1、Designation: D 3314 02 (Reapproved 2006)Standard Test Method forRubberChemical Analysis for Polystyrene Blocks In SBR(Styrene-Butadiene Rubber) and Styrene-ReinforcedLatices1This standard is issued under the fixed designation D 3314; the number immediately following the designation indicates the yea
2、r 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 (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method covers the determination of longpolys
3、tyrene 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-free poly-mers, but it may be used on polymers containing gel, if it hasbeen proven that gel does not interfere.1
4、.4 This 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 ha
5、zardstatements, see Section 7.2. Referenced Documents2.1 ASTM Standards:2D 1076 Specification for RubberConcentrated, AmmoniaPreserved, Creamed, and Centrifuged Natural LatexD 1416 Test Methods for Rubber from Synthetic SourcesChemical Analysis3D 4483 Practice for Evaluating Precision for Test Metho
6、dStandards in the Rubber and Carbon Black ManufacturingIndustriesE 145 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 treating a 1,2-dichlorobenzene solutio
7、n 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-molecular weight polystyrene fr
8、agments 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 polystyrene, which constitutes the ho
9、mopolymer 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 ground-glassjoint. An iodine f
10、lask 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-porosity,25 to 50-cm3size.5.9 Hot P
11、late, capable of operating to provide 120 to 130Cto boiling solution, 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 E 145.1This test method is under the jurisdiction of AS
12、TM Committee D11 on Rubberand is the direct responsibility of Subcommittee D11.11 on Chemical Analysis.Current edition approved Oct. 1, 2006. Published November 2006. Originallyapproved in 1974. Last previous edition approved in 2002 as D 3314 02.2For referenced ASTM standards, visit the ASTM websit
13、e, 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 Drive, PO Box C700, West Conshohocken, PA 19428-2959, Un
14、ited States.6. Reagents6.1 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 American Chemical Society,where such specifications are avai
15、lable.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.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 th
16、e solution from light. Decompo-sition is indicated by formation of a black precipitate. Thevapors are highly toxic. Therefore, use due precaution inreagent preparation, use, and disposal. One cubic centimetre ofthis stock solution is needed for each analysis. In view of thetoxicity of the reagent, t
17、he amount of solution prepared shouldnot greatly exceed the number of determinations to be madeover a reasonable period of time, depending 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),
18、 approximately 70 % purity assay istypical.6.7 Toluene.7. Use of Osmium Tetroxide7.1 Precautions:7.1.1 Store osmium tetroxide ampules (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, an
19、d a faceshield or goggles.7.1.3 Keep solutions of osmium tetroxide (maximum of0.5 g) in unbreakable containers and store and use in 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/m
20、in).7.1.4 Mark all containers of osmium tetroxide, whetherconcentrated or diluted with “DANGER” labels.7.1.5 Transfer all osmium tetroxide or its solutions to bedisposed of, to polyethylene bottles and incinerate. Filtrates arecollected in a dump-can set aside for chlorinated solvents, andthe conten
21、ts are also incinerated. Do not accumulate wastesolutions.7.2 Hazards:7.2.1 Osmium tetroxide is a yellow crystalline mass at roomtemperature. 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
22、derma-titis and ulceration of the skin and intense conjunctivitis andcorneal ulceration to the eye. Inhalation of osmium tetroxidemay cause capillary bronchitis and dermatitis. Even smallamounts, if inhaled over a considerable period, cause head-ache, insomnia, pharyngeal and laryngeal distress, and
23、 diges-tive disturbance. (WarningAnalysts must thoroughly famil-iarize themselves with a current Material safety data Sheet(MSDS) for osmium 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 perso
24、nnel should immediately removeto an area of fresh air. The minimum perceptible concentrationis 0.02 g/m3of air. The threshold safety limit 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
25、 kPa is 130C. However, it begins tosublime and distill well below the boiling point.8. Sampling8.1 If the sample is latex, prepare a dried film in accordancewith Specification D 1076.8.2 If the sample is an oil-extended rubber, conduct an ETAextraction in accordance with Test Methods D 1416.8.3 In a
26、ll cases, use a random unhomogenized sample.9. Procedure9.1 For a sample containing less than 30 % block styrene,cut approximately 0.5 g of 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
27、 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 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 ref
28、luxing. Separate the aircondenser from the flask, add 10 cm3of the tertiary butylhydroperoxide solution (see 6.6) and 1 cm3of the osmiumtetroxide 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 deg
29、raded in thisprocess, therefore digestion time should be constant and notlengthy.)9.4 Remove the flask from the hot plate or heating mantle.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 methan
30、ol to which 5drops of concentrated H2SO4has 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 “police-man,” the precipitated polystyrene to a tared, medium-frittedGooch crucible.
