1、Designation: D3314 02 (Reapproved 2017)Standard Test Method forRubberChemical Analysis for Polystyrene Blocks In SBR(Styrene-Butadiene Rubber) and Styrene-ReinforcedLatices1This standard is issued under the fixed designation D3314; the number immediately following the designation indicates the year
2、oforiginal adoption or, in the case of revision, the year of last 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 test method covers the determination of longpolystyr
3、ene blocks in SBR rubbers and styrene-reinforcedlatices.1.2 Percent block styrene content may be determined in therange from 1 to 100 %.1.3 This test method is intended for use on gel-freepolymers, but it may be used on polymers containing gel, if ithas been proven that gel does not interfere.1.4 Th
4、is standard does not purport to 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. For specific hazards
5、tatements, see Section 7.1.5 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recom-mendations issued by the World Trade Organiza
6、tion TechnicalBarriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2D1076 Specification for RubberConcentrated, AmmoniaPreserved, Creamed, and Centrifuged Natural LatexD1416 Test Methods for Rubber from Synthetic SourcesChemical Analysis (Withdrawn 1996)3D4483 Practice for Eva
7、luating Precision for Test MethodStandards in the Rubber and Carbon Black ManufacturingIndustriesE145 Specification for Gravity-Convection and Forced-Ventilation Ovens3. Summary of Test Method3.1 The test method is based upon oxidative cleavage of theethylenic bonds in the block copolymer by treatin
8、g a 1,2-dichlorobenzene solution of the polymer with tertiary butylhydroperoxide (2-methyl-2-hydroperoxypropane) with os-mium tetroxide catalyst. The saturated portions of the polymer,which contain no ethylenic bonds, remain unattacked. Thesmall fragments (low molecular weight aldehydes) and thelow-
9、molecular weight polystyrene fragments from scissionswithin the random copolymer block are soluble in methylalcohol, whereas the detached high-molecular weight polysty-rene from the styrene homopolymer block is insoluble inalcohol. It is therefore possible to separate the high-molecularweight polyst
10、yrene, which constitutes the homopolymer block,from the polymer solution.4. Significance and Use4.1 This test method is suitable for manufacturing control,development, and research studies.5. Apparatus5.1 Erlenmeyer Flask, or round-bottom flask for use withthe heating mantle, of 250-cm3capacity with
11、 ground-glassjoint. An iodine flask is also satisfactory.5.2 Air Condenser, for 5.1.5.3 Beaker, 600-cm3.5.4 Graduated Cylinder, 50-cm3.5.5 Pipet, 1-cm3.5.6 Buret, 100-cm3, for dispensing tertiary butyl hydroper-oxide.5.7 Thermometer, to 150C range.5.8 Crucible, Gooch-type, fritted-glass, medium-poro
12、sity,25 to 50-cm3size.1This test method is under the jurisdiction of ASTM Committee D11 on Rubberand Rubber-like Materials and is the direct responsibility of Subcommittee D11.11on Chemical Analysis.Current edition approved May 1, 2017. Published May 2017. Originallyapproved in 1974. Last previous e
13、dition approved in 2012 as D3314 02 (2012).DOI: 10.1520/D3314-02R17.2For 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 w
14、ebsite.3The last approved version of this historical standard 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 principl
15、es on standardization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.15.9 Hot Plate, capable of operating to provide 120 to 130Cto boiling solution,
16、 or heating mantle for round-bottom flasksoperating in the same temperature range.5.10 Drying Oven, capable of controlling at 100C Type 1Boven in accordance with Specification E145.6. Reagents6.1 Purity of ReagentsReagent grade chemicals shall beused in all tests. Unless otherwise indicated, it is i
17、ntended thatall reagents shall conform to the specifications of the Commit-tee on Analytical Reagents of the American 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 w
18、ithout lessening theaccuracy of the determination.6.2 1,2-Dichlorobenzene.6.3 Methanol.6.4 Osmium Tetroxide (0.004 M Solution in Toluene 1 kg/m3(0.1 g/100 cm3)Protect the solution from light. Decomposi-tion is indicated by formation of a black precipitate. The vaporsare highly toxic. Therefore, use
