1、Designation: D 297 93 (Reapproved 2006)Standard Test Methods forRubber ProductsChemical Analysis1This standard is issued under the fixed designation D 297; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision.
2、A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defense.1. Scope1.1 These test methods cover the qualitative and quanti
3、ta-tive analysis of the composition of rubber products of the “R”family (see 3.1). Many of these test methods may be applied tothe analysis of natural and synthetic crude rubbers.1.1.1 Part A consists of general test methods for use in thedetermination of some or all of the major constituents of aru
4、bber product.1.1.2 Part B covers the determination of specific polymerspresent in a rubber product.1.1.3 The test methods appear in the following order:Part A. General Test Methods: SectionsRubber Polymer Content by the Indirect Method 11-13Determinations and Report for the General Method 14 and 15D
5、ensity 16Extract Analysis 17-26Sulfur Analysis 27-33Fillers Analysis 34-40Ash Analysis 41-51Part B. Determination of Rubber Polymers 52-581.2 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
6、 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. Specific precau-tionary or warning statements are g
7、iven in 31.4.5, 31.6, 37.4.2,38.4.2, 45.1.3, 53.2.3.5, 54.4.2, 54.6, 56.5.3, and 57.7.3; andX1.3.3 and X2.4.1.6.2. Referenced Documents2.1 ASTM Standards:2D 982 Method of Test for Organic Nitrogen in Paper andPaperboard3D 1416 Test Methods for Rubber from Synthetic Sources-Chemical Analysis3D 1418 P
8、ractice for Rubber and Rubber LaticesNomenclatureD 1646 Test Methods for RubberViscosity, Stress Relax-ation, and Pre-Vulcanization Characteristics (Mooney Vis-cometer)D 3040 Practice for Preparing Precision Statements forStandards Related to Rubber and Rubber Testing3D 3156 Practice for RubberChrom
9、atographic Analysis ofAntidegradants (Antioxidants, Antiozonants and Stabiliz-ers)D 3452 Practice for RubberIdentification by Pyrolysis-Gas ChromatographyD 3677 Test Methods for RubberIdentification by Infra-red SpectrophotometryD 4483 Practice for Evaluating Precision for Test MethodStandards in th
10、e Rubber and Carbon Black ManufacturingIndustriesE11 Specification for Wire Cloth and Sieves for TestingPurposesE 131 Terminology Relating to Molecular SpectroscopyE 200 Practice for Preparation, Standardization, and Stor-age of Standard and Reagent Solutions for ChemicalAnalysisE 442 Test Method fo
11、r Chlorine, Bromine, or Iodine inOrganic Compounds by Oxygen Flask Combustion3E 443 Test Method for Sulphur in Organic Compounds byOxygen Flask Combustion33. Terminology3.1 DefinitionsThe nomenclature and abbreviations usedfor natural and synthetic rubbers are in accordance withPractice D 1418.1Thes
12、e test methods are under the jurisdiction of ASTM Committee D11 onRubber and are the direct responsibility of Subcommittee D11.11 on ChemicalAnalysis.Current edition approved Oct. 1, 2006. Published November 2006. Originallyapproved in 1928. Last previous edition approved in 2002 as D 297 93 (2002).
