1、Designation: D4457 02 (Reapproved 2014)Standard Test Method forDetermination of Dichloromethane and 1,1,1-Trichloroethanein Paints and Coatings by Direct Injection into a GasChromatograph1This standard is issued under the fixed designation D4457; the number immediately following the designation indi
2、cates 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
3、of totalamount of dichloromethane or 1,1,1-trichloroethane, or both, inpaints and coatings. It has been evaluated for cellulose nitrate,alkyd, vinyl, and styrene-butadiene systems. It has not yet beenevaluated for other formulations, but is believed to be appli-cable. The established working range o
4、f this test method isfrom 31 to 65 % for 1,1,1-trichloroethane and 32 to 78 % fordichloromethane. There is no reason to believe it will not workoutside of these ranges. The presence of 1-propanol in paintsand coatings requires the use of a different internal standard.(See also Practice E260.)1.2 The
5、 values stated in inch-pound units are to be regardedas standard. The values given in parentheses are mathematicalconversions to SI units that are provided for information onlyand are not considered standard.1.3 This standard does not purport to address all of thesafety concerns, if any, associated
6、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. Specific hazardstatements are given in Section 7.2. Referenced Documents2.1 ASTM Standards:2E180 Practice
7、for Determining the Precision of ASTMMethods for Analysis and Testing of Industrial and Spe-cialty Chemicals (Withdrawn 2009)3E260 Practice for Packed Column Gas Chromatography3. Summary of Test Method3.1 Anhydrous 1-propanol (see 10.5) is added as an internalstandard to suitable aliquot of the whol
8、e paint. The aliquot isthen diluted with dimethylformamide and injected onto a gaschromatographic column containing a porous polymer packingthat separates dichloromethane and 1,1,1-trichloroethane fromother volatile compounds.4. Significance and Use4.1 Use of 1,1,1-trichloroethane and dichloromethan
9、e,which do not measurably contribute to the atmospheric oxidantlevel, is a way for industry to meet government or otherregulations on volatile organic compounds. This test method isdesigned to determine the content of these halohydrocarbonsolvents in paints and coatings. That content can subsequentl
10、ybe used in calculating the volatile organic compound content ofa coating.5. Apparatus5.1 Chromatograph, any gas-liquid chromatographic instru-ment equipped with a thermal conductivity detector andcapable of being temperature programmed (see Table 1).Optionally, a flame ionization detector may be us
11、ed if thesample is diluted so that no more than 1000 ppm each ofdichloromethane and 1,1,1-trichloroethane is present in theinjected specimen.5.2 Recorder, a recording potentiometer with a full-scaledeflection of 10 mV, a full-scale response time of 2 s or less,and a maximum noise of 60.03 % of full
12、scale.5.3 Pre-Column, 40 in. (100 mm) long by18 in. (3.2 mm)outside diameter stainless steel, packed with glass wool, fittedon the entrance end of the column to retain any nonvolatilematerials and minimize sludge buildup in the column.5.4 Column, 4 ft (1.22 m) long by18 in. (3.2 mm) outsidediameter
13、stainless steel, packed with 80/100 mesh (150 to180 m) porous polymer packing material,4or other suitablematerial.1This 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 Chem
14、ical Analysis of Paints and Paint Materials.Current edition approved July 1, 2014. Published July 2014. Originally approvedin 1985. Last previous edition approved in 2008 as D4457 02 (2008). DOI:10.1520/D4457-02R14.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM
15、Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3The last approved version of this historical standard is referenced onwww.astm.org.4Porapak R, a registered trademark of Waters Associates, Inc.,
16、 Milford, MA, hasbeen found satisfactory for this purpose.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States15.5 Liquid Charging Devices, such as microsyringes of 5-Lor 10-L capacity, cleaned with acetone or other suitablesolvent. Visual
17、ly inspect for plugs or cracks before and aftereach injection.5.6 Vials, 25-mL to minimize head space, capable of beingseptum sealed.56. Reagents and Materials6.1 Purity of ReagentsReagent grade chemicals shall beused in all tests, unless otherwise specified (as in 6.7). Unlessotherwise indicated, i
18、t is intended that all reagents shallconform to the specifications of the Committee on AnalyticalReagents of the American Chemical Society, where suchspecifications are available.6Other grades may be used pro-vided it is first ascertained that the reagent is of sufficient highpurity to permit its us
