Standard Test Method For Carbon Black—Oil Absorption Number

Designation: D 2414 – 00a

Standard Test Method for

Carbon Black—Oil Absorption Number1
This standard is issued under the fixed designation D 2414; the number immediately following the designation indicates the year of original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A superscript epsilon (e) indicates aneditorial change since the last revision or reapproval.

1. Scope 1.1 This test method covers the determination of the oil absorption number of carbon black. 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. Itis 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. 2. Referenced Documents 2.1 ASTM Standards: D 1799 Practice for Carbon Black—Sampling Packaged Shipments2 D 1900 Practice for Carbon Black—Sampling Bulk Shipments2 D 4483 Practice for Determining Precision for Test MethodStandards in the Rubber and Carbon Black Industries2 D 4821 Guide for Carbon Black—Validation of Test Method Precision and Bias2 E 691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method3 3. Summary of Test Method 3.1 In this test method, oil is added by means of a constant-rate buret to a sample of carbon black in the mixer chamber of an absorptometer. As thesample absorbs the oil, the mixture changes from a free-flowing state to one of a semiplastic agglomeration, with an accompanying increase in viscosity. This increased viscosity is transmitted to the torquesensing system of the absorptometer. When the viscosity of the mixture reaches a predetermined torque level, the absorptometer and buret will shut off simultaneously. The volume of oil added isread from the direct-reading buret. The volume of oil per unit mass of carbon black is the oil absorption number. 3.2 Either DBP or paraffin oil is acceptable for use. While studies have shown either oil to exhibit comparable precision,
1 This test method is under the jurisdiction of ASTM Committee D24 on Carbon Black and is the direct responsibility of Subcommittee D24.11 on AbsorptiveProperties of Carbon Black. Current edition approved Nov. 10, 2000. Published January 2001. Originally published as D 2414-65T. Last previous edition D 2414-00. 2 Annual Book of ASTM Standards, Vol 09.01. 3 Annual Book of ASTM Standards, Vol 14.02.

paraffin oil offers the advantage of being non-hazardous; even FDA approved grades are available. For either oil, sections 8-11 (Calibration, Procedure,Calculation, and Report) are to be consistent with the oil selected for use. Referee testing between suppliers and users should use DBP oil until such time that precision data is available for paraffin oil. 4. Significance and Use 4.1 The oil absorption number of a carbon black is related to the processing and vulcanizate properties of rubber compounds containing the carbon black. 5. Apparatus 4 5.1Balance, analytical, with an 0.01-g sensitivity. 5.2 Oven gravity–convection type, capable of maintaining 125°C 6 5°C. 5.3 Spatula, rubber, 100-mm. 5.4 Absorptometer5, equipped with a constant-rate buret that delivers 4 6 0.024 cm3/min. 5.5 Desiccator. 6. Reagent and Standards 6.1 Purity of Reagents—Reagent grade chemicals shall be used in all tests. Unless otherwise indicated, it is intended thatall reagents shall conform to the specifications of the Committee on Analytical Reagents of the American Chemical Society, where such specifications are available.6 Other grades may be used, provided it is first ascertained that the reagent is of sufficiently high purity to permit its use without lessening the accuracy of the determination. 6.2 n-Dibutyl Phthalate, having a density of 1.042 to 1.047...