ASTM D7823-2013 4375 Standard Test Method for Determination of Low Level Regulated Phthalates in Poly (Vinyl Chloride) Plastics by Thermal DesorptionGas Chromatography Mass Chromat.pdf

1、Designation: D7823 13Standard Test Method forDetermination of Low Level, Regulated Phthalates in Poly(Vinyl Chloride) Plastics by Thermal DesorptionGasChromatography/Mass Chromatography1This standard is issued under the fixed designation D7823; the number immediately following the designation indica

2、tes 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 provides a procedure to ide

3、ntify andquantify six phthalates by thermal desorption (TD) gas chro-matography (GC) mass spectrometry (MS). The phthalates areBBP, DBP, DEHP, DNOP, DINP and DIDP.NOTE 1The method can be extended to include other phthalates.1.2 Within the context of this method, “low level” is definedas 1000 ppm.1.3

4、 The values in SI units are to be regarded as standard.1.4 This test method includes references, notes and foot-notes that provide explanatory material. These notes andfootnotes (excluding those in the tables and figures) shall notbe considered as requirements of this method.1.5 This standard does n

5、ot 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.NOTE 2There is no known ISO equivalent

6、to this test method.2. Referenced Documents2.1 ASTM Standards:2D883 Terminology Relating to PlasticsD1600 Terminology forAbbreviated Terms Relating to Plas-ticsD3465 Test Method for Purity of Monomeric Plasticizers byGas ChromatographyD7083 Practice for Determination of Monomeric Plasticiz-ers in Po

7、ly (Vinyl Chloride) (PVC) by Gas Chromatogra-phyE355 Practice for Gas Chromatography Terms and Relation-shipsE594 Practice for Testing Flame Ionization Detectors Usedin Gas or Supercritical Fluid ChromatographyIEEE/ASTM SI10 Practice for Use of the InternationalSystem of Units (SI), the Modernized M

8、etric System3. Terminology3.1 DefinitionsFor definition of plastic terms used in thistest method, see Terminologies D883 and D1600.3.2 For units, symbols, and abbreviations used in this testmethod refer to Practices E594, E355,orSI10.3.3 Compounds and Instrumentation:3.3.1 (DOA) Hexanedioic acid, 1,

9、6bis(2ethylhexyl) esterCAS #1032313.3.2 (DINCH) 1,2Cyclohexanedicarboxylic acid, dinonylester, branched and linear CAS #4749195903.3.3 (DBP) 1,2Benzenedicarboxylicacid, 1,2dinbutylester CAS #847423.3.4 (BBP) Benzyl butyl phthalate CAS #856873.3.5 (DEHP) Bis(2Ethyhexyl) Phthalate CAS #1178173.3.6 (DN

10、OP) Di(nDioctyl) phthalate CAS #1178403.3.7 (DINP) 1,2Benzenedicarboxylicacid,diC810branched alkyl esters, C9rich (Jayflex) CAS#685154803.3.8 (DINP) 1,2Benzenedicarboxylicacid, 1,2diisononyl(Palatinol) CAS #285531203.3.9 (DIDP) 1,2Benzenedicarboxylicacid,diC911branched alkyl esters, C10rich (Jayflex

11、) CAS#685154913.3.10 (DIDP) 1,2Benzenedicarboxylicacid, 1,2diisodecylCAS #267614003.3.11 TD Thermal Desorption3.3.12 GC Gas Chromatography3.3.13 GC/MS Gas Chromatography/Mass Spectrometry3.3.14 PVC Poly (Vinyl Chloride)3.3.15 THF GC grade or higher “Tetrahydrofuran”3.3.16 DCM GC grade or higher “Met

12、hylene Chloride”3.3.17 EGAMS Evolved Gas Analysismass spectrometry3.3.18 FTIR Fourier Transform Infrared Spectroscopy1This test method is under the jurisdiction of ASTM Committee D20 on Plasticsand is the direct responsibility of Subcommittee D20.70 on Analytical Methods.Current edition approved Apr

13、il 1, 2013. Published April 2013. DOI: 10.1520/D7823-13.2For 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.Copyr

14、ight ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States13.3.19 TIC Total ion chromatogram3.3.20 DQO Data quality objectivesNOTE 3DINP and DIDP, when used in various PVC formulations aretechnical mixtures. Take care, when preparing the phthalate ca

15、librationstandard to use the technical grade. Here is specific information on DINPand DIDP. For more information, please refer to Appendix X3.Jayflex DIDP: 1,2Benzenedicarboxylicacid, diC911branched alkylesters, C10rich: CAS# 68515491.Jayflex DINP: 1,2Benzenedicarboxylicacid, diC810branched alkylest

16、ers, C9rich: CAS# 68515 480.4. Summary of Test Method4.1 200 mg of the PVC sample are dissolved in 10 mL ofTHF. 10 Lof the THF solution are analyzed using TDGC/MS.Phthalates are identified by their retention times and their massspectra. Quantification is based on the area of a designatedquant ion (S

