1、Designation: D 2245 90 (Reapproved 2005)Standard Test Method forIdentification of Oils and Oil Acids in Solvent-ReduciblePaints1This standard is issued under the fixed designation D 2245; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revis
2、ion, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defense.1. Scope1.1 This test method co
3、vers the identification 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 and veg-etable, unpolymerized o
4、r partially polymerized 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 the
5、safety 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. Referenced Documents2.1 ASTM Standards:2D 1398 Test Method for Fatty
6、 Acid Content of AlkydResins and Alkyd Resin SolutionsD 1983 Test Method for Fatty Acid Composition by Gas-Liquid Chromatography of Methyl EstersD 2372 Practice for Separation of Vehicle from Solvent-Reducible PaintsD 2800 Test Method for Preparation of Methyl Esters fromOils for Determination of Fa
7、tty Acid Composition byGas-Liquid Chromatography3. 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 gas chromatographic col
8、umn. 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 saponification, conversion of fatt
9、y 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, reported as i
10、s, 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, high-speed, capable of developing in excessof 10 000 g.5.2
11、Separatory Funnels, with PTFE-fluorocarbon stop-cocks.5.3 Gas Chromatograph and Accessories, suitable foranalysis of fatty acids as methyl esters (see Test MethodD 1983).6. Reagent6.1 Hydroquinone.7. Calibration and Standardization7.1 Establish optimum operating conditions on the gaschromatograph wi
12、th known samples of methyl esters as de-scribed in Test Method D 1983.1This 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 Chemical Analysis of Paints and Paint Materials.
13、Current edition approved Jan. 1, 2005. Published February 2005. Originallyapproved in 1964. Last previous edition approved in 1999 as D 2245 90 (1999).2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStan
14、dards volume information, refer to the standards Document Summary page onthe ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.7.2 Prepare working standards by running known paints orvehicles through the procedure describe
15、d in Section 8. Includeparticularly 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 direct high-speedcentrifuging (
16、see Practice D 2372).TABLE 1 Fatty Acid Composition of Oils Used in Paint ProductsACaster Oil, % Oiticica Oil,%Palmitic 2 Palmitic 7Stearic 1 Stearic 5Oleic 7 Oleic 6Ricinoleic 87 Licanic 78Linoleic 3 Hydroxy acids 4Coconut Oil,% Perilla Oil,%Caproic trace Palmitic 7Caprylic 6 Stearic 2Capric 6 Olei
17、c 13Lauric 44 Linoleic 14Myristic 18 Linolenic 64Palmitic 11 Safflower Oil,%Stearic 6 Myristic traceOleic 7 Myristoleic traceLinoleic 2 Palmitic 8Linolenic trace Palmitoleic traceCottonseed Oil,% Stearic 3Capric trace Oleic 13Lauric trace Linoleic 75Myristic 1 Linolenic 1Myristoleic trace Arachidic
18、tracePalmitic 29 Gadoleic tracePalmitoleic 2 Soybean Oil,%Stearic 4 Myristic traceOleic 24 Palmitic 11Linoleic 40 Stearic 4Arachidic trace Oleic 25Linseed Oil,% Linoleic 51Palmitic 6 Linolenic 9Palmitoleic trace Arachidic traceStearic 4 Gadoleic traceOleic 22 Tall Oil,B%Linoleic 16 Palmitic 5Linolen
19、ic 52 Stearic 3Arachidic trace Oleic 46Gadoleic trace Linoleic 41Menhaden Oil,% Linolenic 3Lauric trace Arachidic 2Myristic 7 Tung Oil,%Myristoleic trace Palmitic 4Palmitic 16 Stearic 1Palmitoleic 16 Oleic 8Stearic 2 Linoleic 4Oleic 15 Linolenic 3Linoleic 7 Eleostearic 80Linolenic 2Arachidonic 17Clu
20、panodonic 11Nisinic 4Shibic 1Unidentified unsaturate 2AThe acids and percents presented in this table are taken from the “Composition and Constants of Fatty Acids” chart and used by permission of theArcher-Daniels-Midland Co.BThe percent rosin acids in tall oil may vary from 0 to 42 %, the percent t
21、erpenes from 0 to 13 %. Both variations depend on the grade and refining of the oil.D 2245 90 (2005)28.2 Extract the fatty acids from the separated vehicle aftersaponification and removal of the dicarboxylate salts andunsaponifiable matter in accordance with Test Method D 1398,but substitute separat
22、ory 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 the Procedure Section, MethodB, of Test Met
23、hod D 1398. Swirl the flask containing the fattyacids, some ether solvent, and the hydroquinone until thehydroquinone is well dispersed; evaporate off the remainingether carefully under vacuum as described in Test MethodD 1398. Analyze immediately or store for only a limited timein a small tall form
24、 vial under nitrogen in a dark cool place.8.3 Prepare methyl esters of the extracted fatty acids inaccordance with the Procedure Section of Test Method D 2800.8.4 Determine the fatty acid composition in accordance withTest Method D 1983. (See Appendix, Fig. X1.1, for a typicalchromatogram prepared i
