1、Designation: D6886 141Standard Test Method forDetermination of the Weight Percent Individual VolatileOrganic Compounds in Waterborne Air-Dry Coatings by GasChromatography1This standard is issued under the fixed designation D6886; the number immediately following the designation indicates the year of
2、original 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.1NOTEResearch report was added editorially in August 2014.1. Scope1.1 T
3、his test method is for the determination of the weightpercent of individual volatile organic compounds in water-borne air-dry coatings (Note 1).1.2 This method may be used for the analysis of coatingscontaining silanes, siloxanes, and silane-siloxane blends.1.3 This method is not suitable for the an
4、alysis of coatingsthat cure by chemical reaction (this includes two-componentcoatings and coatings which cure when heated) because thedilution herein required will impede the chemical reactionrequired for these types of coatings.1.4 This method can be used to determine the weightpercent organic cont
5、ent of waterborne coatings in which thevolatile organic compound weight percent is below 5 percent.The method has been used successfully with higher contentwaterborne coatings and with solventborne coatings (Note 2).1.5 This method may also be used to measure the exemptvolatile organic compound cont
6、ent (for example, acetone,methyl acetate, t-butyl acetate and p-chlorobezotrifluoride) ofwaterborne and solvent-borne coatings. Check local regula-tions for a list of exempt compounds. The methodology isvirtually identical to that used in Test Method D6133 which, aswritten, is specific for only exem
7、pt volatile compounds.1.6 Volatile compounds that are present at the 0.005 weightpercent level (50 ppm) or greater can be determined. Aprocedure for doing so is given in Section 9.1.7 Volatile organic compound content of a coating can becalculated using data from Test Method D6886 but requiresother
8、data (see Appendix X2.)NOTE 1Data from this method will not always provide the volatileorganic compound content of a paint film equivalent of EPA Method 24.Some compounds and some semi-volatile compounds may be consideredvolatile using the GC conditions specified but will not fully volatilizeduring
9、the one hour at 110C conditions of EPA Method 24. Some or allof these materials remain in the paint film and therefore are not consideredvolatile organic compounds according to EPA Method 24. In addition,some compounds may decompose at the high inlet temperature of the GC.However, note the EPAMethod
10、 24 has poor precision and accuracy at lowlevels of volatile organic compounds.NOTE 2This method measures volatile organic compound weight ofair-dry coatings directly as opposed to other methods in Practice D3960which measure the volatile organic compound weight percent indirectly.Adirect measuremen
11、t of the weight percent particularly in low volatileorganic compound content waterborne coatings, generally gives betterprecision. California Polytechnic State University carried out an extensivestudy for the California Air Resources Board comparing the precision ofthe direct method with the indirec
12、t method (CARB Standard AgreementNo. 04.329) Detailed results of this study may be found at http:/www.arb.ca.gov/coatings/arch/Final_Report_6_11_09.pdf. This studymay be used to decide if the present method or other methods in PracticeD3960 are preferred for a specific coating.1.8 The values stated
13、in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.1.9 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 he
14、alth practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D1475 Test Method For Density of Liquid Coatings, Inks,and Related ProductsD2369 Test Method for Volatile Content of CoatingsD3792 Test Method for Water Content of Coatin
15、gs by DirectInjection Into a Gas ChromatographD3925 Practice for Sampling Liquid Paints and Related1This test method is under the jurisdiction of ASTM Committee D01 on Paintand Related Coatings, Materials, and Applications and is the direct responsibility ofSubcommittee D01.21 on Chemical Analysis o
16、f Paints and Paint Materials.Current edition approved June 15, 2014. Published July 2014. Originallyapproved in 2003. Last previous edition approved in 2012 as D6886 12. DOI:10.1520/D6886-14E01.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at s
17、erviceastm.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 States1Pigmented CoatingsD3960 Practice for Determining Vola
18、tile Organic Compound(VOC) Content of Paints and Related CoatingsD4017 Test Method for Water in Paints and Paint Materialsby Karl Fischer MethodD6133 Test Method for Acetone, p-Chlorobenzotrifluoride,Methyl Acetate or t-Butyl Acetate Content of Solvent-borne and Waterborne Paints, Coatings, Resins,
