ASTM_D_4026_-_06_2012.pdf

Designation:D402606(Reapproved 2012)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 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 the re-sidual styrene content of styrene butadiene(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 ofapproximately 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 this 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.)2.Referenced Documents2.1 ASTM Standards:2D4483 Practice for Evaluating Precision for Test 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 mixed 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 styrene)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 separation 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 columns 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 300C range and injection ports must be operatedin the 200 to 210C range.NOTE1It 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 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 spuriouspeaks begin to appear and usually after about 20 injections.Ifglass liners are not available,metal liners,packed with glasswool,may be used.6.2 GasChromatographicColumns,Packings,andProgramsAny column,packing,or program listed in Table 1is satisfactory,as long as it produces narrow,well-resolved1This test method is under the jurisdiction of ASTM Committee D11 on Rubberand is the direct responsibility of Subcommittee D11.11 on Chemical Analysis.Current edition approved May 1,2012.Published May 2012.Originallyapproved in 1981.Last previous edition approved in 2006 as D4026 06.DOI:10.1520/D4026-06R12.2For 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.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 styrene 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).NOTE2Syringes may be cleaned by drawing water into 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,necessary for carryingout this procedure.6.8 Mechanical Shaker