1、Designation:D224590(Reapproved 2011)Standard Test Method forIdentification of Oils and Oil Acids in Solvent-ReduciblePaints1This standard is issued under the fixed designation D2245;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the
2、 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.This standard has been approved for use by agencies of the U.S.Department of Defense.1.Scope1.1 This test method covers the i
3、dentification of oils and oilacids in vehicles that have been separated from solvent-reducible paints.The test method is based on a gas chromato-graphic technique(of the methyl esters)applicable to productscontaining both saturated and unsaturated,animal andvegetable,unpolymerized or partially polym
4、erized fatty acidshaving 8 to 20 carbon atoms.1.2 This test method is not applicable to products containingfatty acids that have been polymerized or oxidized to such anextent that no characteristic monomeric fatty acids remain.1.3 This standard does not purport to address all of thesafety concerns,i
5、f 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.Referenced Documents2.1 ASTM Standards:2D1398 Test Method for Fatty Acid Content of Alkyd
6、 Resinsand Alkyd Resin Solutions(Withdrawn 2007)3D1983 Test Method for Fatty Acid Composition by Gas-Liquid Chromatography of Methyl Esters(Withdrawn2003)3D2372 Practice for Separation of Vehicle From Solvent-Reducible PaintsD2800 Test Method for Preparation of Methyl Esters FromOils for Determinati
7、on of Fatty Acid Composition byGas-Liquid Chromatography(Withdrawn 2007)33.Summary of Test Method3.1 This test method is based upon the differential migrationand partitioning of constituent fatty acids in the form ofvaporized methyl esters between a flowing gas phase and asupported liquid phase in a
8、 gas chromatographic column.Thetest method is based on isothermal operation of the gaschromatograph and a hot wire,thermal conductivity detector.3.2 The test method consists in the separation of the vehiclefrom the paint by centrifugation,extraction of fatty acids fromthe vehicle after saponificatio
9、n,conversion of fatty acids and ameasured addition of margaric acid(internal standard)intomethyl esters,preparation of the gas chromatogram,andinterpretation of the chromatogram.The amount of eachmonomeric fatty acid ester is calculated,totaled,subtractedfrom 100%to yield polymerized fatty acids,rep
10、orted as is,andinterpreted by comparison with standards as being fromspecific oils or oil acids.4.Significance and Use4.1 This test method provides a procedure to identify thefatty acids present in the vehicle of a paint.5.Apparatus5.1 Centrifuge,5.2 Separatory Funnels,with PTFE-fluorocarbon stop-co
11、cks.5.3 Gas Chromatograph and Accessories,suitable foranalysis of fatty acids as methyl esters(see Test MethodD1983).6.Reagent6.1 Hydroquinone.7.Calibration and Standardization7.1 Establish optimum operating conditions on the gaschromatograph with known samples of methyl esters as de-scribed in Test
12、 Method D1983.7.2 Prepare working standards by running known paints orvehicles through the procedure described in Section 8.Include1This test method is under the jurisdiction of ASTM Committee D01 on Paintand Related Coatings,Materials,and Applications and is the direct responsibility ofSubcommittee
13、 D01.21 on Chemical Analysis of Paints and Paint Materials.Current edition approved June 1,2011.Published June 2011.Originallyapproved in 1964.Last previous edition approved in 2005 as D2245 90(2005).DOI:10.1520/D2245-90R11.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact
14、 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 approved version of this historical standard is referenced onwww.astm.org.Copyright ASTM International,100 Barr Harbor Drive,PO Box
15、C700,West Conshohocken,PA 19428-2959.United States1 particularly compositions with chemical or structural modifi-cations that might be expected to alter the fatty acid distribu-tion or the apparent polymer content of the starting rawmaterials.8.Procedure8.1 Separate the vehicle from the paint by dir
16、ect high-speedcentrifuging(see Practice D2372).8.2 Extract the fatty acids from the separated vehicle aftersaponification and removal of the dicarboxylate salts andunsaponifiable matter in accordance with Test Method D1398,but substitute separatory funnels with PTFE-fluorocarbon stop-cocks when available.In cases involving unsaturated fattyacids,add a crystal or diethyl ether solution of hydroquinone(equivalent to less than 0.05 weight%of the fatty acids to thefatty acid fractions obtained in th