19、and RawMaterials by Direct Injection Into a Gas ChromatographD7358 Test Method for Water Content of Paints by Quanti-tative Calcium Hydride Reaction Test KitE177 Practice for Use of the Terms Precision and Bias inASTM Test MethodsE691 Practice for Conducting an Interlaboratory Study toDetermine the
20、Precision of a Test Method2.2 Other Documents:EPAMethod 24 Determination of Volatile Matter Content,Water Content, Density, Volume Solids, and Weight Solidsof Surface Coatings40 CFR 51.100 (s) List of components that EPA has classi-fied as VOC-exempt3. Terminology3.1 Acronyms:3.1.1 EGDEethylene glyc
21、ol diethyl ether3.1.2 DB2-(2-butoxyethoxy)ethanol; Butyl Carbitol;3di-ethylene glycol monobutyl ether3.1.3 EB2-butoxyethanol; Butyl Cellosolve;4ethyleneglycol monobutyl ether3.1.4 EGethylene glycol3.1.5 FIDflame ionization detector3.1.6 GCgas chromatograph3.1.7 PGpropylene glycol3.1.8 SPMEsolid phas
22、e microextraction3.1.9 SPDEsolid phase dynamic extraction3.1.10 TMPD-IB2,2,4-trimethypentane-1,3-diol,monoisobutyrate3.1.11 TMPD-DIB2,2,4-trimethypentane-1,3-diol, di-isobutyrate3.1.12 VOCvolatile organic compound used in various airquality regulations4. Summary of Test Method4.1 A known weight of c
23、oating is dispersed in methanol ortetrahydrofuran (THF) internally standardized, and analyzedby capillary gas chromatography to give a speciated composi-tion of the volatile organic compounds (Note 3). Summation ofthe individual volatile organic compound weight percents givesthe total volatile organ
24、ic content of the coating measured inweight percent.NOTE 3Methanol can be used as a first choice as a solvent for allwaterborne coatings. THF can be used for solventborne coatings. Acetonemay also be used for solventborne coatings but should not be used forwaterborne coatings because it may react wi
25、th ammonia and amines whichare frequently found in waterborne coatings. Other solvents can be used ifneeded but the choice of solvent should be reported.4.2 Direct GC/FID, GC/MS and solid phase microextraction/ gas chromatography (SPME/GC) of the coating may be usedto facilitate identification of th
26、e volatile compounds present ina coating (Note 4). Table X1.1 lists the GC retention times forsome of the volatile compounds which may be found in lowvolatile organic compound content air-dry coatings and forseveral possible internal standards, ordinarily not present incoatings, which may be used (N
27、ote 4).NOTE 4The analyst should consult MSDS and product data sheets forinformation regarding solvents which are expected in a particular coating.Additional solvents, not shown on the MSDS or PDS may also be presentin the coating. Retention times given in Appendix X1 must be verified foreach individ
28、ual instrument.NOTE 5The accuracy of the volatile organic compound weightpercent determined using Test Method D6886 is dependent on the properidentification of the compounds detected in the chromatogram. Theresponse of the flame ionization detector (FID) used in the GC isdependent on the compound de
29、tected. The accuracy of the determinationrequires proper identification (by GC/MS, by retention time, or byanalyzing the sample on a GC column with a different stationary phase)and calibration of the GC for the compounds detected.5. Significance and Use5.1 In using Practice D3960 to measure the vola
30、tile organiccompound content of waterborne coatings, precision can bepoor for low volatile organic compound content air-dry coat-ings if the volatile organic weight percent is determinedindirectly. The present method directly identifies and thenquantifies the weight percent of individual volatile or
31、ganiccompounds in air-dry coatings (Note 6). The total volatileorganic weight percent can be obtained by adding the indi-vidual weight percent values (Note 7).NOTE 6The present method may be used to speciate solvent-borneair-dry coatings. However, since these normally contain high, and oftencomplex,
32、 quantities of solvent, precision tends to be better using othermethods contained in Practice D3960, where the volatile fraction isdetermined by a direct weight loss determination.NOTE 7Detectable compounds may result from thermal decomposi-tion in a hot injection port or from reaction with the extr
33、action solvent. Ifit can be shown that a material is a decomposition product, or is the resultof a reaction with the extraction solvent, then results for that compoundshould be discounted from the volatile measured by Test Method D6886.6. Apparatus6.1 Gas Chromatograph, FID Detection or Mass Spectro
