1、Designation: D6133 02 (Reapproved 2014)Standard Test Method forAcetone, p-Chlorobenzotrifluoride, Methyl Acetate or t-ButylAcetate Content of Solventborne and Waterborne Paints,Coatings, Resins, and Raw Materials by Direct Injection Intoa Gas Chromatograph1This standard is issued under the fixed des
2、ignation D6133; 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
3、 or reapproval.1. Scope1.1 This test method is for the determination of the total-concentration of acetone, p-chlorobenzotrifluoride, methylacetate, or t-butyl acetate, or combination of any of the four, insolvent-reducible and water-reducible paints, coatings, resins,and raw materials. Because unkn
4、own compounds that co-elutewith the analyte being measured or with the internal standard,will lead to erroneous results, this test method should only beused for materials of known composition so that the possibilityof interferences can be eliminated. The established workingrange of this test method
5、is from 1 % to 100 % for each analyteby weight.1.2 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.1.3 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility
6、 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.2. Referenced Documents2.1 ASTM Standards:2D3271 Practice for Direct Injection of Solvent-ReduciblePaints Into a Gas Chromatograph for Solvent A
7、nalysisD3272 Practice for Vacuum Distillation of Solvents FromSolvent-Reducible Paints For Analysis (Withdrawn2008)3D6438 Test Method for Acetone, Methyl Acetate, andParachlorobenzotrifluoride Content of Paints, and Coat-ings by Solid Phase Microextraction-Gas Chromatogra-phyE177 Practice for Use of
8、 the Terms Precision and Bias inASTM Test MethodsE691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test Method3. Summary of Test Method3.1 A suitable aliquot of whole paint is internallystandardized, diluted with an appropriate solvent, and theninjected into a gas
9、chromatographic column that separates thechosen analytes from other volatile components. The analytecontent is determined from area calculations of the materialsproducing peaks on the chromatogram.4. Significance and Use4.1 With the need to calculate volatile organic content(VOC) of paints, and with
10、 acetone, p-chlorobenzotrifluoride,methyl acetate and t-butyl acetate4considered as exemptvolatile compounds, it is necessary to know the content ofthese analytes. This gas chromatographic test method providesa relatively simple and direct way to determine their content.However, because the detector
11、s used in this test method are notselective, and because some coatings are very complexmixtures, compounds may be present in the sample that coelutewith the analyte, giving a result that is erroneously high. Or acomponent may elute with the internal standard, giving a resultthat is erroneously low.
12、It is therefore important to know thecomposition of the sample to ensure that there are nointerferences, under the analysis conditions used. Test MethodD6438 employs mass-spectral detection of analytes and may beused as an alternative method.1This test method is under the jurisdiction of ASTM Commit
13、tee D01 on Paintand Related Coatings, Materials, and Applications and is the direct responsibility ofSubcommittee D01.21 on Chemical Analysis of Paints and Paint Materials.Current edition approved July 1, 2014. Published August 2014. Originallyapproved in 1997. Last previous edition approved in 2008
14、 as D6133 02 (2008).DOI: 10.1520/D6133-02R14.2For 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.3The last approv
15、ed version of this historical standard is referenced onwww.astm.org.4At the time of the revision of this test method, t-butyl acetate was not yetapproved as an exempt solvent, but was under review by the USEPA and wasexpected to be approved. Therefore, it has been included in this test method.Copyri
16、ght ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States15. Apparatus5.1 Gas ChromatographAny instrument with temperatureprogramming capability may be used. It should be equippedwith a flame ionization detector (see Table 1).5.2 ColumnAny column tha
17、t provides baseline separationof the analyte of interest (acetone, p-chlorobenzotrifluoride,methyl acetate or t-butyl acetate), the internal standard, and anyvolatile present in the samples may be used. It should beunderstood that column performance may be influenced bymanufacturing conditions, such
18、 as type of deactivation andchemical bonding/crosslinking used. One or more of thefollowing column types may be used. In terms of durability andover all efficiency, a bonded phase poly (5 % phenyl 95 %dimethylsiloxane) type of column should be considered first.(Any reference to specific product bran