17、IM or full scan)see Table 1. Standard addition isthe calibration method.NOTE 4Standard addition calibration will negate matrix interference.It also takes into account the overall performance of the instrumentationat the time the samples are analyzed.5. Significance and Use5.1 Identification and quan

18、tification of phthalates: DBP,BBP, DEHP, DNOP, DINP, and DIDP are required for regu-lated articles. Regulations include: EUDirective 2005/84/EC, USConsumer Product Safety Improvement Act of2008section 108, JapanHealth, Labor and Welfare Minis-try guideline No.336 (2010). This test method provides ap

19、rocedure to identify and quantify regulated phthalates in PVC.5.2 Other techniques successfully used to separate andidentify phthalates in PVC include GC/MS, HPLC/UV, HPLC/MS, FTIR, and GC/FID (flame ionization detector).6. Interferences6.1 Retention times for GC are dependent on several vari-ables

20、and it is possible to have two or more components withidentical retention times. The analyst shall take the necessarysteps to insure that adequate separation of the plasticizercomponents is achieved and or the ions used to monitor for atarget phthalate are free of interference. This includes, but is

21、not limited to changing the selectivity of the chromatographiccolumn. Calibration by standard addition offers the advantageof minimizing interferences.6.2 When using a TDGC/MS method, care must be taken toensure that the sample cups are inert and clean. Any and allsolvents used to prepare standards

22、and sample solutions mustbe free of contamination.6.3 The presence or absence of each phthalate is based uponthree criteria: (1) the relative retention time of the peak (2) thepresence or absence of the quant ion and the two confirmingions and (3) the ratio of the quant and the confirming ion onemus

23、t satisfy the established guideline (see Table 1).6.4 Calculating the phthalate concentrations using the areasof compound specific ions and standard addition significantlyreduces interference from nontarget compounds.7. Apparatus7.1 Gas chromatograph/mass spectrometer capable of oper-ating in the 75

24、 to 350C range.NOTE 5Optional but recommended: Ventfree GC/MS Adapter. Thisfacilitates the rapid conversion between detailed analysis and evolved gasanalysis.7.2 Thermal desorption unit capable of heating the samplefrom 100 to 350C at 20C/min.7.3 Inert, reusable or disposable sample containers or cu

25、ps.7.4 GC capillary column: UA5 (5 % diphenyl95 % poly(dimethylsiloxane) stainless steel, 30 m by 0.25 mm ID with a0.25 m film thickness, or equivalent.7.5 Integrator or data handling system, capable of measur-ing peak areas and retention times to four significant figures.7.6 Analytical balance, cap

26、able of weighing to 60.000001 g(1 g). If using a balance capable of weighing to 60.00001 g(10 g), weight used in the sample and standard preparationmust be scaled accordingly in order to ensure that the data isaccurate to three significant figures.7.7 Pressure regulators, for all required gas cylind

27、ers.7.8 Flow meter, or other means of measuring gas flow rates60.1 mL/min.8. Reagents and Materials8.1 Helium carrier gas, chromatographic grade.8.2 Methylene chloride (DCM) or nhexane for preparingthe phthalate standard solution (Solution #1, 10.2), spectralquality or chromatographic grade.8.3 Tetr

28、ahydrofuran (THF), or a solvent suitable for prepar-ing the PVC sample (Solution #2, 10.3), spectral quality orchromatographic grade.8.4 Standards of the appropriate phthalates for use whenconstructing an external calibration curve or preparing Solution#3 (10.4) used for standard addition. See Note

29、2.9. Safety and Precautions9.1 Use THF and methylene chloride in a wellventilatedspace.TABLE 1 Ions and Ion Ratios Used to Identify Each PhthalateDBP BBP DEHP DNOP DINP DIDPQuant ion 223 206 279 279 293 307Confirmion 1149 149 149 149 149 149Area ratio(10%)(Quant/Confirm1)0.04 0.23 0.08 0.06 0.20 0.1

30、2Confirmion 2167 167 167 167 167 167D7823 13210. Preparation of the Analytical Samples(based upon usinga1gbalance)Weights must be scaled up if using a 10-g balance.10.1 Three solutions must be prepared: (1) a stock solutionof the target phthalate standards, (2) a solution of the sampleand (3) the sa

31、mple solution spiked with the standard stocksolution.10.2 Solution #1Prepare a stock standard solution of thephthalates by dissolving 0.30 mg of each phthalate in 10 mL ofmethylene chloride (0.30 mg/10 mL). Nhexane has also beenused with success. See Fig. 1 for a typical chromatogram.10.3 Solution #

32、2Dissolve 200 mg of the sample in 10 mLTHF (200 mg/10 mL). Shake (or sonicate) the solution for fiveminutessee Note 6. The solution may range from clear toslightly cloudy. Place 10 L of the sample solution in a cleansample cup. Evaporate the solvent; the sample is ready toanalyze. See Figs. 2 and 3

33、for example chromatograms.NOTE 6A critical step in the accurate determination of phthalates issample homogeneity. This is discussed in more detail in Appendix X2.NOTE 7The THF sample solution may contain inorganic material.Studies have shown that the presence of insoluble inorganic material willnot