34、m-etry Detection with Electronic Data Acquisition SystemAnycapillary gas chromatograph equipped with a flame ionizationdetector or mass spectrometer and temperature programmingcapability may be used. Electronic flow control, which gives aconstant carrier gas flow, is highly recommended. Note thatpre
35、cision and accuracy have only been evaluated using GCwith FID detection.3Butyl Carbitol is a registered trademark of The Dow Chemical Company.4Butyl Cellosolve is a registered trademark of The Dow Chemical Company.D6886 14126.2 Standard GC/FID and GC/MS Instrument Conditions:Instrument Conditions FI
36、D GC/MSDetector Flame ionization 70 eV electron impact massspectrometerColumns Primary column:30 by 0.25 mm5 % phenyl/95 % methylsiloxane (PMPS),A1.0 m film thicknessPrimary column:30 by 0.25 mm% phenyl/95 % methylsiloxane (PMPS),A1.0 m film thicknessConfirmatory Columns:30 by 0.25 mmpolydimethylsil
37、oxane (PDMS),0.25 m film thickness;30 by 0.25 mmCarbowax (CW),0.25 m film thickness.Confirmatory Columns:30 by 0.25 mmpolydimethylsiloxane (PDMS),0.25 m film thickness;30 by 0.25 mmCarbowax (CW),0.25 m film thickness.Carrier Gas Helium HeliumFlow Rate 1.0 mL per min,constant flow(24.9 cm/s at 40)1.0
38、 mL per min,constant flow(24.9 cm/s at 40)Split Ratio 50 to 1 50 to 1Temperatures, C,Primary ColumnInlet 260 260Detector 270 270Initial 50 for 4 min 50 for 4 minRate 20 per min to 250,hold 6 min (total run time = 20 min)20 per min to 250,hold 6 min (total run time = 20 min)Temperatures, C,Confirmato
39、ry ColumnsInlet 260 260Detector 270 270Initial 40 for 4 min 40 for 4 minRate 10 per min to 250, hold 25min 10 per min to 250, hold 25minSource 230Quadrupole 230Transfer Line 260Scanning Parameters Mass 29400 amuAThe column designated as PMPS is commercially available from several vendors by the foll
40、owing designations: DB-5, SPB-5, HP-5, AT-5, CP Sil 8 CB, RTx-5, BP-5.The column designated as PDMS is available by the designations DB-1, SPB-1, HP-1, AT-1, CP Sil 5 CB, Rtx-1. The column designated as Carbowax is available by thedesignations Supelcowax 10, DB-Wax, HP-Wax, AT-Wax, CP-Wax 52 CB, Rtx
41、-Wax, BP-20.NOTE 8Some coatings may contain high-boiling components whichelute from the GC capillary column after the specified run time of 20 min.It is advisable, therefore, to bake out the column between runs in thesecases.7. Reagents and Materials7.1 Purity of ReagentsReagent grade chemicals shal
42、l 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 of sufficiently high purity to permit its
43、 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 Methanol, HPLC grade.7.5 Possible internal standards: 1-Propanol,p-fluorotoluene, cyclohexanol, p-chlorotoluene, ethylene glycoldiethylether (EGDE).7
44、.6 Fluorocarbon-faced Septum Vials, 20 mL and 40 mLcapacity.7.7 Ceramic Beads, 0.51.0 mm diameter.8. Column Conditioning8.1 The capillary columns should be conditioned accordingto the manufacturers recommendation. The columns may thenbe used indefinitely without further conditioning.9. Preparation o
45、f Standards9.1 Prepare a stock mixture of ethylene glycol (EG), pro-pylene glycol (PG), ethylene glycol monobutyl ether (EB),ethylene glycol diethyl ether (EGDE) or other suitable internalstandard, diethylene glycol monobutyl ether (DB), and 2,2,4-trimethylpentane-1,3-diol monoisobutyrate (TMPD-IB)
46、byweighing one or two grams of each into an appropriate vial.The weight of each component should be approximately thesame and determined 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 or methanol andmix the contents (N
47、ote 9). This solution will contain each ofthe known analytes at a concentration of approximately 2mg/mL.NOTE 9The solvents EG, PG, EB, DB TMPD-IB are widely used inthe manufacture of waterborne air-dry coatings and may be expected asprobable components of these coatings.9.3 Chromatograph the solutio
48、n in 9.2 by injecting 1 L intothe PMPS column using the chromatographic conditions givenin 6.2. Calculate the relative response factors for each of theD6886 1413analytes relative to the EGDE or other suitable internalstandard using the relationship:RF 5AA*MIAI*MA(1)where:RF = relative response facto
49、r,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 Analysis of Air-dry Solvent-borne and WaterborneCoatings by GC/FID:10.1.1 Prepare duplicate samples by pipetting 10 mL ofmethanol (waterborne coatings) or THF (solventborne coat-ings) into a vial containing 3 to5gofceramic beads and closewith a fluorcarbon-faced septum cap. Using a dedicated glasssyringe (25 or 50 microliter capacity), add 10 L of EGDE o
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