Carboxylated Nitrile (XNBR) is one of the many types of nitrile on the market today. It exhibits lower high temperature limits and warmer low temperature limits than standard nitrile materials. Reacting a nitrile base polymer with a carboxylic acid dramatically improves the wear resistance of the nitrile material.
An appliance manufacturer was using a competitor's nitrile o-rings in a pneumatic application. They were experiencing failures due to excessive wear of the seals.
Parker O-Ring Engineering suggested using compound N1090-85. This compound is an extremely low friction XNBR. After testing the N1090-85 in the penumatic application, the material offered significant friction reduction and wear resistance, greatly improving the service life of the o-rings.