1、Designation: D4026 06 (Reapproved 2017)Standard Test Method forRubber LatexStyrene-Butadiene CopolymerDetermination of Residual Styrene1This standard is issued under the fixed designation D4026; the number immediately following the designation indicates the year oforiginal adoption or, in the case o
2、f 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 the re-sidual styrene content of styrene butadien
3、e (SBR) latex. Thistest method is based upon direct injection of a diluted latex intoa gas chromatograph. The amount of residual styrene iscalculated using an internal standard technique.1.2 The range of residual styrene covered is approximately100 to 3000 mg/kg (ppm) with a lower detection limit of
4、approximately 50 mg/kg (ppm).1.3 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.1.4 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of th
5、is standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use. (For specific safetystatements, see Section 8.)1.5 This international standard was developed in accor-dance with internationally recognized principles on standar
6、d-ization established in the Decision 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:2D4483 Practice for Evaluating Precision for Test
7、 MethodStandards in the Rubber and Carbon Black ManufacturingIndustriesE11 Specification for Woven Wire Test Sieve Cloth and TestSievesE260 Practice for Packed Column Gas ChromatographyE355 Practice for Gas Chromatography Terms and Relation-ships3. Summary of Test Method3.1 A sample of latex is mixe
8、d with a wetting agent and aninternal standard of vinyl toluene. It is then injected into a gaschromatograph equipped with a flame ionization detector. Theamount of residual styrene is determined by the internalstandard technique.4. Significance and Use4.1 The amount of residual styrene (unreacted s
9、tyrene) in anSBR latex must be studied from health, safety, economic, andenvironment viewpoints. This test method is useful in studyingthese aspects of residual styrene and also in research,development, and factory processing problems.5. Interferences5.1 Materials that interfere with the complete se
10、paration ofstyrene and vinyl toluene must be absent. Matrix effects(anything in the latex that affects the release of styrene or vinyltoluene, or both) may be minimized by the use of an additiontechnique.6. Apparatus6.1 Gas Chromatograph:6.1.1 Any gas chromatograph whose operating parametersand colu
11、mns provide well-resolved, narrow, styrene and vinyltoluene peaks, free of interference, may be used. The chro-matograph must be equipped with a flame ionization detector(FID) and preferably with some means of electronic ormicroprocessor type of integration. Detectors must be operatedin the 200 to 3
12、00C range and injection ports must be operatedin the 200 to 210C range.NOTE 1It is understood that the gas chromatograph will be operatedin accordance with the manufacturers instructions for optimum perfor-mance and that the equipment will be operated by persons knowledgeablein the techniques of gas
13、 chromatography. Practice E260 and PracticeE355, manufacturers literature, and standard texts on gas chromatographyare especially helpful.6.1.2 Equip the chromatograph with removable glass linersfor easy cleaning. Cleaning will be required when spurious1This test method is under the jurisdiction of
14、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 1981. Last previous edition approved in 2012 as D4026 06 (2012).DOI: 10.1520/D4026-06R17.2
15、For 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.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C7
16、00, 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 by the W
17、orld Trade Organization Technical Barriers to Trade (TBT) Committee.1peaks begin to appear and usually after about 20 injections. Ifglass liners are not available, metal liners, packed with glasswool, may be used.6.2 Gas Chromatographic Columns, Packings, andProgramsAny column, packing, or program l
18、isted in Table 1is satisfactory, as long as it produces narrow, well-resolvedstyrene and vinyl toluene peaks. Other columns, packings, andprograms may be used, as long as they satisfy these require-ments.6.3 Syringes, capable of delivering 1 mm3(1L).NOTE 2Syringes may be cleaned by drawing water int
19、o the syringebarrel, then ejecting it, while heating the syringe needle with a smallflame.6.4 Pipets, capable of accurately delivering 0.1 cm3.6.5 Glass Vials, of 20-cm3capacity, equipped with self-sealing septa.6.6 Analytical Balance, capable of weighing to 60.1 mg.6.7 Ordinary Laboratory Glassware
20、, necessary for carryingout this procedure.6.8 Mechanical Shaker, that will accept the vials of 6.5.(Desirable, but not mandatory.)7. Reagents and Materials7.1 Deionized Water or equivalent.7.2 Nonionic Wetting Agent (isooctyl phenyl polyethoxyethanol).37.3 Styrene (p-tert butyl catechol, inhibited)
21、There shall beno chromatographic peaks that interfere with vinyl toluene andit shall show no turbidity when mixed with methanol.7.4 Vinyl Toluene (polymerization grade28 % p-vinyltoluene and 72 % m-vinyl toluene) and pure o-vinyl toluene.Both chemicals elute from the chromatograph as one sharppeak a
