scope:

This International standard specifies a method for the determination of the tendency of vulcanized rubbers to crystallize, and the time dependence of crystallization, by measurement of the recovery of compressed test pieces. Crystallization, which occurs more rapidly under high compression, reduces the recovery process. An alternative method of assessing the tendency to crystallize, based on measurements of increase in hardness, is given in ISO 3387. The latter requires longer test durations for vulcanizates, but the test method is applicable to both raw rubber and compounds.