1、Designation: D4817 88 (Reapproved 2017)Standard Classification forRubber Compounding MaterialsStearic Acid1This standard is issued under the fixed designation D4817; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last
2、revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This classification covers the compounding materialscommercially known as stearic acid.1.2 This standard does not purport t
3、o address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D1466 Te
4、st Method for Sampling Liquid Oils and FattyAcids Commonly Used in Paints, Varnishes, and RelatedMaterials (Withdrawn 2003)3D1951 Test Method for Ash in Drying Oils and Fatty Acids(Withdrawn 2003)3D1959 Test Method for Iodine Value of Drying Oils andFatty Acids (Withdrawn 2006)3D1962 Test Method for
5、 Saponification Value of Drying Oils,Fatty Acids, and Polymerized Fatty Acids (Withdrawn2004)3D1965 Test Method for Unsaponifiable Matter in DryingOils, Fatty Acids, and Polymerized Fatty Acids (With-drawn 2007)3D1980 Test Method for Acid Value of Fatty Acids andPolymerized Fatty Acids (Withdrawn 20
6、07)3D1982 Test Method for Titer of Fatty AcidsD1983 Test Method for Fatty Acid Composition by Gas-Liquid Chromatography of Methyl Esters (Withdrawn2003)3D4075 Test Methods for Rubber Compounding MaterialsFlame Atomic Absorption AnalysisDetermination ofMetals3. Significance and Use3.1 Stearic acid is
7、 important in the rubber vulcanizationprocess. It is believed that the stearic acid reacts with zinc-oxide or other metallic oxides, during vulcanization, to form arubber soluble salt or soap, that reacts with the acceleratorenabling it to exert its full effect.3.2 Stearic acid of commerce is genera
8、lly a mixture ofpalmitic, stearic, and oleic acids usually derived from tallowbase stock but can be derived from other fats and oils of animalor vegetable origins.4. Basis of Classification4.1 Classification of Stearic Acid by Classes:4.1.1 There are several different classes of stearic acid,based o
9、n stearic acid content and iodine value. There are twoclasses predominantly used in rubber compounding.4.1.1.1 Class Number 1: Stearic Acid Containing Unsatu-rated Fatty AcidsStearic acid containing unsaturated acids iscommonly referred to as rubber grade stearic acid. Threegrades are commonly avail
10、able with low, medium, and highunsaturation. These grades of stearic acid are used in rubbercompounding where unsaturated fatty acids can be tolerated.(See Table 1 for typical analysis of Class 1 stearic acid.)4.1.1.2 Class Number 2Stearic Acid with Low Levels ofUnsaturated Fatty AcidsLow IV:(1) Low
11、 iodine value stearic acid is produced in severalgrades. Two grades are commonly used in rubber compoundingwhere a 1.0 maximum iodine value is needed. These twogrades are distinguished by their ratios of palmitic to stearicacid content. The physical and chemical properties of thestearic acid will ch
12、ange as the palmitic/stearic acid ratiochanges. The palmitic/stearic ratio may be checked by TestMethod D1983. (See Table 2 for a typical analysis of the Class2 stearic acid.)(2) Stearic acid can be made to customer specifications byemploying various processing steps such as hydrogenation tolower io
13、dine value, bleaching with diatomaceous earth toimprove color and distillation, or crystallization to changechain length distribution or improve color, or both. A combi-nation of the processing steps may be used to produce the finalproduct.1This classification is under the jurisdiction of ASTM Commi
14、ttee D11 onRubber and Rubber-like Materials and is the direct responsibility of SubcommitteeD11.20 on Compounding Materials and Procedures.Current edition approved Feb. 1, 2017. Published February 2017. Originallyapproved in 1988. Last previous edition approved in 2012 as D4817 88 (2012).DOI: 10.152
15、0/D4817-88R17.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3The last approved version of this historical s
16、tandard is referenced onwww.astm.org.Copyright ASTM International, 100 Barr Harbor Drive, PO 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 P
17、rinciples for theDevelopment of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.15. Sampling5.1 Sampling to conduct tests as outlined in Section 2 shallbe carried out in accordance with Test Method D1466.ASTM Inte
18、rnational takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely
19、 their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand sho
20、uld be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Sta
21、ndards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610
22、-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org). Permission rights to photocopy the standard may also be secured from the Copyright Clearance Center, 222Rosewood Drive, Danvers, MA 01923, Tel: (978) 646-2600; http:/ 1 Typical Physical and
23、 Chemical Properties of StearicAcidClass Number 1APropertyTestMethodGrade 1Low-IVBGrade 2Med-IVBGradeHigh-IVBAsh, % D1951 0.2 max 0.2 max 0.2 maxIodine value, g/100 g D1959 8 max 15 max 39 5Saponification value,mg KOH/gD1962 204.5 5.0 204.5 5.0 .Unsaponificationmatter, %D1965 3.0 max 3.0 max .Acid v
24、alue, mg KOH/g D1980 203.5 4.5 203.0 4.5 203.5 4.5Titer, C D1982 56.0 4.5 53.0 3.0 48.5 4.5CTrace metals, ppm D4075 varies from industry to industryAThe values listed in Table 1 are typical ranges and values.BIV = iodine value.CTrace metals such as nickel, iron, copper, and manganese can be determin
25、ed inaccordance with Test Method D4075.TABLE 2 Typical Physical and Chemical Properties of StearicAcidClass Number 2AProperty Test MethodGrade 1,Palmitic/Stearic50/40BGrade 2,Palmitic/Stearic30/65Ash,% D1951 0.1 0.1Iodine, value, g/100 g D1959 1.0 max 1.0 maxSaponification value,mg KOH/gD1962 208.5
26、2.5 203.5 3.0Unsaponificationmatter, %D1965 0.2 max 0.5 maxAcid value, mg KOH/g D1980 208.5 2.0 203.0 3.0Titer, C D1982 55.5 1.0 60.0 2.0CTrace metals, ppm D4075 varies from industry to industryAThe values listed in Table 2 are typical ranges and valuesBEven though this grade contains more palmitic acid than stearic acid, this gradeis still referred to as “stearic acid” in the rubber industry.CTrace metals such as nickel, iron, copper, and manganese can be determined inaccordance with Test Method D4075.D4817 88 (2017)2