22、nd have the same response to the FID. Neither of thesechemicals shall show turbidity when mixed with methanol.8. Safety Precautions8.1 Special care should be exercised in the use of com-pressed gases required for the operation of the gas chromato-graph. Styrene and vinyl toluene should be handled in
23、 well-ventilated areas or in fume hoods, to minimize health andsafety hazards.9. Sampling and Selection of Test Portions9.1 Since the use of this test method may be required for anypurpose listed under Section 4, the analyst may choose the3The sole source of supply of nonionic wetting agent (Triton
24、X100) known to thecommittee at this time is Rohm and Haas, Philadelphia, PA 19105. If you are awareof alternative suppliers, please provide this information to ASTM InternationalHeadquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee,1which y
25、ou may attend.TABLE 1 Parameters for the Gas ChromatographNOTE 1Packings and supports may also be obtained from most companies that supply gas chromatographic supplies and equipment.Chromatograph AB C D EColumn:Glass X XStainless steel X X XLength, cm 300 300 300 180 150Outside diameter, mm 6 3 3 3
26、6Inside diameter, mm 2 2Packed with 20 % SP 2100A,BorOV-101/0.1 %C,BCarbowax 1500D, B20 % SP 2100orOV-101/0.1 %Carbowax 150010 % OV 225C,B10 % Apiezon LE,B5 % SP 1200/1.7 % Bentone 34F,BSupport type SupelcoportA,BSupelcoport (1) ChromosorbW-HPG,B(2) ChromosorbP-NAWG,BChromosorb W SupelcoportMesh siz
27、e, mH150/125 150/125 (1) 150/125(2) 180/150180/150 125Carrier gas helium helium helium helium heliumCarrier gas flow, cm3/min30 30 15 30 Detector, C 250 250 250 200 300Program:Initial, C 8090 8090 50 85Initial time, min 5 5 2 19Rate, C 8 8 16 50Final, C 120 120 135 150 165Isothermal No No Yes No NoA
28、The sole source of supply of the apparatus (SP 2100 and Supelcoport) known to the committee at this time is Supelco, Inc., Supelco Park, Bellefonte, PA 16823.BIf you are aware of alternative suppliers, please provide this information to ASTM International Headquarters. Your comments will receive car
29、eful consideration at ameeting of the responsible technical committee,1which you may attend.CThe sole source of supply of the apparatus (OV-101 and 225) known to the committee at this time is Pierce Chemical Co., P.O. Box 117, Rockford, IL 61105.DThe sole source of supply of the apparatus (Carbowax
30、1500) known to the committee at this time is Union Carbide Corp., 270 Park Ave., New York, NY 10017.EThe sole source of supply of the apparatus (Apiezon L) known to the committee at this time is the James G. Biddle Co., Township Line Sieve designations: No. 80 180 m, No. 100 150 m, No. 120 125 m.D40
31、26 06 (2017)2sample and test portion at his discretion. A necessary require-ment is that the test portion be as representative of the sampleas possible.10. Calibration10.1 For a series of analyses, sufficient stock and calibrationsolutions are made prior to test portion preparation. Theconcentration
32、s of these solutions are tabulated as follows, butmay be different if the analyst so chooses. In any case, theexact concentrations of styrene and vinyl toluene must beknown.10.2 Stock Solutions:10.2.1 Stock Solution ADissolve 20 g of nonionic wettingagent (7.2) in 180 g of water (7.1).10.2.2 Stock S
33、olution BWeigh approximately 250 6 0.1mg of styrene (7.3) into a 50-cm3volumetric flask and dilute tothe mark with Stock Solution A (10.2.1).10.2.3 Stock Solution CWeigh approximately 150 60.1 mg of vinyl toluene (7.4) into a 50-cm3volumetric flaskand dilute to the mark with Stock Solution A (10.2.1
34、).NOTE 3In the subsequent analyses, if the addition of Stock SolutionA coagulates the latex, do not use. Substitute an equivalent volume ofwater (7.1). The use of this wetting agent is especially helpful in reducingplugging of the syringe needles and aids in the homogeneous dispersion ofadded styren
35、e and vinyl toluene.10.3 Calibration MixturesTo each of four bottles, add5cm3of water (7.1),5cm3of Stock Solution A (10.2.1).Proceed as follows:10.3.1 Label one bottle, D, and add 0.1 cm3of StockSolution B (10.2.2) and 1.0 cm3of Stock Solution C (10.2.3).10.3.2 Label another bottle, E, and add 0.4 c
36、m3of StockSolution B (10.2.2) and 1.0 cm3of Stock Solution C (10.2.3).10.3.3 Label another bottle, F, and add 0.6 cm3of StockSolution B (10.2.2) and 1.0 cm3of Stock Solution C (10.2.3).10.3.4 Label the last bottle, G, and add 1.5 cm3of StockSolution B (10.2.2) and 1.0 cm3of Stock Solution C (10.2.3)
37、.NOTE 4These calibration mixtures provide concentrations of styrenesimilar to the expected content in the latex and provide good dispersion ofthe styrene and vinyl toluene in the water phase. They also provideinternal standard concentrations in the same general range as styrene andcan be used to che
38、ck response factors and detector linearity. Thecalibration standards correspond to the following styrene and vinyltoluene levels when mixed with5goflatex:Calibrationmixture Styrene, mg/kg Vinyl toluene, mg/kgD 100 600E 400 600F 600 600G 1500 60010.4 Response FactorsInject 1 mm3(1 L) of each cali-bra
39、tion mixture D through G into the gas chromatograph anddetermine the response factor for styrene and vinyl toluene.See the Annex for examples of response factor calculations.11. Procedure11.1 Dry an aliquot of the sample latex to constant mass at|La105C. Calculate the total solids according to 12.3.
