Flexible Polyurethane Foam Applications
Transportation
Flexible polyurethane foam (FPF) sees widespread use in transportation applications, including passenger vehicles, commercial vehicles such as trucks and busses, airplanes, boats, and other vehicles.
Above: Components of an automotive seat made with flexible polyurethane foam. Depending on the seat design, it may contain both molded foam and stabstock foam fabricated into specific shapes.
Since its creation, flexible polyurethane foam has seen use in transportation applications. Its light weight, cushioning, vibration and sound-absorption properties give it many uses.
Almost as soon as it became commercially available in the 1950s, flexible polyurethane foam found use in automotive, aircraft, boating, and other transportation applications. In cars, foam replaced cotton and other materials in seating, providing better comfort and more design options.
Since then, FPF use in transportation has grown dramatically, giving manufacturers more flexibility in design, efficiency, and safety.
Today, foam in transportation is used for:
- Seating
- Cabin comfort
- Sound absorption
- Vibration absorption
- Passenger safety
- Styling
- Weight reduction
- Functional items (such as filters and seals)
A modern automobile can easily have dozens of flexible polyurethane foam parts. Foam is also widely used in trucks, busses, aircraft, trains, and boats.
Benefits of FPF In Transportation Applications
Support
Flexible polyurethane foam is capable of providing the support necessary for long-term comfort, even in vehicle seats where a driver or passenger may sit for hours at a time. Foam prevents pressure points from bottoming out against the metal seat frame. In addition, foam helps keep the driver in the “H” point–the optimum height and posture for visibility.
Comfort: Softness And Firmness
FPF can be chemically engineered to be firm, soft, or something in between, making it ideal for creating comfort layers vehicle seating. Viscoelastic, or “memory” foam was first used by NASA to provide extra softness and to mitigate G-forces during takeoff and re-entry.
Comfort: Vibration Absorption
Foam seat cushioning and structural components help dampen road vibration that causes discomfort and fatigue. Foam seating works in conjunction with the vehicle suspension and tires to soften road bumps provide a smoother ride.
Versatility
Flexible polyurethane foam has multiple uses in modern vehicles: comfort and support in passenger seating, cushioning for safety in doors and dashboards, sound absorption in headliners and interior panels, weight reduction, seals, and filtration.
Comfort: Sound Absorption
FPF reduces sound and vibration from road noise, keeping interiors quieter for conversation and music.
Safety
In case of a collision, FPF is used in a variety of interior components to absorb impact and protect passengers.
Styling
Flexible polyurethane foam can be molded and cut into an almost infinite variety of shapes, giving designers tremendous freedom to create vehicle interiors.
Lightweighting
FPF’s light weight makes it a desired component for helping vehicle manufacturers reduce weight to help meet fuel efficiency standards and increase payloads.
Value
Foam’s cost effectiveness and versatility mean that it can enhance the value of vehicles, in terms of price, aesthetics, and safety.
Hygienic
FPF does not support the growth of mold or mildew, and enhances the effectiveness of vacuuming and other cleaning.
Recyclability
After their original use in a vehicle, many foam components can be recycled for use in other products, such as carpet cushion.
Aircraft seating must provide comfort for long periods of time, plus be lightweight to allow more passengers and cargo. Foam for aircraft is a specialty product, formulated to also meet stringent flammability standards.
FPF is ideal for boating applications because it’s impervious to moisture. It can also be easily fabricated to conform to the curves of boat interiors, and its light weight improves performance and can even help with flotation.
Several types of flexible polyurethane foam are used in transportation applications. For seating systems, molded polyurethane foam is used.
Chemicals are combined in a custom-shaped aluminum mold, where they react to form FPF. The finished foam is in the specific shape needed for the seat. It may also be in different densities and firmness levels to maximize comfort and support.
For sound and vibration damping, a vehicle manufacturer may use viscoelastic foam because of its ability to dissipate the frequencies that cause discomfort or distraction.
Slabstock foam may be used in multiple places for interior trim, including dashes, doors, and headliners. Foams can be formulated and fabricated so they adhere to the outer skins of components (like a dash) or to substrates. Such foams are typically thin.
For the interior roof of the cabin (or headliner), FPF may be flame laminated to fabric to prevent it from separating even after years of use. Headliners may even be thermoformed after lamination so that installation is easier and more precise.
FPF can also be used to provide seals around HVAC system parts to redirect condensation outside the vehicle. And in some vehicles and aircraft, reticulated foam (foam with larger air pockets) is used inside fuel cells for safety. In case of a crash, the reticulated foam helps prevent fuel from spraying and igniting, limiting fires.
Again, the versatility of FPF gives automotive designers and manufacturers many options for reaching their performance goals.
Looking To The Future
Challenges
The transportation industry is one of the most active areas for innovation in flexible polyurethane foam. Much attention is focused currently on the fate of products at the end of their life cycle. Recycling of foam in vehicle interiors is becoming more common. FPF recycling is one of the biggest recycling success stories in North America. Virtually all post industrial foam scrap and a growing amount of post consumer foam scrap is made into carpet cushion. Approximately 85-90% of the carpet cushion market is represented by bonded (or rebond) cushion products, made from recycled FPF. Bonded carpet cushion diverts more than 1 BILLION pounds of scrap FPF from landfills annually.
In addition, the automotive industry is exploring other FPF technologies, such as recycled and bio-based chemical precursors. As the automotive industry concentrates more on product life cycle, the flexible polyurethane foam industry will support it with innovative material science.
Related Resources
Related
Video: How Foam Is Made
Learn more about flexible polyurethane foam is made and how it is used in furniture, bedding, automobiles, carpet cushion and other uses.
Flexible Polyurethane Foam: A Primer
How FPF is made, specified and used in different applications.
Technical: Foam In Transportation
Detailed information foam used in transportation applications.
Technical: Molded Flexible Polyurethane Foam
Molded foam sees widespread use in vehicle seating applications.
Technical: FPF and Sustainability, Part 1
A detailed look the foam industry’s sustainability initatives.
Technical: FPF and Sustainability, Part 2
Foam recycling.
Technical: Viscoelastic Foam
A detailed look at Viscoelastic or “Memory” foam.
Technical: Foam Use For Passive Safety
Research on FPF use in vehicle cabins as a passive safety element.