Ester & Ether – The Polyurethan Sisters

A common question when it comes to polyurethane tubing, is the difference between the two polyurethanes: ester-based and ether-based.

For the chemists in the crowd, ether has two carbons bonded to an oxygen atom. Ester however has a double oxygen bond with a carbon atom.

Practically speaking, there’s a trade-off to be made by the user. The ester-based resin handles oil slightly better but it degrades quickly when introduced to moisture. The ether-based resin handles oil slightly less well, and handles water very well. In fact, ether-based polyurethane is an excellent choice for water applications.

To me, the ether-based resin is an easy choice. The ester though is a little cheaper and is the material you often see in inexpensive imported tubing. In fact, if you see polyurethane tubing for sale at a discount house and are marveling at the low price, you’re most certainly looking at ester-based material. You won’t be able to tell the difference until it gets wet.


RMW Pneus Purpose


The RMW Pneus is a blog that will contain information about components for industry that utilize fluid power, automation control, electrical controls, and safety products.  Brands that are discussed are directly represented by the R.M. Wright Company which is based in Farmington Hills, Michigan.  Please feel free to share information you discover with other individuals in your organization or with customers you service.

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