19、ds does not indicate anendorsement for that particular brand of column).5.2.1 Capillary, 25 to 60 m, 0.25 mm-inside diameter, 0.25to 1.0-m film thickness, fused silica bonded phase poly (5 %phenyl 95 % dimethylsiloxane (DB-5, HP-5, Rtx-5, Ultra-2,BP-5, CP-Sil 8 CB, etc.).5.2.2 Capillary, 25 to 60 m,
20、 0.25-mm inside diameter, 0.25to 1.0-m film thickness, fused silica FFAP (polyethyleneglycol nitrophthalic acid ester phase).5.2.3 Capillary, 25 to 60 m, 0.25-mm inside diameter, 0.25to 1.4-m film thickness, fused silica bonded phase poly (6 %cyanopropyl/phenyl, 94 % dimethylsiloxane) (DB-624, SPB-6
21、24, Rtx-624, etc.).5.3 RecorderA recording potentiometer with a full-scaledeflection of 1 to 10 mV, full-scale response time of2sorlessand sufficient sensitivity and stability to meet the requirementsof 5.1. The use of a reporting electronic integrator or computerbased data system is preferred.6. Co
22、lumn Peak Interferences6.1 The following compounds are known to co-elute orotherwise interfere with the analysis on a DB-5 type column:(a) Acetoneisopropanol, propylene oxide, acetonitrile, and(b) Cyclohexanolsec-amyl acetate.6.2 The following compound is known to co-elute orotherwise interfere with
23、 the analysis on an FFAP type column:(a) Cyclohexanolbutyl cellosolve.6.3 The analyst must verify that, under the analysis condi-tions being used, none of the components of the sampleinterfere with the analyte being quantitated or with the internalstandard being used.7. Reagents and Materials7.1 Pur
24、ity of ReagentsUse reagent grade chemicals in alltests, unless otherwise specified. Other grades may be used,provided it is first ascertained that the reagent is sufficientlyhigh purity to permit its use without lessening the accuracy ofthe determination.7.2 Tetrahydrofuran (THF)high performance liq
25、uid chro-matography (HPLC) grade, uninhibited.7.3 Cyclohexanol98+ %.7.4 AcetoneHPLC grade.7.5 p-Chlorobenzotrifluoride98+ %.7.6 Methyl Acetate99+ %.7.7 t-Butyl Acetate99+ %.7.8 Waternanopure.7.9 Chromatography Gases: Helium of 99.9995 % purity orhigher.Hydrogen of 99.9995 % minimum purity (see Note
26、1).Air, “dry” quality, free of hydrocarbons.NOTE 1The preferred choice of carrier gas is hydrogen, but helium ornitrogen may also be used. Chromatographic analysis time will increaseand there may be a possible reduction in resolution.7.10 Liquid Charging Devicesmicro syringes of 10 or 25L capacity.7
27、.11 Analytical Balancefour places (0.0001 g).7.12 Sealable Vials7-mL screw cap.7.13 Medicine Droppers.7.14 Autosampler Vials.7.15 Pipete5-mL glass or autopipete.8. Hazards8.1 Check the suppliers Material Safety Data Sheet(MSDS) on all chemicals before use.9. Preparation of Apparatus9.1 Install the c
28、olumn in the chromatograph following themanufacturers directions and establish the operating condi-tions required to give the desired separation (see Table 1).Allow sufficient time for the instrument to reach equilibrium asindicated by a stable base line.TABLE 1 Suggested Instrument ConditionsDetect
29、or Flame Ionization Detection (FID)Hydrogen Flow 30 mL/minAir Flow 400 mL/minMake-up (Helium) 30 mL/minCarrier Gas (Hydrogen) 40 cm/sDetector Temperature 250CInjection Port Temperature 200CASplit Ratio 50:1BInitial Oven Temperature 40CInitial Temperature Hold Time 5 minProgram Rate 1 4C/minProgram T
30、ime 1 5 minFinal Temperature 1 60CProgram Rate 2 20C/minProgram Time 2 8 minFinal Temperature 2 220CFinal Temperature Hold Time 2 minTotal Run Time 20 minInjection Volume 1.0 LAThe injection port temperature can be decreased to permit the analysis ofthermally unstable samples; however, each case mus
31、t be individually investigated.BThe split ratio may be adjusted according to the theoretical level of solventcomposition.D6133 02 (2014)210. Calibration10.1 Using the information in Table 1 (as a guide), select theconditions of temperature and carrier gas flow that give thenecessary resolution of th
32、e desired analytes from interferencesin the samples.10.2 Determination of Relative Response FactorsCyclohexanol, or another suitable compound, is used as aninternal standard. The internal standard used should be acompound that is not in the sample matrix, and does notco-elute with any other componen
33、t of the sample. Mostanalyses can be done utilizing cyclohexanol for the internalstandard providing it is soluble in the diluent solvent. Theresponse factor for each analyte relative to the standard isdetermined by means of the following procedure. It is goodpractice to determine the relative retent
34、ion time daily or witheach series of determinations.10.2.1 Prepare a standard with the desired analytes and theinternal standard. This is done in the following manner: A7-mL sealable vial is tared on an analytical balance. Eachdesired analyte and the internal standard are added at the 1 drop(;0.02 g
