ASTM D926-08

The plasticity number and the recovery of the test specimen are related to the flow properties and the elastic properties, respectively, and may be useful in predicting processing characteristics, such as ease of forming and extrusion characteristics.

In this test method, plasticity is measured in an inverse manner, as noted by the final height of the specimen. Thus, high plasticity rubbers (high degree of flow during test) are indicated by a low plasticity number.

1.1 This test method covers the determination of plasticity and recovery of unvulcanized rubber by means of the parallel plate plastometer. Uncompounded, compounded, and reclaim rubber may be tested.

Note 1—ISO 2007 and Test Method D 3194 use a principle similar to this test method although the apparatus, test conditions, and procedure are different.

1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. 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.