1、Designation: D 6886 03 (Reapproved 2009)Standard Test Method forSpeciation of the Volatile Organic Compounds (VOCs) inLow VOC Content Waterborne Air-Dry Coatings by GasChromatograpy1This standard is issued under the fixed designation D 6886; the number immediately following the designation indicates
2、 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 is for the determination of th
3、e weightpercent of individual volatile organic compounds in low VOCcontent waterborne latex air-dry coatings. The method isintended primarily for analysis of waterborne coatings in whichthe material VOC content is below 5 weight percent. Themethod has been used successfully with higher VOC contentwa
4、terborne coatings.1.2 This method may also be used to measure the exemptvolatile organic compound content (acetone, methyl acetate,and p-chlorobezotrifluoride) of waterborne coatings. The meth-odology is virtually identical to that used in Test MethodD 6133 and similar to that used in Test Method D
5、6438.1.3 Volatile compounds that are present at the 0.05 weightpercent level or greater can be determined. Solid phasemicroextraction will detect volatile compounds at lower levels.1.4 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstan
6、dard.1.5 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.2. Referen
7、ced Documents2.1 ASTM Standards:2D 1475 Test Method For Density of Liquid Coatings, Inks,and Related ProductsD 2369 Test Method for Volatile Content of CoatingsD 3792 Test Method for Water Content of Coatings byDirect Injection Into a Gas ChromatographD 3925 Practice for Sampling Liquid Paints and R
8、elatedPigmented CoatingsD 3960 Practice for Determining Volatile Organic Com-pound (VOC) Content of Paints and Related CoatingsD 4017 Test Method for Water in Paints and Paint Materialsby Karl Fischer MethodD 6133 Test Method for Acetone, p-Chlorobenzotrifluoride,MethylAcetate or t-ButylAcetate Cont
9、ent of Solventborneand Waterborne Paints, Coatings, Resins, and Raw Mate-rials by Direct Injection Into a Gas ChromatographD 6438 Test Method for Acetone, Methyl Acetate, andParachlorobenzotrifluoride Content of Paints, and Coat-ings by Solid Phase Microextraction-Gas ChromatographyE 177 Practice fo
10、r Use of the Terms Precision and Bias inASTM Test MethodsE 691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test Method3. Terminology3.1 Abbreviations:3.1.1 CW/DVBCarbowaxy/divinylbenzene3.1.2 DB2-(2-butoxyethoxy)ethanol; Butyl Carbitoly;diethylene glycol monobutyl
11、 ether3.1.3 EB2-butoxyethanol; Butyl Cellosolvey; ethyleneglycol monobutyl ether3.1.4 EGethylene glycol3.1.5 FIDflame ionization detector3.1.6 F-VOCformulation data calculated volatile organiccompound in g/(L-water)3.1.7 GCgas chromatograph3.1.8 PGpropylene glycol3.1.9 % RSDpercent relative standard
12、 deviation3.1.10 SPMEsolid phase microextraction3.1.11 Std Devstandard deviation3.1.12 TX2,2,4-trimethypentane-1,3-diol, monoisobu-tyrate; Texanoly3.1.13 VOCvolatile organic compound1This test method is under the jurisdiction of ASTM Committee D01 on Paintand Related Coatings, Materials, and Applica
13、tions and is the direct responsibility ofSubcommittee D01.21 on Chemical Analysis of Paints and Paint Materials.Current edition approved June 1, 2009. Published June 2009. Originallyapproved in 2003. Last previous edition approved in 2003 as D 6886 - 03.2Annual Book of ASTM Standards, Vol 06.01.For
14、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.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700,
15、 West Conshohocken, PA 19428-2959, United States.3.1.14 X-VOCexperimental volatile organic compound ing/(L-water)4. Summary of Test Method4.1 A known weight of coating is dispersed in tetrahydro-furan (THF), internally standardized, and analyzed by capillarygas chromatography to give a speciated com
16、position of thevolatile organic compounds and exempt organic compounds, ifany, present in the coating. Summation of the individualvolatile organic compound weight fractions gives the totalVOC content of the coating measured in weight percent (Note1).NOTE 1Using the provisions of Practice D 3960, the
17、 VOC content ofcoatings measured in g/L minus water, or other units, may be determined.Since the determination of weight percent VOC in the present method isby direct measurement, either the water fraction (Test Method D 3792 orTest Method D 4017) or the nonvolatile fraction (Test Method D 2369)may
18、be determined indirectly in the application of Practice D 3960. Theequations for calculating regulatory VOC content when no exempt volatilecompounds are present are:VOC 5fVOCDP!1 2 1 2 fNV2 fVOC!DP/DW!#(1)orVOC 5fVOCDP!1 2 fWDP/DW!#(2)where:DP,fNV,fVOC, and fW= coating density, nonvolatile fraction,
