Why is polyurethane important in the automotive industry?

14th November, 2025

Used in various interior and exterior components, polyurethane is used for suspension, bodywork and coatings in classic car restoration, to absorb forces, minimise movement in the chassis and improve aerodynamics in motorsport, and in road cars, where polyurethane is used in seats, headrests, bumpers, door panels, seat frames and dashboards for cushioning and sound dampening.

At Aquaseal Rubber, we design and manufacture bespoke polyurethane parts for the automotive industry, like when we were tasked with replicating a seal for a classic Alvis car and created post-war car parts for Triumph Roadster Club.

Choosing rubber or polyurethane is crucial when replacing or improving an aspect of any vehicle. Whether you’re looking for polyurethane to replace a suspension part or bumpers and door panels, we can work to your bespoke requirements.

This guide will highlight what polyurethane is, polyurethane uses in automotive and its benefits for applications across road cars, classic cars and motorsport, like racing and rally cars.

What is polyurethane?

Polyurethane is a tough but gentle alternative to rubber and plastic materials.

Polyurethane hardness is measured on a Shore scale and ranges from very soft Shore (25) to very hard shore (90+); the hardness is a key property for selecting the right material for applications. This scale means polyurethane can be manufactured as anything from the softness or a pencil rubber to something harder than nylon and anywhere in between.

Its universal application means polyurethane can be found in domestic applications – like furniture and bedding – to industry applications – including thermal insulation and coatings.

What is polyurethane used for in the automotive industry?

The automotive industry encompasses the design, manufacture, sale and servicing of motor vehicles. The principal products in the industry are passenger automobiles – like road cars – and light trucks, including pickups and vans, but automotive industry also includes classic cars and racing and rally cars.

Polyurethane is used across all of these sectors within the wider automotive industry.

Road cars

From the 1960s, polyurethane was adopted by the automotive industry for many uses.

Polyurethane (PU foam) was originally invented in 1954 and from then, manufacturers began to integrate rigid PU foam into the panels of many vehicles. Now, polyurethane in road cars is used in car seats, bumpers, suspension insulators and many other interior components.

It is a top choice in road cars because it improves both user experience and overall performance of a vehicle through:

• Better fuel economy due to weight reduction
• Comfort
• Resistance to deterioration and corrosion
• Heat insulation
• Sound and energy absorption

While safety is priority in road cars, polyurethane can support the aesthetic of a car because it can be produced in various densities, maximising the design capabilities, and it provides support for passengers without losing its shape.

Polyurethane is sturdy but lightweight, meaning it can withstand impacts in road traffic accidents and it reduces our impact on the environment by reducing fuel consumption as a result of its lightweight nature.

Classic cars

Sometimes, in classic cars, standard seals don’t always work when trying to repair a certain aspect of the vehicle. Traditional rubber parts for classic cars might not always provide the same level of durability and longevity.

Polyurethane is an alternative choice when maintaining or repairing classic cars, especially because it is durable and can enhance performance, as well as being a useful choice for interior components, adhesives and coatings.

In a classic car, polyurethane may be used in suspension bushings – one of the most popular upgrades by replacing the original rubber components – adhesives and sealants to bond panels or sealing components like windows, doors and lights, and coatings and paint, since polyurethane coatings provide scratch and rust resistance. On the interior, polyurethane can be used to restore classic car seats to provide improved cushioning, as well as dashboard finishes. Polyurethane also has excellent insulation qualities, reducing noise and control thermal stability.

Racing and rally cars

Due to its versatility and ability to be engineered into components with different stiffnesses, polyurethane is ideal for the demanding nature of motorsport.

In race cars, polyurethane is used for its superior strength, durability and shock-absorbing properties to improve performance, handling and safety. It can be found in suspension bushings, engine and gearbox mounts and to support the aerodynamics of a car through coatings and foam cores.

Aside from racing cars, polyurethane can also be found in trolley and pit equipment wheels and protective films on hire-wear areas of a racing car.

In rally, cars heavily rely on suspension bushing in control arms, sway bars and shock mounts. Rally cars also contain polyurethane in seat inserts, to absorb energy and for extra safety. In rallying, polyurethane is all about durability and protection.

What are the benefits of using polyurethane in the automotive industry?

Polyurethane offers several benefits to the automotive industry, regardless of whether it is used in road, classic or racing cars. These benefits include:

• Weight and fuel efficiency: polyurethane’s lighter weight means it reduces the overall weight of a vehicle, contributing to less fuel consumption which reduces environmental impact
• Comfort and design: polyurethane is used in seating because of its cushioning and ergonomic support, especially since it comes in various densities and types, meaning it can be moulded into different shapes
• Durability and performance: polyurethane is resistant to abrasion, friction and wear, so it maintains its shape and properties over time, but it also resists oil, moisture, chemicals and UV radiation to prevent damage to the vehicle by absorbing impact
• Insulation: polyurethane absorbs engine and external noises, traps air and minimises heat transfer and absorbs shock and vibrations, to improve user experience in any vehicle
• Cost and sustainability: polyurethane has a long service life, with reduced maintenance requirements, which makes it a cost effective choice for users, and it can also be recycled to help manufacturers reduce their environmental footprint

Before choosing the hardness of polyurethane for your application, it is important to consult an essential guide to polyurethane or discuss your bespoke requirements with an expert in the manufacturer of materials like rubber or polyurethane.

Choosing Aquaseal to manufacture polyurethane for the automotive industry

At Aquaseal Rubber, we design and manufacture a range of materials, including polyurethane, from our Longbenton-based factory and supply clients across the world with bespoke rubber solutions.

If you’re looking to repair or maintain an automotive vehicle, from your road car or classic car to a racing car, our team are on hand to support you. Contact us to see how we can work together.