34、affect either the accuracy or precision of the phthalate determination.10.4 Solution #3Place 10 L of the sample solution (#2)into a clean sample cup. Add 10 L of the phthalate standardsolution (#1). Evaporate the solvent.NOTE 8To expedite the evaporation process, pass a steady stream ofa high purity

35、 inert gas using clean, (plasticizer- and additive-free) tubingover the sample cup.11. Procedure11.1 Establish that the analytical system is free of phthalatecontamination by analyzing 10 Lof THF.Acceptable levels ofbackground contamination will be determined by the projectspecific Data Quality Obje

36、ctives.FIG. 1 Solution #1Phthalates Standard Mixture (see 10.2)D7823 133FIG. 2 Solution #2Chromatograms (TIC) of PVC with Three Different Plasticizers, TD-GC/MS Analysis (see 10.3 and 11.3)D7823 134FIG. 3 Solution #2Reproducibility of PVC-DINCH (n=6) (see 10.3 and 11.3)D7823 13511.2 Establish the re

37、lative retention time and mass spectrumof each phthalate using Solution #110.2: The followingconditions were used to obtain the example chromatogramsshown in Figs. 1-4:Thermal Desorption (TD)GC/MS AnalysisTD temperature: 100 20C/min 320C (5 min hold)Py interface: 320C (Auto mode),GC injector : 300CF

38、IG. 4 Solution #3Standard Addition (see 11.7)D7823 136GC oven: 80 (1 min hold) to 200C (at 50C/min) to 320C (15C/min, 2 min hold)Solvent delay: 6 minColumn: UA5 (5 % Diphenyl95 % dimethylpolysiloxane) 30 m by 0.25 mm i.d,0.25 m film) or equivalentColumn He flow: 1.2 mL/min, Split ratio: 1/20Mass ran

39、ge: 29600 m/z,Scan speed: 2.57 scans/sec,Threshold: 50MSD Transfer Line Temp.: 300CIon Source (EI) temp.: 230CNOTE 9Confirm the TD zone using Evolved GasAnalysis (EGA)MS.The total ion chromatogram of the sample (Solution #2, 10.3) needs to besimilar to that presented in Appendix X1.NOTE 10The use of

40、 alternative GC columns or chromatographicconditions normally results in adequate separation of the phthalates. Thosetechniques are allowed as long as the same or a similar separation isachieved.11.3 Analyze the sample (Solution #2, 10.3) using theconditions outlined in 11.2. Typical chromatograms a

41、re shownin Figs. 2 and 3. The precision of the TD method is shown inFig. 3.11.4 Peak identifications are based on relative retentiondata, full scan extracted ion chromatograms of both the quantand confirming ions and the ion area ratios as indicated inTable 1. Phthalate quantification is based upon

42、the peak areasof the quant ions listed in Table 1. The assumption being madeis that the sole source of the quant ion at a predeterminedretention time is the phthalate and therefore the peak area of thequant ion can be used to accurately determine the amount ofthe phthalate.11.5 If using selected ion

43、 monitoring (SIM), peak identifi-cation is based solely on the presence or absence of the quantion and the two confirming ions at a predetermined retentiontime. Quantification is based on the area of the quant ion.11.6 When DINP and DIDP are copresent in a sample orstandard, m/z 127 should be used a

44、s a qualifying ion for DINPand m/z 289 for DIDP. This is because DINP and DIDP partialcoelute and both produce m/z 149 and 167. If 149 qualifier ionratios are set when DINPand DIDPare at equal concentrations,then any samples with different ratios will produce substan-tially different 149/167 ratios,

45、 potentially leading to a falsenegative.NOTE 11A typical total ion chromatogram obtained using the condi-tions specified in 11.2 is shown in Fig. 1. Because the absolute retentiontimes are dependent upon the entirety of the GC system; relative retentiontimes can be used to identify each phthalate. T

46、he choice of the basephthalate is left to the laboratory.11.7 Quantification is done using standard addition.AnalyzeSolution #3. A typical total ion chromatogram is shown in Fig.4.Analytical precision is presented in the table at the bottom ofFig. 4. Standard addition is very useful when it is diffi

47、cult toeliminate interferences from the sample matrix. This is oftenthe case when analyzing PVC where DINCH, Mesamoll orboth are present.11.8 Attention should be paid to the chromatographic peakshape of the DNOP as partial coelution with dioctylterephthalate (which produces all the same ions in diff

48、er-ent ratios) has been observed. Careful integration of quantify-ing ion (m/z 279) response that is only due to DNOP and notDOTP should take into account principals of chromatographicpeak shape and areas.”3NOTE 12The quality of the calibration is monitored using thecoefficient of determination R2.

49、Typically the R2values of all targetphthalates are 0.99 or bettersee Fig. 5.12. Example calculations12.1 A typical set of standard addition curves are presentedin Fig. 5. Included in Fig. 5 is an example of how to calculatethe concentration of the target phthalate and the analyticalprecision (n=6) of the method.13. Quality Control13.1 Perform the quality checks outlined in Table 2 on aroutine basis.TABLE 2 System Performance VerificationSample