13、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.3Withdrawn.1Copyright ASTM International, 100 Barr Harbor Dri
14、ve, PO Box C700, West Conshohocken, PA 19428-2959, United States.4. Reagents4.1 Purity of ReagentsReagent grade chemicals shall beused in all tests. Unless otherwise indicated, it is intended thatall reagents shall conform to the specifications of the Commit-tee on Analytical Reagents of the America
15、n Chemical Society,where such specifications are available.4Other grades may beused, provided it is first ascertained that the reagent is ofsufficiently high purity to permit its use without lessening theaccuracy of the determination.4.2 Purity of WaterUnless otherwise indicated, referencesto water
16、shall be understood to mean distilled water or water ofequal purity.5. Concentration of Reagents5.1 Concentrated Acids and Ammonium HydroxideWhenacids and ammonium hydroxide are specified by name orchemical formula only, it is understood that concentratedreagents of the following densities or concen
17、trations areintended:Density,Mg/m3Acetic acid, HC2H3O2(99.7 %) 1.05Formic acid, HCOOH 1.22Hydrochloric acid, HCl 1.19Hydrofluoric acid, HF (49 %) 1.16Nitric acid, HNO31.42Phosphoric acid, H3PO4(85 %) 1.70Sulfuric acid, H2SO41.84Ammonium hydroxide, NH4OH 0.90The desired densities or concentrations of
18、 all other concen-trated acids are stated whenever they are specified.5.2 Diluted Acids and Ammonium HydroxideConcentrations of diluted acids and ammonium hydroxide,except when standardized, are specified as a ratio stating thenumber of volumes of the concentrated reagent to be added toa given numbe
19、r of volumes of water, as in the followingexample: HCl (1 + 9) means 1 volume of concentrated HCl(density 1.19) mixed with 9 volumes of water. Acids shall beadded to water slowly, with stirring.5.3 Standard SolutionsConcentrations of standard solu-tions are expressed as normalities or as volume of s
20、olution thatreacts with or contains a given mass of material being used ordetermined, for example: 0.1 N Na2S2O3solution, or CuSO4solution (1 cm3= 0.001 g Cu).5.4 Nonstandardized SolutionsConcentrations of non-standardized solutions prepared by dissolving a given mass ina solvent are specified in gr
21、ams of the reagent (as weightedout)/dm3of solution, and it is understood that water is thesolvent unless otherwise specified, for example: NaOH (10g/dm3) means 10 g of NaOH dissolved in water and dilutedwith water to 1 dm3(Note 1). In the case of certain reagents theconcentration may be specified as
22、 a percentage by mass, forexample: ethanol (50 %) means a solution containing 50 g ofethanol per 100 g of solution. Other nonstandardized solutionsmay be specified by name only, and the concentration of suchsolutions will be governed by the instructions for their prepa-ration.NOTE 1Whenever a hydrat
23、ed salt is used in the preparation of areagent (for example, BaCl22H2O) the preparation of the reagent isdescribed in detail. When an anhydrous salt is used in preparing a simpleaqueous solution the reagent is listed by title only and details of thepreparation are not given.PART A. GENERAL TEST METH
24、ODS6. Scope and Application6.1 The general test methods described cover the analysis ofmany types of rubber products to determine the amount andtype of nonrubber constituents and to calculate indirectly fromthese data the amount of rubber constituent.6.2 The applications and limitations of the test
25、methods toanalysis of specific types of rubber products are given in thescopes of the various test methods. Application to types ofrubber products not specified in the scope of a particular testmethod shall be verified by application to a control of knownand similar composition.6.3 Special test meth
26、ods for analysis are given for rubberproducts containing glue, free carbon, antimony, lead, mineraloil, waxy hydrocarbons, and barium carbonate.6.4 For the determination of the amount of a rubber polymerpresent in a rubber product, an indirect test method is given bywhich the nonrubber constituents
27、are determined individuallyor in groups, and the rubber polymer content is determined bydifference (Sections 11-13). If, in using this test method, fillersare determined by the ashing test method (Section 35 or 36),satisfactory results will be obtained, except where there arefound to be present deco
28、mposable compounding ingredientssuch as carbonates that decompose at 550C, clay, asbestine,talc, hydrated silica, antimony sulfide, halogen-containingcomponents, and silicone polymers. No test method of fillerdetermination herein described will give accurate results in thepresence of clay, silica, t
29、alc, or any other hydrated filler unlessa correction can be made for losses of water of hydration onashing. This correction can be made only if the nature andquantity of these fillers are known. The indirect test methodwill not give accurate results in the presence of halogen-containing components o
30、r silicone rubber. In the presence ofantimony sulfide or carbonates decomposing at 550C, but inthe absence of the above interfering constituents, approximatecorrection can be made by means of determination of totalantimony (Section 50) or of the metal associated with the4Reagent Chemicals, American
31、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 Pharmacopeiaand National Formulary, U.