35、) level and their weights recorded. All weights shouldbe recorded to 0.1 mg. Deliver 5 mL of dilution solvent (THF)to this vial (see Note 2). Lower concentrations may beachieved through further dilution with THF if necessary.NOTE 2The solvent should always be injected separately for obser-vation of
36、contaminants and possible interference peaks, especially in traceanalysis. The suggested solvents do not preclude the selection of any othersolvent for dilution at the analysts discretion.10.2.2 Inject a 1.0 L aliquot of the standard mixture intothe injection port of the gas chromatograph. At the en
37、d of thechromatographic run, calibrate the integrator by following themanufacturers procedure for internal standard weight percentcalibration. If this capability is not available, refer to thefollowing calculations. See Figs. 1-3 for typical chromato-grams using the three listed columns.10.2.3 The r
38、esponse factor of each analyte is calculated asfollows:Ranalyte5Wi3 AanalyteWanalyte3 Ai(1)where:Ranalyte= response factor for the analyte being calibrated,Wi= weight of internal standard,Wanalyte= weight of the analyte being calibrated,Aanalyte= peak area for the analyte being calibrated, andAi= pe
39、ak area for the internal standard.11. Procedure11.1 Samples are prepared with respect to the amount of theselected analytes in the sample, or the viscosity, or both. Adiluting solvent must be chosen that satisfactorily dissolves thesample and at the same time does not interfere with or obscurethe an
40、alyte peaks in the sample. Most samples are easilydissolved in THF, while a 50/50 blend of nanopure water andTHF will disperse most latex samples.11.2 The prepared sample must be easily dispensed into thesyringe. For this reason, some samples may need to be dilutedfurther. Best results are obtained
41、when the analyte concentra-tion is reduced to about 1 % in the prepared sample. This isaccomplished by diluting the sample (1 g) with1gofdilutingsolvent for every percent of analyte present in the originalsample.11.3 Inject a 1.0 L aliquot of the prepared sample into thechromatographic column. The r
42、eporting integrator will displaythe peak retention times and areas of the analytes and internalstandard. The integrator will report the results directly inweight percentages based on the total sample. If a reportingintegrator is not available, manual calculations can be done.FIG. 1 GC Trace of Solve
43、nt Mix in Tetrahydrofuran (THF) on a 30 m, 0.25 mm ID Column With 5 % Phenyl/95 % Dimethylsiloxane PhaseD6133 02 (2014)311.4 If the sample contains solvent or monomer peakinterferences (for example on a DB-5 column, isopropanol hasthe same retention time as acetone), a second capillary columnwith a
44、different phase (FFAP for example) must be used toachieve adequate separation. If available, mass spectral confir-mation may also be used in place of analysis on a secondcolumn, if the mass spectra are sufficiently different to allowisolation of the compounds of interest.11.5 For difficult or pigmen
45、ted samples, the samples may becleaned up by vacuum distillation (see Practice D3272), orcentrifugation.11.6 Samples may also be screened for acetone,p-chlorobenzotrifluoride, methyl acetate, or t-butyl acetatecontent using Practice D3271.12. Calculation12.1 Calculate the weight percent of any of th
46、e analytes inthe sample from data obtained from the sample run (see 11.3)as follows:Analyte,%5Aanalyte3 Wi3100Ai3 Ws3 Ranalyte(2)FIG. 2 GC Trace of Solvent Mix in Tetrahydrofuran (THF) on a 30 m, 0.25 mm ID Column With FFAP PhaseFIG. 3 GC Trace of Solvent Mix in Tetrahydrofuran (THF) on a 60 m, 0.25
47、 mm ID Column With 624 PhaseD6133 02 (2014)4where:Aanalyte= area of the analyte peak,Ai= area of the internal standard peak,Wi= weight of internal standard added to the sample,Ws= weight of sample, andRanalyte= response factor for the analyte (determined in10.2.3).13. Precision and Bias13.1 Precisio
48、nThe precision estimates forp-chlorobenzotrifluoride, t-butyl acetate, methyl acetate, andacetone are based on an interlaboratory study in which 7different laboratories analyzed three times, 4 samples ofvarious solventborne materials containing from 22 to 57 %p-chlorobenzotrifluoride, 8 to 33 % t-bu
49、tyl acetate, 3 to 35 %methyl acetate, and 3 to 22 % acetone. The results obtainedwere analyzed statistically in accordance with Practice E691.Precision statistics were calculated for the total mass percent ofeach analyte in the 4 coatings and are presented in Table 2. Theterms repeatability limit and reproducibility limit are used asspecified in Practice E177.13.1.1 The average 95 % Repeatability Limit (within labo-ratory) coefficient or variation (relative) for each analyte,which represents the 95 % confidence limit for the differencebet
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