19、VOC fraction, and water fraction, respec-tively.4.2 Direct GC/FID, GC/MS and solid phase microextraction/ gas chromatography (SPME/GC) of the coating may be usedto facilitate identification of the volatile compounds present ina coating. Table X1.1 lists the GC retention times for thevolatile compoun
20、ds which may be found in low VOC contentwaterborne air-dry coatings. Table X1.1 also lists possibleinternal standards for use in the analysis and minor volatilecomponents which are sometimes found in waterborne coat-ings (Note 2).NOTE 2The analyst should consult MSDS and product data sheets forpossi
21、ble information regarding solvents which may be present in aparticular coating. SPME/GC may be used to ascertain that decompositionvolatiles are not measured.5. Significance and Use5.1 In using Practice D 3960 to measure the regulatory VOCcontent of coatings, precision tends to be poor for low VOCco
22、ntent waterborne coatings because the VOC weight fractionis determined indirectly. The present method first identifies andthen quantifies the weight fraction of individual VOCs directlyin low VOC content waterborne air-dry coatings. The totalVOC weight fraction can be obtained by adding the individu
23、alweight fraction values (Note 3).NOTE 3An effort is currently underway in California to considerchanging mass-based VOC regulations for architectural coatings toreactivity-based VOC regulations. In California, reactivity based regula-tions have already been implemented for aerosol coatings, that is
24、,MIR-indexed regulations (California Air Resources Board). Reactivitybased regulations would require knowing the weight fractions of eachindividual volatile compound present in a coating.5.2 SPME/GC makes it possible to identify very low levelsof volatile compounds in a coating and could serve to ma
25、ke itpossible to identify the presence of hazardous air pollutants(HAPs).6. Apparatus6.1 SPME Sampling Apparatus and Fibers,3manualSPME holders fitted with a 70 m Carbowaxy/Divinylbenzene(CW/DVB) StableFlex fiber assembly.6.2 Gas Chromatograph, FID Detection with ElectronicData Acquisition SystemAny
26、 capillary gas chromatographequipped with a flame ionization detector and temperatureprogramming capability may be used. Electronic flow control,which gives a constant carrier gas flow, is highly recom-mended.6.3 Standard FID Instrument Conditions:Detector Flame ionizationColumns Primary column: 30
27、m by 0.25 mm 5 % phenyl/95 % methylsiloxane (PMPS) (Note 4),1.0mfilmthickness.Confirmatory Columns: 30 m by 0.25 mm polydimethylsiloxane(PDMS), 0.25 m film thickness; 30 m by 0.25 mmCarbowaxY (CW), 0.25 m film thickness.Carrier Gas HeliumFlow Rate 1.0 mL per min, constant flow (24.9 cm/s at 40)Split
28、 Ratio VariableTemperatures, CInlet 260Detector 270Initial 40 for 4 minRate 10 per min to 250, hold 5 minNOTE 4The column designated as PMPS is commercially availablefrom several vendors by the following designations: DB-5, SPB-5, HP-5,AT-5, CP Sil 8CB, RTx-5, BP-5.7. Reagents and Materials7.1 Purit
29、y of ReagentsReagent grade chemicals shall beused in all tests. Unless otherwise indicated, all reagents shallconform to the available specifications of the Committee onAnalytical Reagents of the American Chemical Society. Othergrades may be used, provided it is first ascertained that thereagent is
30、of sufficiently high purity to permit its use withoutlessening the accuracy of the determination.7.2 Carrier Gas, helium of 99.995 % or higher purity.7.3 Tetrahydrofuran (THF), HPLC grade.7.4 1-Propanol, p-fluorotoluene, cyclohexanol,p-chlorotoluene and p-cymene, 99 + mole %.7.5 The volatile organic
31、 compounds listed in Table X1.1.7.6 Fluorocarbon-faced septum vials, 20 mL and 40 mLcapacity.8. Column and Fiber Conditioning8.1 The capillary columns should be conditioned accordingto the manufacturers recommendation. The columns may thenbe used indefinitely without further conditioning.8.2 The SPM
32、E fiber should be conditioned and used accord-ing to the manufacturers recommendation.3Available from the Supelco Company, Supelco Park, Bellefonte, PA 16823-0048.D 6886 03 (2009)28.3 The SPME fiber should be inserted into a 260Cinjection port for 30 s prior to each sampling event.9. Preparation of
33、Standards9.1 Prepare a stock mixture of ethylene glycol (EG), pro-pylene glycol (PG), ethylene glycol monobutyl ether (EB),p-cymene (CY) or other suitable internal standard, diethyleneglycol monobutyl ether (DB), and Texanol (TX) by weighingone or two grams of each into an appropriate vial. The weig
34、htof each component should be approximately the same anddetermined to 0.1 mg. Mix the contents.9.2 Transfer approximately 100 L of the stock mixture to aseptum-capped vial containing 10 mL of THF and mix thecontents (Note 5). This solution will contain each of the knownanalytes at a concentration of
