1、Designation: D5774 95 (Reapproved 2014)Standard Test Methods forRubberChemical Analysis of Extractables1This standard is issued under the fixed designation D5774; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last rev
2、ision. 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 These test methods cover the chemical analysis ofextractables from synthetic rubbers and are intended forgeneral use on solid
3、uncompounded styrene-butadiene copoly-mers commonly referred to as SBR.Analysis of other syntheticrubbers is also possible with some of these test methods. Thetest methods and the sections in which they are covered are asfollows:SectionsTotal Extractables 411Organic Acid 1219Soap 2026Oil 2742NOTE 1T
4、he nomenclature used in these test methods is in accordancewith Practice D1418.1.2 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 dete
5、rmine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D297 Test Methods for Rubber ProductsChemical Analy-sisD1418 Practice for Rubber and Rubber LaticesNomenclatureD4483 Practice for Evaluating Precision for Test MethodStandards in the Rubber and
6、 Carbon Black ManufacturingIndustries3. Reagents3.1 Purity of ReagentsReagent grade chemicals shall beused in all tests. Unless otherwise indicated, it is intended thatall reagents conform to the specifications of the Committee onAnalytical Reagents of the American Chemical Society, wheresuch specif
7、ications are available.3Other grades may be used,provided it is first ascertained that the reagent is of sufficientlyhigh purity to permit its use without decreasing the accuracy ofthe determination.TEST METHOD ATOTAL EXTRACTABLES4. Summary of Test Method4.1 Thin, narrow strips of the dried rubber a
8、re extractedthree times with 100 cm3of hot solvent for 10, 20, and 40-minperiods, respectively. The extracted rubber is then extracted for5 min in 100 cm3of hot acetone to thoroughly remove theextraction solvent and aid drying of the rubber. The extractedrubber is then dried to constant mass. The di
9、fference in massbetween the original sample and the extracted sample is thetotal extractables.5. Significance and Use5.1 This procedure is intended to determine the total ex-tractable materials in rubber. It will give the combined amountof rosin and fatty acids, soaps, extender oils, defoamer tars,a
10、ntioxidants, and other uncombined organic constituents thatare extractable in the solvent used. The rubber hydrocarbon canbe estimated by subtracting the sum of the total extract, thetotal ash, the volatile matter, and carbon black content (forcarbon black masterbatch) from 100.6. Apparatus6.1 Wide-
11、Mouth Flask, 400 to 500 cm3.6.2 Hot Plate and Reflux Condenser.NOTE 2Extraction apparatus in Fig. 1 of Test Methods D297 may beused, but without the extraction siphon cup.6.3 Filter Paper and Wire Gauze.6.4 Weighing Dish or Watch Glass.1These test methods are under the jurisdiction of ASTM Committee
12、 D11 onRubber and are the direct responsibility of Subcommittee D11.11 on ChemicalAnalysis.Current edition approved Aug. 1, 2014. Published November 2014. Originallyapproved in 1995. Last previous edition approved in 2009 as D5774 95 (2009).DOI: 10.1520/D5774-95R14.2For referenced ASTM standards, vi
13、sit 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.3Reagent Chemicals, American Chemical Society Specifications, AmericanChemical Society, Washing
14、ton, DC. For Suggestions on the testing of reagents notlisted by the American Chemical Society, see Annual Standards for LaboratoryChemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeiaand National Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville,MD.Copyright AS
15、TM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States16.5 Vacuum Oven, capable of maintaining a temperature of105C and a pressure of 3.0 kPa (23 mm Hg) or less.7. Reagents7.1 Solvents:7.1.1 ETA (Ethanol-Toluene-Azeotrope)Prepare by mix-ing 70 volumes o
16、f ethyl alcohol and 30 volumes of toluene,refluxing the mixture for 4 h over calcium oxide and distilling.Discard the first and last portions, keeping only that distillatecoming over within a range of 1C. Distilling may be omittedif absolute grain alcohol or anhydrous formula 3A alcohol isused.7.1.2
17、 H-ITM (Hydrous Isopropanol-Toluene Mixture)Prepare by mixing 75 volumes of anhydrous isopropanol with25 volumes of toluene and then mixing 92 volumes of thissolution with 8 volumes of water.7.1.3 Acetone.8. Preparation of Sample8.1 Dry the sample in accordance with the proceduredescribed in 8.1.1 o
18、r 8.1.2.8.1.1 Weigh a piece of rubber (at least 450 g) to the nearest0.1 g. Pass the rubber repeatedly through a laboratory mill,with the rolls of the mill maintained at 100 6 5C (212 6 9F)and the distance between the rolls at 0.25 6 0.05 mm (0.010 60.002 in.), as determined by a lead slug. Do not a
19、llow therubber to band, and take care to prevent any loss of sample. Atthe end of 4 min, weigh the rubber to the nearest 0.1 g. Pass therubber through the mill for an additional 2 min, and reweigh it.If the weights at the end of the 4 and 6-min periods are within0.1 g, calculate the volatile matter;
20、 if not, continue passing thesample through the mill for 2-min periods until the weightremains constant within 0.1 g.8.1.2 Sheet out the rubber (at least 250 g) on a laboratorymill, with the distance between the rolls set at 0.25 6 0.05 mm(0.010 6 0.002 in.), as determined by a lead slug, and thetem
21、perature of the roll being no greater than 32C (90F).Weigh the entire sheet to the nearest 0.1 g. Place in aforced-circulation oven set at 100 6 5C (212 6 9F) so thatboth surfaces of the sheet are exposed to the draft. Allow therubber to remain in the oven until the mass is constant to within0.1 g.
