Abrasion Resistance basically determines the overall resilience of rubber. Nitrile is a copolymer of butadiene and acrylonitrile. The popularity of nitrile is due to its excellent resistance to petroleum products and its ability to be compounded for service over a temperature range of -22°F to 212°F. Nitrile provides excellent compression set, tear, and abrasion resistance. The level of rubber abrasion resistance is directly related to the elastomer’s tensile strength.
NITRILE (NBR) Nitrile is the most widely used elastomer in the seal industry. The abrasion resistance is measured by moving a test piece across the surface of an abrasive sheet mounted to a revolving drum, and is expressed as volume loss in cubic millimetres or abrasion resistance index in percent. This is measured through the pressure unit of PSI (pounds per square inch) or MPa (megapascals). The values in parentheses are for information only. The major limiting properties of nitrile are its poor ozone and weather resistance and moderate heat resistance, but in many application these are not limiting factors. For volume loss, a smaller number indicates better abrasion resistance, while for the abrasion resistance index, a smaller number denotes poorer abrasion resistance. The rating of a material’s level of tensile strength is decided through the object’s ability to handle the maximum amount of stress put on it without breaking, tearing, or failing. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.