40、 (Thetotal solids content of the latex must be known if the residualstyrene on a dry rubber basis is required.)11.2 Accurately weigh approximately5goflatex to60.1 mg into a sample vial (6.5); then add 5.0 cm3of StockSolution A (10.2.1) and 1.0 cm3of Stock Solution C (10.2.3).NOTE 5It has been observ
41、ed that adjusting the internal standardcontent to give a peak height of approximately the peak height of thestyrene in the sample, improves quantitative recovery.11.3 Agitate the vial for 5 min, either manually or mechani-cally.11.4 Inject 1 mm3(1 L) of this solution into the gaschromatograph and ob
42、tain the area of the styrene and vinyltoluene peaks. If injection is difficult, dilute with additionalStock Solution A (10.2.1) or water (7.1).11.5 Check for matrix effects periodically according to11.5.1 and 11.5.2. (Adverse matrix effects have not beenobserved in most latex systems.)11.5.1 Repeat
43、11.2 for test portion preparation; then add 0.4cm3of Stock Solution B and an additional 1.0 cm3of StockSolution C. Continue as in 11.3 and 11.4. This preparation willcontain added styrene at 400 mg/kg (ppm) and additional vinyltoluene at 600 mg/kg (ppm). If the analyst so desires, addi-tional vinyl
44、toluene need not be added, provided the styreneand vinyl toluene ratios will remain within the calibrationrange.11.5.2 Calculate according to 12.1 for residual styrene. Ifthe results indicate that the matrix does affect these results (anincrease of residual styrene by three times the standarddeviati
45、on over that found in 11.2 through 11.4), the latex mustbe analyzed with this addition technique. See the Annex forsample calculation.12. Calculations12.1 Calculate the residual styrene on an as-received, wet,basis as follows:Residual styrene, mg/kg ppm! 5 A 3B 3C 31000/M 3D! (1)where:A = milligrams
46、 of vinyl toluene added as internal standard,B = response factor for styrene,C = area of the styrene peak,M = mass of the latex in grams, andD = area of the vinyl toluene peak.12.2 Calculate the residual styrene on the dry rubber asfollows:Residual styrene, mg/kg ppm! 5 A 3B 3C 31000/M 3T! 3D!(2)whe
47、re:A = milligrams of vinyl toluene added as internal standard,B = response factor for styrene,C = area of the styrene peak,M = mass of the latex in grams,D = area of the vinyl toluene peak, andT = decimal equivalent of the percent total solids.12.3 Calculate the total solids (T) of the sample as fol
48、lows:Total solids, % 5Md3100/Mw!(3)D4026 06 (2017)3where:Md= mass of the dried sample in grams, andMw= mass of the wet latex in grams.13. Report13.1 The report shall contain the following information:13.1.1 Full identification of the sample and date of analysis,13.1.2 Average residual styrene from t
49、wo determinations,that fall within the precision found in Section 14,13.1.3 Whether the residual styrene has been calculated ona wet or dry basis, and13.1.4 Total solids content of the latex.14. Precision and Bias414.1 This precision and bias section has been prepared inaccordance with Practice D4483. Refer to Practice D4483 forterminology and other statistical calculation details.14.2 A Type 1 (interlaboratory) precision was evaluated.Both repeatability and reproducibility are short term, a periodof a few days separates replicate tes