22、Usually1hissufficient for rubbers containing no morethan 1.0 % moisture.8.2 Sheet the dry polymer to a thickness of 0.5 mm (0.020in.) or less. Cut approximately6gofthedried, sheeted sampleinto strips not wider than 10 mm or longer than 50 mm.NOTE 3To ensure complete extraction of the rubber, the thi
23、ckness ofthe sheet must not exceed the prescribed maximum.For rubber types that during extraction tend to mass or stick together(that is, low viscosity rubber and alum-coagulated rubber) and for rubbertypes containing materials that are otherwise difficult or slow to extract,the dried sheet may be p
24、repared for extraction by one of the followingmethods to expedite and provide complete extraction:(a) Using a laboratory press with flat heated platens, press 1.5 to 1.7g of the rubber into a tared 89 to 94-mm (3.5 to 3.7-in.) diameter circle ofeither stainless steel screen having openings of approx
25、imately 0.177 mm(80 mesh, 5.2 mil wire diameter) or of polyester monofilament screencloth4that has been previously extracted with the solvent being used.Remove any excess rubber that extends beyond the edge of the screen.Accurately weigh the prepared rubber and screen. After the test iscompleted, th
26、e rubber can be burned off within a muffle furnace and thestainless steel screen can be reused.(b)Cut5to6gofthesheet into squares approximately 38 by 38 mm(1.5 by 1.5 in.) and weigh between two 50-mm (2-in.) squares ofpolypropylene screen5that previously has been extracted in the solventbeing used.9
27、. Procedure9.1 Accurately weigh6gofthedried rubber strips.9.2 Add 100 cm3of the chosen solvent (ETA or H-ITM) tothe extraction flask, and add each strip of the weighed polymerseparately to the flask, swirling the flask after each addition sothat each strip is thoroughly wetted with solvent to avoids
28、ticking. To prevent the sample from sticking to the flask, afilter paper may be placed in the bottom of the flask and a wiregauze may be placed on the hot plate under the flask. Samplepreparation, as described in Note 3(a)or(b) also may be used,if only the total extractables are to be determined.9.3
29、 Reflux the contents of the flask on the hot plate for atleast 10 min (1 h max). Decant the solvent, rinse the rubberwith 20 cm3of fresh solvent, and add 100 cm3of fresh solventto the flask.9.4 Reflux the contents of the flask on the hot plate for atleast 20 min (1 h max). Again decant the solvent,
30、rinse therubber with 20 cm3of fresh solvent, and add 100 cm3of freshsolvent to the flask.9.5 Reflux the contents of the flask on the hot plate for atleast 40 min (1 h max). Again decant the solvent, and then add100 cm3of acetone to the flask.9.6 Reflux again for 5 min to remove the extraction solven
31、tfrom the rubber. Decant and discard the acetone solution.9.7 Transfer the extracted rubber to a tared weighing dish.Place the dish in a vacuum oven and dry for1hat1056 3Cand a pressure not greater than 3.0 kPa (23 mm Hg). Reweighthe dried rubber.10. Calculation10.1 Calculate the percentage of total
32、 extractables as fol-lows:Total extract, % 5 100A 2 B!#/A (1)4The sole source of supply of the polyester monofilament screen cloth known tothe committee at this time is Custom Filter Supply, 8581 Mosley, Houston, TX,77075, style PES212HC, 74/120 mesh. If you are aware of alternative suppliers,please
33、 provide this information to ASTM International Headquarters. Your com-ments will receive careful consideration at a meeting of the responsible technicalcommittee,1which you may attend.5The sole source of supply of the screen known to the committee at this time isa screen with 0.84 mm square opening
34、s and 0.25 mm diameter wire available fromSouthern Press and Media Co., P.O. Box 24, Augusta, GA 30903-0024 under thedesignation of 24 by 24 mesh,130 in. square openings, 10 mil diameter greenpolypropylene screen. If you are aware of alternative suppliers, please provide thisinformation to ASTM Inte
35、rnational Headquarters. Your comments will receivecareful consideration at a meeting of the responsible technical committee,1whichyou may attend.D5774 95 (2014)2where:A = mass of the original dry sample, g, andB = mass of the extracted dried sample, g.11. Precision and Bias611.1 The precision result
