ASTM D3493-16

Standard Test Method for Carbon Black—Oil Absorption Number of Compressed Sample (COAN)

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.  
4.2 The difference between the regular oil absorption number and the oil absorption number of compressed sample is some measure of the stability of the structure of the carbon black.
SCOPE
1.1 This test method covers the procedure for the mechanical compression of a carbon black sample and the determination of the oil absorption number of the compressed sample.  
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.

General Information

• Status: Historical
• Publication Date: 31-Dec-2015
• ICS: 83.040.20 - Rubber compounding ingredients
• Technical Committee: D24 - Carbon Black
• Drafting Committee: D24.11 - Carbon Black Structure

Relations

• Replaces: ASTM D3493-14 - Standard Test Method for Carbon Black—Oil Absorption Number of Compressed Sample (COAN)
• Effective Date: 01-Jan-2016
• Replaced By: ASTM D3493-18 - Standard Test Method for Carbon Black—Oil Absorption Number of Compressed Sample (COAN)
• Effective Date: 01-Jul-2018
• Referred By: ASTM D4122-17(2023) - Standard Practice for Carbon Black—Evaluation of an Industry Reference Black
• Effective Date: 01-Jan-2016
• Referred By: ASTM D7854-21 - Standard Test Method for Carbon Black-Void Volume at Mean Pressure
• Effective Date: 01-Jan-2016
• Referred By: ASTM D7849-23 - Standard Classification for Nomenclature of Reference Materials of Committee D24
• Effective Date: 01-Jan-2016
• Referred By: ASTM D3053-23 - Standard Terminology Relating to Carbon Black
• Effective Date: 01-Jan-2016
• Referred By: ASTM D6915-23 - Standard Practice for Carbon Black—Evaluation of Standard Reference Blacks
• Effective Date: 01-Jan-2016
• Referred By: ASTM D1765-23a - Standard Classification System for Carbon Blacks Used in Rubber Products
• Effective Date: 01-Jan-2016
• Referred By: ASTM D4821-20 - Standard Guide for Carbon Black—Validation of Test Method Precision and Bias
• Effective Date: 01-Jan-2016
• Referred By: ASTM D5817-20 - Standard Practice for Carbon Black, Pelleted—Reduction, Blending, and Drying of Gross Samples for Testing
• Effective Date: 01-Jan-2016

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: D3493 − 16
Standard Test Method for
Carbon Black—Oil Absorption Number of Compressed
1
Sample (COAN)
This standard is issued under the fixed designation D3493; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope 3. Summary of Test Method
1.1 This test method covers the procedure for the mechani- 3.1 Asample of carbon black is compressed four times in a
compression cylinder at a pressure of 165 MPa (24000 psi)
cal compression of a carbon black sample and the determina-
tion of the oil absorption number of the compressed sample. and then tested in an absorptometer to determine the oil
absorption number.
1.2 The values stated in SI units are to be regarded as the
3.2 n-Dibutyl phthalate, paraffin, or EFA oil is added by
standard. The values given in parentheses are for information
means of a constant-rate buret to the compressed sample of
only.
carbonblackinthemixerchamberofanabsorptometer.Asthe
1.3 This standard does not purport to address all of the
sample absorbs the oil, the mixture changes from a free-
safety concerns, if any, associated with its use. It is the
flowing state to one of a semiplastic agglomeration, with an
responsibility of the user of this standard to establish appro-
accompanyingincreaseinviscosity.Thisincreasedviscosityis
priate safety and health practices and determine the applica-
transmitted to the torque-sensing system of the absorptometer.
bility of regulatory limitations prior to use.
When the viscosity of the mixture reaches a predetermined
torque level, the absorptometer and buret will simultaneously
2. Referenced Documents
shut off. The volume of oil added is read from the direct
2
2.1 ASTM Standards:
reading buret.The volume of oil per unit mass of carbon black
D1765Classification System for Carbon Blacks Used in
is the oil absorption number. Either DBP, paraffin, or EFA oil
Rubber Products
is acceptable for use with many standard pelleted grades of
D1799Practice for Carbon Black—Sampling Packaged
N-series carbon blacks found in Classification D1765. COAN
Shipments
testing using paraffin or EFAoil on some specialty blacks and
D1900Practice for Carbon Black—Sampling Bulk Ship-
powder blacks may result in significant differences when
ments
compared to COAN testing using DBP oil. Referee testing
D2414Test Method for Carbon Black—Oil Absorption
betweensuppliersandusersshoulduseDBPoiluntilsuchtime
Number (OAN)
that precision data is available for paraffin and EFA oils.
D4821Guide for Carbon Black—Validation of Test Method
4. Significance and Use
Precision and Bias
D4483Practice for Evaluating Precision for Test Method
4.1 Theoilabsorptionnumberofacarbonblackisrelatedto
StandardsintheRubberandCarbonBlackManufacturing
theprocessingandvulcanizatepropertiesofrubbercompounds
Industries
containing the carbon black.
4.2 The difference between the regular oil absorption num-
ber and the oil absorption number of compressed sample is
1
This test method is under the jurisdiction ofASTM Committee D24 on Carbon
some measure of the stability of the structure of the carbon
Black and is the direct responsibility of Subcommittee D24.11 on Carbon Black
black.
Structure.
Current edition approved Jan. 1, 2016. Published January 2016. Originally
3
5. Apparatus
approved in 1976. Last previous edition approved in 2014 as D3493–14. DOI:
10.1520/D3493-16.
5.1 Balance, analytical, 0.01-g sensitivity.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
3
Standards volume information, refer to the standard’s Document Summary page on Each apparatus is to be operated and maintained in accordance with the
the ASTM website. manufacturer’s directions for optimum performance.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