19、e without lessening the accuracy of thedetermination.6.2 Carrier Gas, helium of 99.995 % or higher purity. Highpurity nitrogen may also be used.6.3 Dimethylformamide (DMF), reagent grade.6.4 1-Propanol, gas chromatography spectrophotometricquality (see 10.5).6.5 1,1,1-Trichloroethane (see 6.7).6.6 D
20、ichloromethane (see 6.7).6.7 Halogenated Hydrocarbon StabilizersAll commercialgrades of these halogenated hydrocarbons contain stabilizers.Either obtain the same solvent used in the coating for use as thestandard, or find the type and quantity of stabilizer specified foruse in the solvent of interes
21、t and add the appropriate quantityto the pure solvent.7. Hazards7.1 Dimethylformamide is harmful if inhaled or absorbedthrough skin. Use only with adequate ventilation. Avoidcontact with skin, eyes, and clothing.8. Preparation of Apparatus8.1 Column ConditioningThe packed column is installedin the g
22、as chromatographic unit leaving the exit end discon-nected from the detector. This will prevent any contaminationof the detector with the column bleed. Set the helium flow rateat 30 mL/min if a18 in. (3.2 mm) outside diameter column isused. Purge the column 5 to 10 min before heating. Heat thecolumn
23、 from room temperature to 200C at 5C/min and holdthis temperature for at least 12 h (overnight). At the end of thisperiod of time, heat the column to 240C at a 5C/min rate andhold this temperature for several hours. The maximum tem-perature for this packing is 250C. Cool the column to 100Cand reheat
24、 to 240C at 5C/min to observe the column bleed.Optimum conditioning of this column may take several cyclesof the heating program before a good recorder baseline isachieved. Conditioning of any column other than that sug-gested (5.4) should be in accordance with the manufacturersrecommendations.8.2 I
25、nstall the column in the chromatograph and use theinformation in Table 1 as a guide to establish the conditionsrequired to give the desired separation. Allow sufficient timefor the instrument to reach equilibrium as indicated by a stablerecorder baseline.Adjust the carrier-gas flow to a constant rat
26、e.Before each calibration and series of determinations (or daily),condition the column at 200C for 1 h with carrier-gas flow.9. Calibration9.1 Preparation of StandardsAll standards, as well assamples and blanks, should be at a constant temperature. Thegiven order of ingredient addition should be obs
27、erved tominimize loss of volatile ingredients.9.1.1 Weighing to 1.0 mg, add 16.0 g of dimethylformamideto a vial capable of being septum sealed. Add 2.0 g of1,1,1-trichloroethane, 2.0 g of 1-propanol (see 10.5) and 2.0 gof dichloromethane. Seal the vial with a crimp-on or septumseal.9.2 Determine th
28、e retention time of each component byinjecting small amounts either separately or in known mix-tures. The components should elute close to the typicalretention times given in Table 1 and the chromatograms shouldclosely approximate those shown in Fig. 1.9.3 The area under each peak of the chromatogra
29、m isconsidered a quantitative measure of the corresponding com-pound. The relative area is proportional to concentration if thedetector responds equally to all the sample components. Theresponse to different components is generally significantlydifferent for both flame ionization and thermal conduct
30、ivitydetectors and especially for flame ionization detectors. Thisdifference in detector response may be corrected by use ofrelative response factors obtained by injecting and measuringthe response of known blends. For precise and accuratedetermination of the halogenated hydrocarbons injecta1Lspecim
31、en of the standard in accordance with the preparation in9.1. Calculate the response factors relative to unity for thehalogenated hydrocarbons.5Miniert valves, available from The Pierce Chemical Co., Box 117, Rockford, IL61105, have been found satisfactory for this purpose.6Reagent Chemicals, America
32、n Chemical Society Specifications, AmericanChemical Society, Washington, DC. For suggestions on the testing of reagents notlisted by the American Chemical Society, see Analar Standards for LaboratoryChemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeiaand National Formulary, U
33、.S. Pharmacopeial Convention, Inc. (USPC), Rockville,MD.TABLE 1 Typical Instrument ConditionsDetector thermal conductivityColumn 4 ft (1.22 m) by18 in. (3.2 mm) outsidediameter packed with 80100 meshporous polymer packingTemperature, CInjection port 200Detector block 250ColumnInitial 100Final 230 (f
34、or 8 min)C/min 8Carrier gas heliumFlow rate, mL/min 30Specimen size, L 1D4457 02 (2014)210. Procedure10.1 Keep all samples, blanks, and standards at a constanttemperature. Observe the given order of ingredient addition tominimize loss of volatile ingredients. Shake paints, thensample from the middle
