Learning the basic chemical properties of everyday materials isn’t fun (unless you’re a chemist), but sometimes it’s necessary when an important part needs replaced. Ester- and ether-based items, for example, are similar but have distinctions that matter in manufacturing.

Following is an explanation of the differences between ester and ether, and what they are best used for.

Recognizing the difference between Ester and Ether

Although ester and ether are similar in terms of chemical make-up, small differences make an impact on their basic properties. For instance, ester polyurethane degrades when exposed to water or high humidity, whereas ether performs well in water. In certain uses, ester can be more rigid and stiff, and ether can be flexible and soft. Both ester and ether can be used for oil and gasoline functions.


The Differences Between Ester And Ether PolyurethaneThe foam material you lounge on to watch TV and that you rest your weary head on at night are made of ether or ester polyurethane. Ester-based foam is stronger and more supportive than ether-based foam. As such, ester-based foam is used for shock-absorbent packaging, dissipating electric shock and in household materials like cleaning sponges and mops.

Ether-based foam is softer, more flexible and is used more than ester foam. Because of ether’s resistance to water damage, it is able to be used as foam in outdoor furniture and boat cushions. In addition to being used for furniture cushioning, it can also be used for speaker foam to absorb sound, and air filter foam to filter dust and allergens.


Ester- and ether-based polyurethane hoses are essential for safely moving air, water, oils and other chemicals from one place to another. Polyurethane hoses are used for pneumatic systems — like assembly lines, compressed-air systems and gas-operated systems — because of their resistance to water, oils, gasoline and other chemicals.

Since ether-based hoses are resistant to water, they’re typically used as garden hoses and in car washes, and they are also certified to use for potable water. Ester-based hoses work best for any chemical- and petroleum-related functions, such as in laboratories and gas station pumps.


O-rings have a number of different uses. Polyurethane O-rings, specifically, are used in hydraulic, high-pressure and pneumatic systems due to their resistance to chemical degradation and ability to withstand high temperatures and wear-and-tear. They are typically designed to block air or fluid from entering part of a device. As stated earlier, ester degrades when exposed to water, so avoid using ester-based polyurethane O-rings on water-based systems.

It’s important to know the differences between ester- and ether-based polyurethane before purchasing a product. Make sure you know which polyurethane base is best when you have to replace hoses or other parts.