25、n accordance with Test MethodD 1983).8.5 Compare the chromatogram or fatty acid composition,or both, with the chromatograms or fatty acid compositions, orboth, of suspected known materials (See Table 1, for typicalfatty acid compositions of oils used in paint products). Con-sider the content of spec
26、ific fatty acids characteristic of specificoils. Consider the total saturates versus unsaturates and poly-mer content in relation to what the original starting oil or oilacids might have been.9. Report9.1 Report the type of oil or oil acid when the fatty aciddistribution approximates a specific know
27、n distribution orcombination, when the limit of the possibilities is known andwhen the polymer content can be explained. (SeeAppendix X1for some of the considerations in interpreting the analysisresults).9.2 Even when the identification is positive, it is recom-mended that the actual percent distrib
28、utions of monomeric fattyacids and the polymer content be reported. In very complexsystems where the possible combinations are too numerous toallow an immediate identification, the percent breakdownfigures should be recorded. Considered with other data thatmight subsequently be obtained, the fatty a
29、cid and polymerdistribution can be important.10. Precision10.1 Single-oil types have been correctly identified in col-laborative work for seven round-robin samples. Representedwere four linseed types, three soya types, one fish oil type, andone coconut type.11. Keywords11.1 fatty acids; oils; oil ac
30、ids; solvent-reducible paintsAPPENDIX(Nonmandatory Information)X1. CONSIDERATIONS IN THE INTERPRETATION OF FATTY ACID COMPOSITIONX1.1 In the determination of the identity of pure naturaloils, the percent breakdown of the fatty acids will many timessuffice for oil identification. When a mixture of oi
31、l or oil-acidtypes is suspected, one can profit by comparing the content ofkey fatty acids. For example, a high oleate content in whatotherwise appears to be a soya-type composition would suggestsoya plus some tall oil. If, however, the palmitate appears alittle high, one would conclude that some co
32、ttonseed had beenadded to the soya-type acids. Theoretically, if it can beestablished that the system under study is derived from alimited number of oil types on which exact fatty acid distribu-tions are known, and polymerization or isomerization is notinvolved, a strictly mathematical approach to d
33、etermining thequantity of each oil type is feasible. By means of a set ofsimultaneous equations involving key acids such as oleate,linoleate, linolenate, and stearate one should expect to be ableto estimate mixtures of two or possibly three oil types.X1.2 In the event that chromatographic analysis s
34、uggeststhe presence of polymer, it must be known that the polymercomposition is due solely to oil polymer if the calculation ofpolymer content is to be of value in oil identification. In suchcases the polymer content of the oil-ester sample plus thepercent of the polyunsaturated acids obtained from
35、the chro-matogram (see Fig. X1.1) can be used to determine the totalpolyunsaturates present in the original oil. Since the value fortotal polyunsaturates varies with the oil in question, theexperimental value obtained is used as additional evidence foroil identification.X1.3 The presence of oil poly
36、mer composed of reactionproducts of oil acids with cyclo- or dicyclopentadiene, maleicFIG. X1.1 Drying-Oil Methyl EstersD 2245 90 (2005)3anhydride, styrene vinyltoluene, or other Diels-Alder adducts,or the presence of rosin acids (in the case of tall oil fatty acidswith high rosin content), negate t
37、he value of percent polymerdeterminations for assistance in oil identification. In mostcases, the presence of these modifications can be detected byrunning infrared spectra on a portion of the separated fattyacids. As more work is done using the quantitative internalstandard technique, it is expecte
38、d that the data accumulatedwill aid everyone in interpreting what is involved in some ofthe observed polymer content results.X1.4 Another more direct interference, which has not beenmentioned, is the presence of carboxylic acid esters other thanfatty acids. Acids such as isophthalic and benzoic acid
39、 areexpected to be present in the fatty acid fraction due to thepartial solubility of their potassium salts in the saponificationmedium. This is the main reason for using anhydrous reagentsfor the saponification of alkyds or polyesters. When unfamiliarpeaks are observed in the chromatogram of fatty
40、acid methylesters from whole paint, this type of interference should beconsidered.ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the v
41、alidity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your c
42、omments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments ha
43、ve not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).D 2245 90 (2005)4
