The carbon black content of an unvulcanized black or oil-black SBR masterbatch may be determined by this test method if an inert (CO₂) atmosphere and a determinate (see Note 2) of known carbon black content are available.

Note 2—Determinate black masterbatch may be prepared by careful addition of exact amounts of rubber and carbon black on a mill. An alternative would be a thorough blending of a quantity of black masterbatch and determination of the carbon black by use of a previously established determinate.

1.1 These test methods for the determination of the amount of carbon black in a masterbatch cover emulsion SBR-carbon black mixtures, but may be applicable to other polymers. Three test methods are included:

Note 1--The nomenclature used in these test methods is in accordance with Practice D1418.

1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.

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.