31、 Wash the precipitated polystyrene copiouslywith methanol to remove all the 1,2-dichlorobenzene, then with100 cm3of hot water to remove surfactants and electrolytes.Finally, wash with 100 cm3of methanol again.9.6 Dry the precipitate for2hat100C, cool in a desiccator,and weigh.4Reagent Chemicals, Ame
32、rican 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 Formular
33、y, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville,MD.D 3314 02 (2006)210. Calculation10.1 Calculate the percent block styrene as follows:Block styrene, % 5 WA2 WB!/WC# 3 100 (1)where:WA= mass of crucible + polystyrene precipitate, g,WB= mass of crucible, g, andWC= mass of sample, g.10.2 A tes
34、t result is the average of two test determinations.11. Precision and Bias511.1 This precision and bias section has been prepared inaccordance with Practice D 4483. Refer to Practice D 4483 forterminology and other statistical calculation details.11.2 A Type 1 (interlaboratory) precision was evaluate
35、d.Both repeatability and reproducibility are short term, a periodof a few days separates replicate test results. A test result is theaverage value as specified by this test method, obtained on twodeterminations or measurements of the property or parameterin question.11.3 Five different materials wer
36、e used in the interlabora-tory program, these were tested in two laboratories on fourdifferent days.11.4 The results of the precision calculations 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 Th
37、e precision of this test method may be expressed inthe format of the following statements which use what is calledan “appropriate value” of r, R,(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 Ras
38、sociated with a mean level in Table 1 closest to the meanlevel under consideration at any given time, for any givenmaterial in routine testing operations.11.6 RepeatabilityThe repeatability, r, of this test methodhas been established as the appropriate value for any parametertabulated in Table 1. Tw
39、o single test results, obtained undernormal test method procedures, that differ by more than thistabulated r (for any given level) must be considered as derivedfrom different or nonidentical sample populations.11.7 ReproducibilityThe reproducibility, R, of this testmethod has been established as the
40、 appropriate value tabulatedin Table 1. Two single test results obtained in two differentlaboratories, under normal test method procedures, that differby more than the tabulated R (for any given level) must beconsidered to have come from different or nonidentical samplepopulations.11.8 Repeatability
41、 and reproducibility expressed as a per-centage of the mean level, (r) and (R), have equivalentapplication statements as above for r and R. For the (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 Bias
42、In test method terminology, bias is the differ-ence between an average test value and the reference (or true)test property value. Reference values do not exist for this testmethod since the value (of the test property) is exclusivelydefined by the test method. Bias, therefore, cannot be deter-mined.
43、12. Keywords12.1 polystyrene; SBR; styrene-butadiene rubber5Supporting data have been filed at ASTM International Headquarters and maybe obtained by requesting Research Report RR: D11-1001.TABLE 1 Type 1 PrecisionNOTESr= within laboratory standard deviation.r = repeatability (in measurement units).(
44、r) = repeatability (in percent).SR= between laboratory standard.R = reproducibility (in measurement units).(R) = reproducibility (in percent).Material 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 1
45、6.54 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 this test method a percent of a percentage.D 3314 02 (2006)3ASTM International takes no position respecting the validity of any patent rights asserted in c
46、onnection 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 their own responsibility.This standard is subject to revision at any time by the resp
47、onsible 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 carefu
48、l 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 Standards, at the address shown below.This standard is copyrighted by ASTM International,
49、 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 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).D 3314 02 (2006)4