19、due precaution in reagentpreparation, use, and disposal. One cubic centimetre of thisstock solution is needed for each analysis. In view of thetoxicity of the reagent, the amount of solution prepared shouldnot greatly exceed the number of determinations to be madeover a reasonable period of time, de
20、pending on the stability ofthe solution and the work load.6.5 Sulfuric Acid (density 1.84 Mg/m3)(H2SO4).6.6 Tertiary Butyl Hydroperoxide (2-Methyl-2-Hydroperoxypropane), approximately 70 % purity assay istypical.6.7 Toluene.7. Use of Osmium Tetroxide7.1 Precautions:7.1.1 Store osmium tetroxide ampul
21、es (maximum total of3 g) inside capped pipe or its equivalent.7.1.2 Persons working with osmium tetroxide or its solu-tions should wear rubber gloves, a rubber apron, and a faceshield or goggles.7.1.3 Keep solutions of osmium tetroxide (maximum of0.5 g) in unbreakable containers and store and use in
22、 the hood.The volume of air mechanically exhausted should be such thatthe hood-face velocities are within acceptable limits (a recom-mended minimum of (0.5 m/s) 100 ft/min).7.1.4 Mark all containers of osmium tetroxide, whetherconcentrated or diluted with “DANGER” labels.7.1.5 Transfer all osmium te
23、troxide or its solutions to bedisposed of, to polyethylene bottles and incinerate. Filtrates arecollected in a dump-can set aside for chlorinated solvents, andthe contents are also incinerated. Do not accumulate wastesolutions.7.2 Hazards:7.2.1 Osmium tetroxide is a yellow crystalline mass at roomte
24、mperature. It can be hazardous in either its crystalline orvapor form. On contact with the skin or eyes, it producesirritation and if not removed immediately, may cause derma-titis and ulceration of the skin and intense conjunctivitis andcorneal ulceration to the eye. Inhalation of osmium tetroxidem
25、ay cause capillary bronchitis and dermatitis. Even smallamounts, if inhaled over a considerable period, causeheadache, insomnia, pharyngeal and laryngeal distress, anddigestive disturbance. (WarningAnalysts must thoroughlyfamiliarize themselves with a current Material safety dataSheet (MSDS) for osm
26、ium tetroxide.)7.2.2 The vapor has a pronounced acrid, chlorine-like odor,which should be taken as a warning of the toxic concentrationin the atmosphere, and personnel should immediately removeto an area of fresh air. The minimum perceptible concentrationis 0.02 g/m3of air. The threshold safety limi
27、t is 0.002 mg/m3of air. Therefore, it cannot be detected by odor at the thresholdsafety limit. The melting point of the crystals is 56C and theboiling point at 100 kPa is 130C. However, it begins tosublime and distill well below the boiling point.8. Sampling8.1 If the sample is latex, prepare a drie
28、d film in accordancewith Specification D1076.8.2 If the sample is an oil-extended rubber, conduct an ETAextraction in accordance with Test Methods D1416.8.3 In all cases, use a random unhomogenized sample.9. Procedure9.1 For a sample containing less than 30 % block styrene,cut approximately 0.5 g of
29、 rubber weighed to the nearest0.1 mg into small pieces. Add the pieces to a 250-cm3Erlenmeyer flask (or round-bottom flask), to which 35 cm3of1,2-dichlorobenzene has been previously added. For rubberscontaining more than 30 % block styrene, use a 0.3-g speci-men.9.2 Fit an air condenser to the flask
30、 and heat it and itscontents to 120 6 5C, until the rubber dissolves.9.3 Remove the flask from the hot plate or heating mantleand cool it just enough to stop refluxing. Separate the aircondenser from the flask, add 10 cm3of the tertiary butylhydroperoxide solution (see 6.6) and 1 cm3of the osmiumtet
31、roxide solution (see 6.4). Replace the air condenser andcontinue heating the resulting solution at 100 to 120C for 12to 15 min. (Polystyrene is itself slowly degraded in thisprocess, therefore digestion time should be constant and notlengthy.)9.4 Remove the flask from the hot plate or heating mantle
32、.When it has cooled so that it can be held without discomfort,pour the solution slowly and with constant stirring into a600-cm3beaker containing 350 cm3of methanol to which 54Reagent Chemicals, American Chemical Society Specifications, AmericanChemical Society, Washington, DC. For Suggestions on the
33、 testing of reagents notlisted by the American Chemical Society, see Annual Standards for LaboratoryChemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeiaand National Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville,MD.D3314 02 (2017)2drops of concentrated H2SO4