32、S. Pharmaceutical Convention, Inc. (USPC), Rockville,MD.D 297 93 (2006)2decomposable carbonate (usually calcium, Section 45)or(Section 49) and calculation of the original composition of thecompounding ingredient from these data.6.5 If factice or high percentages of mineral rubber arepresent, no accu
33、rate test method is known for determination ofrubber content or for complete analysis of the rubber product.6.6 For the determination of the rubber content of hardrubber products, no accurate test method is described herein iffillers decomposable at 550C are present.7. Blank Determinations7.1 Blanks
34、 shall be run on all determinations to check thepurity of the materials used and deductions shall be madeaccordingly.8. Check Analyses8.1 Duplicate determinations shall be made and shall checkwithin the limits specified in the test method, when these arestated.9. Preparation of Samples9.1 Before pre
35、paring a sample for analysis, the analyst shall,by inspection, assure himself that it has not been contaminated.The sample to be analyzed shall be selected by taking piecesfrom various parts of the original sample and separating themfrom foreign matter. Because of the variety of rubber productsto wh
36、ich this test method can be applied, no single procedurefor reducing the sample to the required fineness is applicable toall samples. Therefore, several alternative procedures for thispurpose are described in 9.2 to 9.7. The analyst is expected toselect the one most suitable to the sample that he is
37、 analyzingand the equipment available.9.2 For vulcanized soft rubber, unvulcanized rubber, cruderubber, and many samples of reclaimed rubber, it is preferableto mix the sample and grind it by passing it two or three timesthrough a clean, cold, laboratory rubber mill. The rubber willcome from the mil
38、l in the form of a coarse powder or a roughsheet. If the product is in the form of a sheet, the adjustment ofthe mill shall be such that the thickness of the final sheet is nogreater than 0.5 mm. If the sample is sticky, it shall be rolledin a liner material that will not adhere to or contaminate th
39、esample. If the milled sample is a powder, it shall be transferredto a No. 14 (1.40-mm) sieve5and rubbed through the sieve.Grinding shall be continued until the entire sample passesthrough the sieve.9.3 In the absence of milling machinery, the sample may beprepared by cutting it with scissors so tha
40、t it will pass a No. 14(1.40-mm) sieve.6,7The sample may be cut into long strips thatare fine enough to pass freely through the sieve and the stripsfed through by hand, or the sample may be cut into smallfragments and shaken through the sieve. The cutting shall becontinued until the entire sample pa
41、sses through the sieve. Ifnecessary, to prevent sticking, different fragments of the sievedsample may be segregated by wrapping in a liner material thatwill not adhere to or contaminate the sample.9.4 Certain very glutinous samples may be prepared forextraction analysis as follows: Place a weighed 2
42、-g sample ofthe material between two pieces of ashless filter paper that hasbeen extracted in accordance with Section 21. The papersshould be approximately 500 by 100 mm (20 by 4 in.) and thesample should be placed near one end. Flatten the sample andspread it throughout the length of the filter pap
43、er by passing the“sandwich” lengthwise, through a cold, closely set, even-speedrubber calender. The gross thickness of the resulting sheetshould not be greater than 1.0 mm. If a rubber calender is notavailable, a similar sheet may be obtained by placing thesample in a hydraulic press or a vise. In t
44、he latter case, thesample may be roughly spread by hand throughout the lengthof the filter paper and pressure applied to small areas at a timeuntil the whole sample has been flattened.9.5 Samples of rubberized cloth, whose overall thickness isno greater than 1.0 mm, may be prepared for analysis bycu
45、tting them into pieces 1.5 mm square and then mixing well.If the fabric is easily removed, it should be separated, unless ananalysis of the whole cloth is desired.9.6 Samples of rubber cements shall be evaporated todryness in a vacuum oven at a temperature not higher than30C. The residue may then be
46、 analyzed as an unvulcanizedsample. A separate sample of the cement shall be distilledunder reduced pressure if examination of the solvent is desired.9.7 Samples of hard rubber shall be reduced to powder formby filing, cleaned with a magnet, and sieved through a No. 30(600-m) sieve.6Residue retained
47、 on this sieve shall bereduced until the entire sample passes through the sieve.10. Preliminary Examination of Samples10.1 The procedures given in 10.1.1-10.1.9 are for use indetermining the number and kind of tests that should beconducted to obtain the desired information concerning therubber produ
48、ct.10.1.1 CarbonatesDrop a small piece of sample into atest tube containing HCl saturated with bromine. If a stream ofbubbles is given off, carbonates are present. The test is notapplicable to IIR products.10.1.2 Antimony and LeadAsh a 0.2 to 0.3-g specimen inaccordance with 35.4 or 36.4. Dissolve t
49、he ash in 10 cm3ofHCl by heating. Dilute to about 40 cm3and decant or filter thesolution from the residue. Pass H2S into the solution. If ared-orange precipitate forms, antimony is present and may bedetermined on a rubber specimen in accordance with Section50. Organic sulfur shall be determined in accordance with 27.3.Dilute with water to about 400 cm3and again pass in H2S. Ifa black precipitate appears, lead is present and organic andinorganic sulfur shall be determined in accordance with 28.3and 28.4.10.1.3 Carbon BlackHeat a portion of the sample withHNO3un
