1、Designation: D2414 18aStandard Test Method forCarbon BlackOil Absorption Number (OAN)1This standard is issued under the fixed designation D2414; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number in
2、 parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the U.S. Department of Defense.1. Scope1.1 This test method covers the determination of the oilabsorp
3、tion number of carbon black.1.2 The values stated in SI units are to be regarded as thestandard. The values given in parentheses are for informationonly.1.3 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of th
4、is standard to establish appro-priate safety, health, and environmental practices and deter-mine the applicability of regulatory limitations prior to use.1.4 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Dec
5、ision on Principles for theDevelopment of International Standards, Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2D445 Test Method for Kinematic Viscosity of Transparentand Opaque Liquids (and C
6、alculation of Dynamic Viscos-ity)D1218 Test Method for Refractive Index and RefractiveDispersion of Hydrocarbon LiquidsD1765 Classification System for Carbon Blacks Used inRubber ProductsD1799 Practice for Carbon BlackSampling PackagedShipmentsD1900 Practice for Carbon BlackSampling Bulk Ship-mentsD
7、4052 Test Method for Density, Relative Density, and APIGravity of Liquids by Digital Density MeterD4483 Practice for Evaluating Precision for Test MethodStandards in the Rubber and Carbon Black ManufacturingIndustriesD4821 Guide for Carbon BlackValidation of Test MethodPrecision and BiasD5554 Test M
8、ethod for Determination of the Iodine Value ofFats and Oils2.2 DIN Standards:3DIN 16945 Testing of resins, hardeners and accelerators, andcatalyzed resinsDIN EN ISO 660 Animal and vegetable fats and oils -Determination of acid value and acidity3. Summary of Test Method3.1 In this test method, oil is
9、 added by means of aconstant-rate buret to a sample of carbon black in the mixerchamber of an absorptometer. As the sample absorbs the oil,the mixture changes from a free-flowing state to one of asemiplastic agglomeration, with an accompanying increase inviscosity. This increased viscosity is transm
10、itted to the torque-sensing system of the absorptometer. When the viscosity of themixture reaches a predetermined torque level, the absorptom-eter and buret will shut off simultaneously. The volume of oiladded is read from the direct-reading buret. The volume of oilper unit mass of carbon black is t
11、he oil absorption number.3.2 Either DBP, paraffin or Epoxidized Fatty Acid Ester(EFA) oils are acceptable for use with most standard pelletedgrades of carbon black including N-series carbon blacks foundin Classification D1765. OAN testing using paraffin or EFAoils on some standard blacks and special
12、ty blacks includingpowder products may result in unacceptable differences ascompared to OAN testing with DBP oil. Paraffin and EFA oilsare considered non-hazardous; some paraffin oils are FDAapproved. For any of the oils, Sections 812(Calibration,Procedure, Calculation, and Report) are to be consist
13、ent withthe oil selected for use. Referee testing between suppliers andusers should use DBPoil until such time that precision data areavailable for alternate oils.1This test method is under the jurisdiction ofASTM Committee D24 on CarbonBlack and is the direct responsibility of Subcommittee D24.11 o
14、n Carbon BlackStructure.Current edition approved Dec. 1, 2018. Published January 2019. Originallyapproved in 1965. Last previous edition approved in 2018 as D2414 18. DOI:10.1520/D2414-18A.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at servic
15、eastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Available from Deutsches Institut fur Normung e.V.(DIN), Burggrafenstrasse 6,10787 Berlin, Germany, http:/www.din.de.Copyright ASTM International, 100 Barr Harbor Drive, P
16、O Box C700, West Conshohocken, PA 19428-2959. United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recommendations issued
17、by the World Trade Organization Technical Barriers to Trade (TBT) Committee.14. Significance and Use4.1 The oil absorption number of a carbon black is related tothe processing and vulcanizate properties of rubber compoundscontaining the carbon black.5. Apparatus45.1 Balance, analytical, with an 0.01
18、-g sensitivity.5.2 Oven, gravity-convection type, capable of maintaining125 6 5C.5.3 Spatula, rubber, 100-mm.5.4 Absorptometer, equipped with a constant-rate buret thatdelivers 4 6 0.024 cm3/min.5.5 Desiccator.6. Reagent and Standards6.1 Purity of ReagentsReagent grade chemicals shall beused in all
