There are two primary types of polyurethane: polyester and polyether. Both are useful in a multitude of industrial applications. Polyester urethane and polyether urethane are elastomers, meaning that they possess elastic properties, and both offer unique performance properties. So what are the main differences between polyester and polyether?

Up to 194°F (90°C), polyurethane elastomers can function continuously. If necessary, flame retardants may be used in the formulation. At high temperatures, polyether urethanes and polyesters both function well. However, polyesters are more heat-resistant and better able to tolerate high temperatures for longer.Polyethers are less prone to the development of dynamic heat.

Some items must rebound, or give back, the energy they receive. Compared to polyester polyurethane, polyether polyurethane has a greater rebound.

Although both polyether and polyester polyurethanes are robust, polyester polyurethanes are stronger in terms of tensile strength and cut and tear resistance.

The urethanes offer remarkable abrasion resistance, without a doubt. They outwear metals, plastics, and other rubbers significantly—frequently by an 8:1 or more ratio. Numerous processes, including impingement, erosion, impact, scuffing, and sliding, can cause abrasion.
Sliding is the term for rubbing and scraping abrasions. Particles or objects impinging on the urethane surface do so at a sharp angle.Abrasion resistance to sliding is greater in polyester polyurethane. This makes it more appropriate for uses like scraper blades.

As the temperature drops, polyurethane elastomers become more rigid. They may become brittle and less flexible as a result. The brittle point can range between -40°F and -100°F (-40°C and -73°C), depending on the formulation. Polyether polyurethane is less sensitive to cold temperatures than the other two varieties of polyurethane.Without splitting, polyurethanes can survive sharp decreases in temperature. Additionally, polyurethanes are more impact-resistant than other polymers, even at their highest hardness levels.

The reverse of rebounding is that you may occasionally want the object to absorb the energy it receives. In this situation, polyester urethane is preferable (for purposes like vibration dampening).

Polyurethanes made of polyester are more resistant to being exposed to chemicals, oils, or fuels.

Polyether and polyester polyurethane may be produced in a range of hardnesses, from soft to hard.

If the product will be submerged in water or subjected to high humidity, polyether polyurethanes should be chosen because of their superior hydrolytic stability.For extended periods of time, polyether polyurethanes can remain stable in water as warm as 122°F (50°C). They are not advised to be used continuously in water that is over 158°F (70°C). You may anticipate the weight increases by 3% to 1% as a result of water absorption, while the volume barely expands.It is not advised to use polyester polyurethanes in applications where moisture and excessive humidity are issues.