a liquid – or ‘plastisol’ - typically using phthalates.  Car manufacturers spray the plastisol onto the metal underside of the chassis where it solidifies into a thin but extremely tough surface during the stoving (heating) of the paint.  The chassis is protected against grit, dirt and water thrown up from roads and rust and corrosion are dramatically reduced.  The coating is light and so does not increase the petrol consumption of the car and requires no further servicing.  As it is sprayed on, all metal parts are equally protected, even those which are recessed.

Soft PVC makes modern vehicles safer and more reliable through its use as a protective sheathing for electrical wires in all areas of cars and lorries.  The material has the strength to resist shocks from the road but the flexibility to cope with the many sudden movements to which vehicles are subjected. 

For sensitive wires around the engine particular members of the plasticiser family, trimellitates, can be specified to give crucial temperature resistance qualities to the PVC wires.  These wires have to be able to withstand heat when the engine is in service while resisting cold at other times, for example, if the vehicle is left outdoors in winter or cold climates.  Without them, cars would be less safe and more unreliable.

Comfort and safety

Plasticised PVC plays a role in reducing injuries and enhancing the appearance of cars.  Soft PVC dashboards, for example, cushion impact in accidents.  In luxury cars, this panel is made from PVC to look and feel like leather while retaining all the safety advantages of the polymer.  Cars are also quieter now thanks to the sound-dampening properties of soft PVC.

The versatility of the material enables manufacturers to achieve exact size, shape and texture specifications for door panels, arm rests, sun visors, rain strips and other, small parts. Soft PVC meets the challenge of difficult shapes much more easily than alternatives on either price or quality.

Externally, soft PVC protects vulnerable areas such as doors, from small impacts and scratches.  It is found in body side protection strips, weather strips and window sealing profiles.  Thanks to phthalates, the degree of softness of these parts can be precisely determined so that they are robust but soft enough to reduce injuries to pedestrians.

Cost-effective and environmentally sound

Plasticised PVC offer unbeatable cost-effectiveness.  It helps to make cars and lorries more affordable and to bring the benefits of mobility to more groups within society.   For the environment, the lightness of soft PVC parts reduces the weight of vehicles, lowering wear and tear on roads and reducing fuel consumption.