---------------------- Page: 1 ----------------------
D3493 − 16
8
5.2 Oven, gravity-convection type, capable of maintaining 6.5 ASTM D24 Standard Reference Blacks, SRB.
125°C 6 5°C.
7. Sampling
5.3 Carbon Black Press, capable of compressing a 25-g
4
sample to 165 MPa (24 000 psi). 7.1 Samples shall be taken in accordance with Practices
5 D1799 and D1900.
5.4 Absorptometer, equipped with a constant-rate buret that
3 3
delivers 67 6 0.4 mm /s (4 6 0.024 cm /min).
8. Calibration and Standardization
5.5 Spatula, rubber, 100 mm.
8.1 See Test Method D2414.
5.6 Sieve, 850 µm (U.S. No. 20), approximately 125-mm
NOTE 1—If values are not obtained within the acceptable range, it will
(5-in.) diameter with receiver pan.
b
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: D3493 − 14 D3493 − 16
Standard Test Method for
Carbon Black—Oil Absorption Number of Compressed
1
Sample (COAN)
This standard is issued under the fixed designation D3493; 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 (´) indicates an editorial change since the last revision or reapproval.
1. Scope
1.1 This test method covers the procedure for the mechanical compression of a carbon black sample and the determination of
the oil absorption number of the compressed sample.
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.
2. Referenced Documents
2
2.1 ASTM Standards:
D1765 Classification System for Carbon Blacks Used in Rubber Products
D1799 Practice for Carbon Black—Sampling Packaged Shipments
D1900 Practice for Carbon Black—Sampling Bulk Shipments
D2414 Test Method for Carbon Black—Oil Absorption Number (OAN)
D4821 Guide for Carbon Black—Validation of Test Method Precision and Bias
D4483 Practice for Evaluating Precision for Test Method Standards in the Rubber and Carbon Black Manufacturing Industries
3. Summary of Test Method
3.1 A sample of carbon black is compressed four times in a compression cylinder at a pressure of 165 MPa (24 000 psi) and
then tested in an absorptometer to determine the oil absorption number.
3.2 n-Dibutyl phthalate, paraffin, or EFA oil is added by means of a constant-rate buret to the compressed sample of carbon
black in the mixer chamber of an absorptometer. As the sample 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
torque-sensing system of the absorptometer. When the viscosity of the mixture reaches a predetermined torque level, the
absorptometer and buret will simultaneously shut off. The volume of oil added is read from the direct reading buret. The volume
of oil per unit mass of carbon black is the oil absorption number. Either DBP, paraffin, or EFA oil is acceptable for use with many
standard pelleted grades of N-series carbon blacks found in Classification D1765. COAN testing using paraffin or EFA oil on some
specialty blacks and powder blacks may result in significant differences when compared to COAN testing using DBP oil. Referee
testing between suppliers and users should use DBP oil until such time that precision data is available for paraffin and EFA oils.
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.
4.2 The difference between the regular oil absorption number and the oil absorption number of compressed sample is some
measure of the stability of the structure of the carbon black.
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 Carbon Black Structure.
Current edition approved July 1, 2014Jan. 1, 2016. Published December 2014January 2016. Originally approved in 1976. Last previous edition approved in 20132014 as
D3493 – 13.D3493 – 14. DOI: 10.1520/D3493-14.10.1520/D3493-16.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

---------------------- Page: 1 ----------------------
D3493 − 16
3
5. Apparatus
5.1 Balance, analytical, 0.01-g sensitivity.
5.2 Oven, gravity-convection type, capable of maintaining 125°C 6 5°C.
4
5.3 Carbon Black Press, capable of compressing a 25-g sample to 165 MPa (24 000 psi).
5 3 3
5.4 Absorptometer, equipped with a constant-rate buret that delivers 67 6 0.4 mm /s (4 6 0.024 cm /min).
5.5 Spatula, rubber, 100 mm.
5.6 Sieve, 850 μm (U.S. No. 20), approximately 125-mm (5-in.) diameter with rec
...