19、tests. Unless otherwise indicated, it is intended thatall reagents shall conform to the specifications of the Commit-tee on Analytical Reagents of the American Chemical Society,where such specifications are available.5Other grades may beused, provided it is first ascertained that the reagent is ofsu
20、fficiently high purity to permit its use without lessening theaccuracy of the determination.6.2 n-Dibutyl Phthalate, having a density of 1.042 to 1.047Mg/m3at 25C and a relative density of 1.045 to 1.050 at 25C.6.3 Paraffn Oil, having a kinematic viscosity of 10 to34 mm2/s (cSt) at 40C.NOTE 1Three p
21、araffin oils have been found suitable including Marcol82 from Exxon, 80/90 White Oil from Conoco-Phillips, and LC1 oil fromLab Chemicals, Germany. All three oils are pharmaceutical or food gradeoil, or both, based on available data.6.4 Epoxidized Fatty Acid Ester (EFA), meeting the speci-fications l
22、isted in Annex A4. It is recommended to store theproduct at temperatures between 7 and 30C. If stored in sealedoriginal containers, the product is stable for at least 12 months.For handling and safety, please refer to safety data sheet.6.5 ASTM D24 Standard Reference Blacks, SRB.67. Sampling7.1 Samp
23、les shall be taken in accordance with PracticesD1799 and D1900.8. Oil Absorptometers, Instrument Calibration, and End-Point Procedures8.1 Absorptometer:8.1.1 ModelThree different types of absorptometers are inuse: (1) early models based on springs and mechanical indica-tion of torque (Type A and B),
24、 (2) second generation absorp-tometers equipped with load cells and digital torque display(Type E7), and (3) current model absorptometers which aredesigned with a torque measuring system that includes amicro-computer and software to continuously record torqueand oil volume with time (Types H and C a
25、nd modified TypeE7). Types A, B, and E7are designed to stop mixing at apredetermined, fixed torque level, which is the recommendedprocedure for measuring hard or tread blacks (calibrationProcedureA). The computer controlled models (Types H and Cand modified Type E7) absorptometers can provide an end
26、-point at a fixed or predetermined torque level such that thesetypes of absorptometers are well-suited for measuring OAN ofall types of carbon blacks.8.1.2 Mixing BowlTypically the absorptometer is deliv-ered with either a surface-treated stainless steel or anodizedaluminum mixing bowl. These bowls
27、are considered accept-able provided they give the correct reading for the appropriateSRB reference standards. The surface finish of the mixerchamber is critical for maintaining proper calibration, and thebowl should not be modified to achieve calibration.NOTE 2Stainless steel chambers have been foun
28、d satisfactory for thetest when they are manufactured to a roughness value (Ra) of 2.5 60.4 m (100 6 15 in.) based upon 8 measurements. No single measure-ment should be greater than 3.6 m (140 in.) or less than 1.5 m (60in.). Stainless steel bowls purchased with an absorptometer have beenpre-polishe
29、d for 16 h to minimize bowl surface changes affectingcalibration during their initial use. It is recommended that new replace-ment stainless steel bowls should also be pre-polished in the same manner(see Annex A3).8.2 Instrument CalibrationSeveral components influencethe calibration: the dynamometer
30、 torque spring or the load cell,the torque limit switch or the indicator set point, the damper(oil damper or electronic damping), and the mixing headconsisting of two counter rotating blades and a mixing bowl. Itis necessary that all of these components are in good conditionand are properly adjusted
31、 to achieve acceptable calibration.8.2.1 Rotor BladesThe speed of the motor driving therotor blades is either fixed (Type A and B) or has to be set(Type E, C, and H) to 125 r/min. Due to a gear, one blade spinsat 125 r/min, the other blade at 250 r/min.8.2.2 Constant-Rate BuretThe delivery rate of t
32、he buret isto be 4 cm3/min. See AnnexA1 for detailed instructions on theprocedure for calibration check of the constant-rate buret.8.2.3 Spring Tension (Type A and B)It is recommendedthat the torque spring is adjusted so that the SRB F standardwill develop a maximum torque between 70 % and full-scal
33、edeflection. This is achieved by selecting the appropriate springstrength and adjusting the spring tension in accordance with theinstructions of the manufacturer.4All apparatus are to be operated and maintained in accordance with themanufacturers directions for optimum performance.5Reagent Chemicals
34、, American Chemical Society Specifications , AmericanChemical Society, Washington, DC. For suggestions on the testing of reagents notlisted by the American Chemical Society, see Analar Standards for LaboratoryChemicals, BDH Ltd., Poole, Dorset, U.K. and the United States Pharmacopeia andNational For