35、 of the container.10.2 Weighing to 1.0 mg, add 16.0 g of dimethylformamideand 5.0 g of the paint to a vial capable of being septum sealed.Add 2.0 g of 1-propanol (see 10.5). Seal the vial with acrimp-on or septum seal.10.3 Shake the vial. Then to facilitate settling, centrifugeusing a low speed cent
36、rifuge at 1000 rpm for 5 min.10.4 Inject a 1-L specimen of the supernatant from theprepared solution onto the chromatographic column, in accor-dance with the conditions established in 8.2. Record the peaksof all components.10.5 If the composition of the paint is unknown, test for thepresence of 1-pr
37、opanol. Prepare a blank, omitting the 2.0 g of1-propanol in 10.2, and inject a 1-L specimen. To this blankadd 2.0 g of 1-propanol and inject a 1-L specimen. Thencompare peak response to that from the test solution. If1-propanol is present in the paint, substitute a different internalstandard. Other
38、possible internal standards include alcohols,esters, and hydrocarbons.10.6 If the composition of the paint is unknown, establishwhether peaks interfering with 1-propanol or the halogenatedhydrocarbons are present by using both the column specified in5.4 and a second column that yields different rete
39、ntion times.711. Calculation11.1 Measure the area of all peaks (Note 1) and multiplyeach area by the appropriate attenuation factor to express thepeak areas on a common basis.NOTE 1Peak areas may be determined by any method that meets theprecision requirements of Section 12. Electronic integration i
40、s recom-mended for best results.11.2 Calculate the percent halogenated hydrocarbon in thepaint as follows:RFi5WiAi(1)where:RFi= corrected peak response for ithcomponent, area units,Wi= weight of ithcomponent in the standard solution, g,andAi= chromatographic peak area for the ithcomponent inthe stan
41、dard solution, area units,then:CH wt% 5RFCH3 ACH3 ISamtRFIS3 AIS3 W3100 (2)where:CH wt % = chlorinated hydrocarbon, weight %,RFCH= response factor for the chlorinated hydrocarbonin the standard solution, area units,ACH= area of the chlorinated hydrocarbon peak in thetest solution, area units,ISamt=
42、weight of internal standard added to the paint,g,RFIS= response factor for the internal standard in thestandard solution, area units,AIS= area of the internal standard peak in the testsolution, area units, andW = specimen weight, g.12. Precision and Bias8(see also Practice E180)12.1 Precision:12.1.1
43、 1,1,1-TrichloroethaneOn the basis of an interlabo-ratory test of this test method in which one operator in each ofeight laboratories tested three coatings containing from 31 to65 % 1,1,1-trichloroethane (theoretical), the within-laboratorycoefficient of variation was found to be 1.01 % relative at
44、207Packings from the Porapak series and the Chromosorb Century series may besatisfactory for this purpose. However, it is the responsibility of each analyst tocheck for interferences from paints or the internal standard chosen, or both, and tochoose a column that gives symmetrical peaks.8Supporting
45、data have been filed at ASTM International Headquarters and maybe obtained by requesting Research Report RR:D01-1045. ContactASTM CustomerService at serviceastm.org.FIG. 1 Typical Chromatograms of PaintsD4457 02 (2014)3degrees of freedom and the between-laboratories coefficient ofvariation was found
46、 to be 2.72 % relative at 17 degrees offreedom. Based on these coefficients, the following criteriashould be used for judging the acceptability of results at the95 % confidence level:12.1.1.1 RepeatabilityTwo results, each the mean of du-plicate runs, obtained by the same operator should be consid-e
47、red suspect if they differ by more than 3.0 % relative.12.1.1.2 ReproducibilityTwo results, each the mean ofduplicate runs, obtained by operators in different laboratoriesshould be considered suspect if they differ by more than 8.1 %relative.12.1.2 DichloromethaneOn the basis of an interlaboratoryte
48、st of this test method in which one operator in each of eightlaboratories tested two coatings containing from 32 to 78 %dichloromethane (theoretical), the within-laboratory coefficientof variation was found to be 0.98 % relative at 14 degrees offreedom and the between-laboratories coefficient of var
49、iationwas found to be 5.16 % relative at 12 degrees of freedom.Based on these coefficients, the following criteria should beused for judging the acceptability of results at the 95 %confidence level:12.1.2.1 RepeatabilityTwo results, each the mean of du-plicate runs, obtained by same operator should be consideredsuspect if they differ by more than 3.0 % relative.12.1.2.2 ReproducibilityTwo results, each the mean ofduplicate runs, obtained by operators in different laboratoriesshould be considered suspect if they differ by more than17.92 % relati