35、 approximately 2 mg/mL.NOTE 5The solvents EG, PG, EB, DB and Texanol are widely used inthe manufacture of low VOC content waterborne air-dry coatings and maybe expected as highly probable components of these coatings. Thetetrahydrofuran solvent must be analyzed by GC to determine if possibleimpuriti
36、es interfere/coelute with the analytes being tested.9.3 Chromatograph the solution in 9.2 by injecting 1 L intothe PMPS column using the chromatographic conditions givenin 6.3. Calculate the relative response factors for each of theanalytes relative to the p-cymene internal standard using therelatio
37、nship:RF 5AA * MIAI * MA(3)where:RF = relative response factor,AA = area of analyte,MI = weight of internal standard (from 9.1),AI = area of internal standard, andMA = weight of analyte (from 9.1).10. Paint Analysis10.1 Using a 100 mL volumetric flask, make up a concen-trated standard solution conta
38、ining p-cymene (or other suitableinternal standard) in THF at a concentration of approximately1 g per 100 mL and known to the nearest 0.1 mg.10.2 Using standard quantitative dilution techniques, dilutethe concentrated standard solution to give a working standardsolution such that the internal standa
39、rd concentration is near 1mg per mL. Calculate the actual concentration.10.3 Pipette 10 mLof working standard solution into a 20 or40 mL vial and close with a fluorocarbon-faced septum cap.Using a disposable 1 mL syringe, add approximately 0.6 to 0.8g of the well-mixed paint through the septum cap a
40、nd weigh to0.1 mg (Note 6). Mix the contents vigorously by shaking for 1min followed by sonication for 5 min. Let the vial stand topermit pigments, if any, to settle.NOTE 6The paint should be drawn into the syringe without anattached syringe needle. Excess paint is wiped from the syringe and theneed
41、le is then attached for paint transfer. The mass of the paint may bedetermined by either the difference in the weight of the filled and emptysyringe or by the difference in the weight of the vial before and afteradding paint. When adding the paint to the THF in the vial, care should betaken that the
42、 paint falls directly into the THF solution containing theinternal standard.10.4 Chromatograph the solution in 10.3 by injecting 1 Linto the PMPS capillary column using the standard conditionsdescribed in 6.3. Adjust the split ratio to give well-definedchromatographic peaks. Identify the volatile co
43、mpoundspresent (Note 7) and calculate the weight fraction of each in thecoating using the relationship:%X 5AA!MI!100!AI!RF!MC!(4)where:X = one of several possible volatile compounds in thecoating,RF = relative response factor of compound X,AA = peak area of compound X,MI = weight of internal standar
44、d in 10 mL THF,AI = peak area of internal standard, andMC = weight of coating.NOTE 7If volatile compounds other than those in the standard (9.1)are present in the coating, the identity should be confirmed by retentiontime comparison with authentic material and the relative response factorshould be d
45、etermined as outlined in 9.1-9.3. Commercial Texanol maycontain small amounts of 2,2,4-trimethylpentane-1,3-diol which elutesapproximately 0.5 min before butyl carbitol. Acetone and isopropylalcohol have nearly the same retention time on a 5 % phenyl/95 % PDMScolumn and if either is found, their ide
46、ntities should be confirmed on adifferent column. Isobutyl alcohol coelutes with the solvent (THF) andmust be determined on a different column. SPME (11.2) is especiallyuseful for confirming the presence of isobutyl alcohol since no THF isused in this procedure.11. Solid Phase Microextraction Proced
47、ure11.1 Since a dispersion of coating in THF is injected into arelatively hot GC injection port, peaks representing decompo-sition products may be observed and should not be consideredas VOCs. Solid phase microextraction allows sampling of mostVOCs at low temperature and may be used to determine if
48、GCpeaks observed in the direct GC analysis (Section 10) areactual VOCs or decomposition products. If desired, the SPMEprocedure may be used prior to direct analysis to determinewhich VOCs are present in the coating. If GC/MS is available,the SPME procedure is especially useful for identification ofV
49、OCs and exempt compounds present in a coating sample.11.2 Place approximately 5 to 10 g of liquid waterbornecoating into a 40 mL fluorocarbon-faced septum vial. If usinga smaller vial, reduce the coating amount. Close the vial witha fluorocarbon-faced septum cap and heat to 55 to 60C in anoven or other suitable heat source (oil bath, water bath, heatedmetal block). Do not let the contents contact the inside face ofthe septum cap. Insert the SPME fiber through the septum capand sample the headspace for 3 to 4 min using a condition