34、has been added. Agitate theresulting mixture with a magnetic stirrer for 1 to 2 h, toflocculate the insoluble polystyrene.9.5 Quantitatively transfer, with the aid of a rubber“policeman,” the precipitated polystyrene to a tared, medium-fritted Gooch crucible. Wash the precipitated polystyrenecopious
35、ly with methanol to remove all the 1,2-dichlorobenzene, then with 100 cm3of hot water to removesurfactants and electrolytes. Finally, wash with 100 cm3ofmethanol again.9.6 Dry the precipitate for2hat100C, cool in a desiccator,and weigh.10. Calculation10.1 Calculate the percent block styrene as follo
36、ws:Block styrene, % 5WA2 WB!/WC#3100 (1)where:WA= mass of crucible + polystyrene precipitate, g,WB= mass of crucible, g, andWC= mass of sample, g.10.2 A test result is the average of two test determinations.11. Precision and Bias511.1 This precision and bias section has been prepared inaccordance wi
37、th Practice D4483. Refer to Practice D4483 forterminology and other statistical calculation details.11.2 A Type 1 (interlaboratory) precision was evaluated.Both repeatability and reproducibility are short term, a periodof a few days separates replicate test results. A test result is theaverage value
38、 as specified by this test method, obtained on twodeterminations or measurements of the property or parameterin question.11.3 Five different materials were used in the interlabora-tory program, these were tested in two laboratories on fourdifferent days.11.4 The results of the precision calculations
39、 for repeatabil-ity and reproducibility are given in Table 1, in ascending orderof material average or level, for each of the materials evalu-ated.11.5 The precision of this test method may be expressed inthe format of the following statements which use what is calledan “appropriate value” of r, R,(
40、r), or (R), that is, that value tobe used in decisions about test results (obtained with this testmethod). The appropriate value is that value of r or Rassociated with a mean level in Table 1 closest to the meanlevel under consideration at any given time, for any givenmaterial in routine testing ope
41、rations.11.6 RepeatabilityThe repeatability, r, of this test methodhas been established as the appropriate value for any parametertabulated in Table 1. Two single test results, obtained undernormal test method procedures, that differ by more than thistabulated r (for any given level) must be conside
42、red as derivedfrom different or nonidentical sample populations.11.7 ReproducibilityThe reproducibility, R, of this testmethod has been established as the appropriate value tabulatedin Table 1. Two single test results obtained in two differentlaboratories, under normal test method procedures, that d
43、ifferby more than the tabulated R (for any given level) must beconsidered to have come from different or nonidentical samplepopulations.11.8 Repeatability and reproducibility expressed as a per-centage of the mean level, (r) and (R), have equivalentapplication statements as above for r and R. For th
44、e (r) and (R)statements, the difference in the two single test results isexpressed as a percentage of the arithmetic mean of the two testresults.11.9 BiasIn test method terminology, bias is the differencebetween an average test value and the reference (or true) testproperty value. Reference values d
45、o not exist for this testmethod since the value (of the test property) is exclusivelydefined by the test method. Bias, therefore, cannot be deter-mined.12. Keywords12.1 polystyrene; SBR; styrene-butadiene rubber5Supporting data have been filed at ASTM International Headquarters and maybe obtained by
46、 requesting Research Report RR:D11-1001.TABLE 1 Type 1 PrecisionNOTE 1Sr= within laboratory standard deviation.r = repeatability (in measurement units).(r) = repeatability (in percent).SR= between laboratory standard.R = reproducibility (in measurement units).(R) = reproducibility (in percent).Mater
47、ial Mean Value, %Within Laboratories Between LaboratoriesSrr (r)ASRR (R)A1 2.85 0.509 1.44 50.5 0.320 0.906 31.72 5.03 0.498 1.41 28.0 0.553 1.56 31.03 16.54 0.650 1.84 11.1 0.720 2.04 12.44 29.81 0.707 2.00 6.71 0.550 1.56 5.25 37.78 1.64 4.64 12.3 2.75 7.78 20.6ARelative precision, that is, for th
48、is test method a percent of a percentage.D3314 02 (2017)3ASTM International 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 paten
49、t rights, and the riskof infringement of such rights, are entirely 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 should 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 c