35、mulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville, MD.6The sole source of supply of ASTM Standard Reference Blacks known to thecommittee at this time is Laboratory Standards and Technologies, 227 Somerset,Borger, TX 79007, http:/ If you are aware of alternativesuppliers, please provide t
36、his information to ASTM International Headquarters.Your comments will receive careful consideration at a meeting of the responsibletechnical committee,1which you may attend.7Type E absorptometers can be modified with additional hardware and micro-computer system.D2414 18a2NOTE 3The absorptometers Ty
37、pe E, C, and H are calibrated by themanufacturer to give a direct reading of torque in mNm; this calibrationshould not be modified in order to achieve a desired level of torque. Ifcalibration is necessary, refer to the instrument manufacturers recommen-dations. The instrument torque calibration shou
38、ld not be confused with thetorque limit switch described in 8.3.1.8.2.4 DamperFor the Type A absorptometer, it is recom-mended to keep the valve of the oil damper fully closed. TheType B absorptometer shall provide a full-scale recovery of 36 0.5 s; the valve has to be adjusted accordingly. The Type
39、 Eabsorptometer has an electronic damping option and Types Cand H have appropriate software damping. Make sure thatthese damping options are activated.8.2.5 Stainless Mixing BowlsWhen replacing an old mix-ing bowl with a new one, further pre-polish may be neededafter installation even if those mixin
40、g bowls are typicallyalready pre-polished by the manufacturer. The surface finish ofthe mixer chamber is critical for maintaining propercalibration, and the bowl shall not be modified to achievecalibration other than described in Annex A3.8.3 End-Point Procedures:8.3.1 Torque Limit Switch (TLS) or t
41、he Indicator SetPointIf the end-point of the test is determined by a fixedtorque limit, the setting of the TLS, also called indicatorset-point, has to be selected using one of the following threeprocedures:8.3.1.1 Procedure A: End-Point at Fixed Torque LevelThis “classical” method is well suited for
42、 most hard or treadblacks but may lead to problems when low-torque carcassblacks are to be tested; proceed to Procedure B for low-torquecarbon blacks. For TypeA, B, and E absorptometers, adjust theTLS or the indicator set point in such way that the current SRBF standard gives the correct target valu
43、e within the limits asdefined in Guide D4821. For Type E, C, and H absorptometersdedicated to testing tread blacks only, there is no advantage tosetting the TLS based on the SRB F standard; for theseabsorptometers, set theTLS to 3500 mNm for DBPoil, or 4000mNm for paraffin oil.8.3.1.2 Procedure B: E
44、nd-Point at 70 % of the MaximumTorqueCertain carcass blacks and thermal blacks may fail togive an end-point due to insufficient torque level. Therefore,the preferred method for testing soft blacks is to record thetorque curve using a chart-recorder or a data acquisition systemand to read the end-poi
45、nt at 70 % of the maximum of the torqueachieved. Set the TLS or the indicator set point to full scale inorder to disable the automatic shut-off of the absorptometer.9. Normalization using Standard Reference Blacks (SRB)9.1 Physically calibrate the test apparatus including TLSadjustment using the ins
46、tructions in 8.3.9.2 Test the six ASTM Standard Reference Blacks (SRBs)in duplicate to establish the average measured value. Addi-tional values are added periodically, typically on a weeklybasis. An alternative to periodic normalizations are dailyadditions of SRB normalization tests such that the no
47、rmaliza-tion curve is continuously maintained. The rolling average ofthe measured values is computed from the latest four values.9.3 For a tread or carcass-type normalization curve, all threeSRBs should be included.9.4 For a tread or carcass-type normalization curve, all threeSRBs should be from the
48、 same series (example: series-8).Guide D4821 describes the importance of not mixing SRBseries for OAN testing.NOTE 4When only tread- or carcass-type carbon blacks are to betested, the normalization can be limited to either the three tread- (A, B, C)or the three carcass-type (D, E, F) carbon black st
49、andards.9.5 Perform a regression analysis using the standard valueof the standard (y value) and the rolling average measuredvalue (x value). Separate carcass and tread normalizationcurves should be maintained.9.6 Normalize the values of all subsequent samples usingthe regression equation as follows:Normalized value 5 measured value*slope!1intercept (1)9.7 For normalized values of the SRBs that are consistentlyoutside the x-chart limits listed in Guide D4821, the instrumentcalibration and end-point procedures in Section 8 sho