36、s for these test methods wereoriginally derived from an interlaboratory test program (ITP)conducted prior to the adoption of Practice D4483 as thereference precision standard for Committee D11 test methodsand therefore was not conducted according to the guidelines setforth in Practice D4483. However
37、, the results of that ITP havebeen translated into Practice D4483 precision expressionformat and are given in this section. See Practice D4483 forterminology and other statistical calculation details.11.2 The precision results in this precision and bias sectiongive an estimate of the precision of th
38、e test method with thematerials used in the particular ITP as described in 11.3. Theprecision parameters should not be used for acceptance orrejection testing of any group of materials without documen-tation that they are applicable to those materials and thespecific testing protocols of the test me
39、thod.11.3 The Type 1 precision is based on a program thatemployed three materials (rubbers), with tests on each of twodays by eight laboratories. A test result is the average of twodeterminations. The precision data are given in Table 1.11.4 Bias is the difference between an average test value andth
40、e reference (true) test property value. Reference values donot exist for this test method; therefore, bias cannot beevaluated.TEST METHOD BORGANIC ACID12. Summary of Test Method12.1 Thin narrow strips of the dried rubber prepared asdescribed in 8.1 and 8.2 are accurately weighed to secure about6 g.
41、The polymer strips are extracted twice in hot extractionsolvent. The solvent extracts and rinsings are combined in a250-cm3volumetric flask and made up to volume with freshsolvent. A 100-cm3portion of the extract solution is titrated tothe first color change with 0.1 M NaOH solution, using thechosen
42、 indicator. The titration and sample mass are used tocalculate the organic acid.13. Significance and Use13.1 This procedure is intended to determine the organicacid remaining in a synthetic rubber. There are two testmethods: B for alum-coagulated polymers, andAfor all others.While these procedures w
43、ere developed for emulsion SBR,they may be applicable to other emulsion polymers. Organicacid in the polymer may affect cure rate of compounded stock.14. Apparatus14.1 Typical Laboratory Apparatus.15. Reagents15.1 Solvents:15.1.1 Ethanol Toluene-Azeotrope (ETA)See 7.1.1. Notapplicable when testing a
44、lum-coagulated polymers.15.1.2 Alternative Extraction SolventHydrousIsopropanol-Toluene Mixture (H-ITM)See 7.1.2. H-ITM isapplicable to all polymers, and especially the alum-coagulatedpolymers.15.2 Indicator Solutions:15.2.1 Meta-Cresol Purple Indicator Solution (0.1 %), inethyl alcohol or in water.
45、 Neutralize each 0.1 g of indicator inthe solution with 26.2 cm3of 0.01 M NaOH solution beforediluting to volume. Store the indicator solution in a brownbottle out of contact with fluorescent lights, which will causethe solution to deteriorate.15.2.2 Thymol Blue Indicator Solution (0.2 %)Dissolve0.0
46、6 g of indicator in 6.45 cm3of 0.02 M aqueous NaOH anddilute to 50 cm3with distilled water. (Recommended for usewith H-ITM extracts.)15.3 Sodium Hydroxide Standard Solution (0.1 M)Prepare and standardize a 0.10 M solution of sodium hydroxide(NaOH).16. Preparation of Sample16.1 Prepare a sample in ac
47、cordance with 8.1 and 8.2.17. Procedures17.1 Procedure ANon-Alum-Coagulated Polymers:17.1.1 Weigh a 6-g specimen of the dried rubber strips to thenearest 1 mg.17.1.2 Add 100 cm3of the chosen solvent (15.1) to theextraction flask and add each strip of the weighed specimenseparately to the flask. Swir
48、l the flask after each addition sothat each strip is thoroughly wetted with solvent to avoidsticking. To prevent the sample from sticking to the flask, afilter paper may be placed in the bottom of the flask, and a wiregauze may be placed on the hot plate under the flask. Samplepreparation, as descri
49、bed in Note 4(b), also may be used.17.1.3 Reflux the contents of the flask on the hot plate for atleast 10 min (1 h, max). Decant the solvent into a 250-cm3volumetric flask, rinse the sample with 20 cm3of fresh solvent,adding the rinsing to the flask. Add 100 cm3of fresh solvent tothe extraction flask.17.1.4 Reflux the contents of the flask on the hot plate for atleast 20 min (1 h, max). Again decant the solvent into thevolumetric flask and rinse the sample with 20 cm3of fresh6Supporting data have been filed at ASTM International Headquarters and may
