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What is Polyurethane Foam?

Polyurethane foam is a versatile material widely used for cushioning in furniture, bedding, and packaging. Its unique ability to combine softness with support makes it a popular choice for comfort and protection. Comprising a complex chemical reaction, it can be tailored to various densities and firmness levels. Intrigued by its applications? Discover how it shapes the comfort of everyday life.
Adam Hill
Adam Hill

Polyurethane foam refers to a number of different types of foam consisting of polymers made of molecular chains bound together by urethane links. It can be flexible or rigid, but has a low density. Flexible polyurethane foam is most often used in bedding and upholstery, while the more rigid variety is used for thermal insulation and in automobile dashboards.

Flexible polyurethane is made in blocks and then cut to its desired shape. This is the way in which furniture cushions are made, for instance. Some materials can substitute for this application of polyurethane foam, such as polyester fiber or steel springs. However, polyester fiber does not recover nearly as well as foam does after compression. Steel springs recover well, but can become noisy as they get worn out. They also require some form of cushioning between them and the user.

A yellow mat made of polyurethane.
A yellow mat made of polyurethane.

In addition to the flexible and rigid types, semi-flexible polyurethane foam also exists, and is used extensively in automobile interiors. Seats, armrests, and headrests are frequently made from the semi-flexible variety of this material. In the case of seats, the foam is formed in a mold, and then removed and upholstered.

Rigid polyurethane foam has many relevant applications in construction. Many odd and detailed shapes such as sculptures and domed ceilings are far easier to make with foam than with wood. Some manufacturers sell a specialty rigid foam that is used to replace wood in carved signs and three-dimensional topography models. It is also used as home insulation, rigid boat hulls, tennis racket grips, and even surfboards.

Polyurethane foam insulation.
Polyurethane foam insulation.

Polyurethane foam can also be made into a form that sprays easily and then rapidly expands as it dries. It can be tailored to have many different physical properties, depending on the desired use. In this form it can be used as industrial insulation, and also as a roofing material that is waterproof and long-lasting. It is often applied to boats, ships, and floating docks. In higher-density forms, it has also been used to increase the structural strength of aircraft wings.

Polyurethane foam can be packaged for spraying.
Polyurethane foam can be packaged for spraying.

Spray polyurethane foam is one of the most versatile building materials in existence. It is also environmentally friendly in that it does not contain or give off any chemicals that are harmful to the environment or to general air quality. Even so, care must be taken when applying the foam, because the fumes that it does give off can be dangerous if not properly ventilated.

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Discussion Comments


How can polyurethane be used to resist heat in buildings?


I'm working in a foam factory and I started a few months ago. I want to learn what the reactions are of a polyurethane. Do you now anyone who is working at a foam factory? İf you are working in foam manufacturing, please help me because I really want to know.


For any women reading this, please make sure to check your bra label to see if the cups are made from polyurethane foam. Many people have an allergy to this material and should avoid it.


After shivering half of this winter I'm planning to use polyurethane spray foam insulation to get rid of the draughts in our old house.

I just bought a kit from the local home improvement store. It looks fairly simple to use and it's going to pay for itself real quick. I'm not a very confident DIY person but I am sure I can manage this!


@Evgeniy - It's cool to hear that you just sprayed polyurethane foam onto a wall to create a totally different look. I imagine it takes a little practice to get exact shapes, but rough designs would be much easier.

I will pass on this tip to my friend, who is involved in amateur theater productions. I know they are always looking for cost effective ways to build scenery. If it is fairly sturdy then even better, as it could be recycled in the future.


Polyurethane foam spray is a wonder for a set designer. It's amazing how quickly a flat wall can be transformed into a rocky cliff or stone parapet with this stuff. It is great fun. It does, however, require significant safeguards to work with safely. Protective apparel, including masks, is needed when actively working with the material as it does release some chemicals.. It is often cut, ground and sanded into shape when being used as a building material, and the particles are not safe to inhale, so make sure you wear your mask before starting in on it!

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    • A yellow mat made of polyurethane.
      By: Oleg Mitiukhin
      A yellow mat made of polyurethane.
    • Polyurethane foam insulation.
      By: PiLensPhoto
      Polyurethane foam insulation.
    • Polyurethane foam can be packaged for spraying.
      By: auremar
      Polyurethane foam can be packaged for spraying.
    • Polyurethane foam's low density is useful when making surfboards.
      By: maxoidos
      Polyurethane foam's low density is useful when making surfboards.
    • A face mask should be used when working with polyurethane foam.
      By: Johan Larson
      A face mask should be used when working with polyurethane foam.
    • Polyurethane foam may be used to construct the grips on tennis rackets.
      By: Michael Flippo
      Polyurethane foam may be used to construct the grips on tennis rackets.