This International Standard specifies a method for determination of the temperature-retraction characteristics of extended vulcanized rubber. The temperature at which a specified retraction occurs is noted as the temperature is increased at a uniform rate after the rubber has been extended at room temperature and cooled to a sufficiently low temperature such that retraction does not occur upon release of the extending force.
NOTE — In addition to the two sizes of the standard test piece, other types of test piece cut from products are described. These do not necessarily give the same values of retraction temperature, and comparison between values obtained from different types of test piece is to be avoided.
DS/ISO 2921:1979 history
1979DS/ISO 2921:1979 Vulcanized rubber. Determination of low temperature characteristics. Temperature-retraction procedure (TR test)