1、Designation: D3900 05a (Reapproved 2010)Standard Test Methods forRubberDetermination of Ethylene Units in Ethylene-Propylene Copolymers (EPM) and in Ethylene-Propylene-Diene Terpolymers (EPDM) by Infrared Spectrometry1This standard is issued under the fixed designation D3900; the number immediately
2、following the designation indicates 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 These test m
3、ethods cover the determination of theproportion of ethylene and propylene units in ethylene-propylene copolymers (EPM) and ethylene-propylenedieneterpolymers (EPDM) over the range from 35 to 85 mass %ethylene. Four test methods are needed to encompass thevariety of commercial polymers that contain a
4、dditives orpolymerized diene units that interfere with the various infraredpeaks. Except when interferences are present, all four testmethods should give similar results.The test methods appear inthe following order:1.1.1 Pressed Film Test Methods:SectionsTest Method AFor EPM and EPDM between 35 and
5、 70mass % ethylene9-14Test Method BFor EPM and EPDM between 60 and 85mass % ethylene, except for ethylene/propylene/1,4-hexadiene terpolymers15-19Test Method CFor all EPM and EPDM polymers between 35and 85 mass % ethylene, using near infrared20-241.1.2 Cast Film Test Methods:Test Method DFor all EPM
6、 and EPDM polymers between 35and 85 mass % ethylene, except for ethylene/propylene/1,4-hexadiene terpolymers25-321.2 These test methods are not applicable to oil-extendedEPDM unless the oil is first removed in accordance with TestMethod D.1.3 The values stated in SI units are to be regarded asstanda
7、rd. No other units of measurement are included in thisstandard.1.4 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 determine the applic
8、a-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D297 Test Methods for Rubber ProductsChemicalAnaly-sisD3568 Test Methods for RubberEvaluation of EPDM(Ethylene Propylene Diene Terpolymers) Including Mix-tures With OilD4483 Practice for Evaluating Precision f
9、or Test MethodStandards in the Rubber and Carbon Black ManufacturingIndustriesE168 Practices for General Techniques of Infrared Quanti-tative Analysis3. Summary of Test Methods3.1 Test Method APressed films are measured for theirinfrared absorbance ratios at 8.65/13.85 m (1156/722 cm1),and mass perc
10、ent ethylene is read from a calibration obtainedfrom standard polymers.3.2 Test Method BThin pressed films are measured fortheir infrared absorbance ratios at 7.25/13.85 m (1379/722cm1), and mass percent ethylene is read from a calibrationobtained from standard polymers.3.3 Test Method CPressed film
11、s are measured for theirinfrared absorbance ratios at 8.65/2.35 m (1156/4255 cm1)using near infrared, and mass percent ethylene is read from acalibration obtained from standard polymers.3.4 Test Method DUltra-thin cast films on a salt plate aremeasured for their infrared absorbance ratios at 7.25/6.
12、85 m(1379/1460 cm1), and mass percent ethylene is read from acalibration obtained from standard polymers.4. Significance and Use4.1 These test methods can be used for determining whichEPDM polymers are evaluated in the different compounds inTest Methods D3568.1These test methods are under the jurisd
13、iction of ASTM Committee D11 onRubber and are the direct responsibility of Subcommittee D11.11 on ChemicalAnalysis.Current edition approved June 1, 2010. Published December 2010. Originallyapproved in 1980. Last previous edition approved in 2005 as D3900 05a. DOI:10.1520/D3900-05AR10.2For referenced
14、 ASTM standards, visit 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.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Cons
15、hohocken, PA 19428-2959, United States.4.2 Differences in ethylene sequence distribution causedifferences in crystallinity and green strength at the sameethylene content. Since these are important variables in EPMand EPDM processability and end-use properties, the ethylenecontent of the rubber shoul
16、d not be used as the sole measure-ment to determine the suitability of a particular rubber for anintended purpose.5. Interferences5.1 Ethylene/propylene/1,4-hexadiene EPDM has an inter-ference at the 7.25-m (1379-cm1) peak and should bemeasured by Test Method A or C.5.2 Various commercial polymers h
17、ave interferences due toadditives and stabilizers that prevent or hinder the use of the8.65-m (1156-cm1) peak. Test Methods A and C should beapplied carefully, or Test Methods B and D should be used asdescribed in the procedure.5.3 Extender oil, when present, will interfere with alldeterminations an
18、d must be removed before infrared analysis.6. Apparatus6.1 Hydraulic Press, capable of 200 MPa (29 000 psi) and150C.6.2 Infrared Spectrophotometer, double-beam, having a per-cent transmission specification of 61 %, or better, at full scale,capable of recording a spectrum over the 2.5 to 15-m (4000 t
19、o667-cm1or 400 000 to 66 700-m1) region for Test MethodsA, B, and D. Test Method C requires an instrument capable ofrecording a spectrum over the 2.0 to 15-m (2000 to 667-cm1or 200 000 to 66 700-m1) region. Any spectrophotometercomplying with these requirements may be used. The equip-ment shall be o
20、perated by an experienced analyst according tothe manufacturers directions for optimum performance. Rec-ommended practices for general techniques of infrared quan-titative analysis are given in Practices E168.6.3 For routine testing, Fourier Transform Infrared (FT-IR)may be used in place of double b
21、eam instruments provided thebaseline calculation procedures in the Procedures and Calcu-lation Sections of each method are followed. Sample filmtemperature is lower with FT-IR than double beam instruments,and some partly crystalline polymers may respond differently.Calibration equations (Section 33)
22、 may have different math-ematical forms with FT-IR.7. Sampling7.1 Take precautions to ensure as representative a sample aspossible for spectral analysis, since infrared absorption isadditive in nature and will be influenced by extraneousmaterials.7.2 Where possible, take the sample from a freshly cu
23、tsurface to avoid testing of a partially oxidized polymer.8. Precision and Bias38.1 This precision and bias section has been prepared inaccordance with Practice D4483. Refer to Practice D4483 forterminology and other statistical calculation details.8.2 The precision results in this precision and bia
24、s sectiongive an estimate of the precision of these test methods with thematerials (rubbers) used in the particular interlaboratory pro-gram as described below. The precision parameters should notbe used for acceptance or rejection testing of any group ofmaterials without documentation that they are
25、 applicable tothose particular materials and the specific testing protocols thatinclude these test methods.8.3 A Type 1 (interlaboratory) precision was evaluated.Both repeatability and reproducibility are short term; a periodof a few days separates replicate test results.8.4 The precision of these t
26、est methods was determinedfrom an interlaboratory study of several materials by severallaboratories on two days as explained below:Test MethodEthyleneRange, %No. ofLaboratoriesNo. ofMaterialsA 4060 6 3A 6576 5 2B 6066 4 2D (NonoilExtended Polymer) 4070 4 4D (Oil-Extended Polymer) 72 3 1A test result
27、 is a single determination of percent ethylene.8.5 The results of the precision calculations for repeatabilityand reproducibility are given in Table 1 for Test MethodsA, B,and D.NOTE 1Insufficient data were generated for Test Method C to calcu-late a precision statement. However, extensive use of Te
28、st Method C3Supporting data have been filed at ASTM International Headquarters and maybe obtained by requesting Research Report RR: D11-1021.TABLE 1 Type 1 PrecisionNOTEThe midpoint of the range was used to calculate (r) and (R).Test MethodEthyleneRange, %Within LaboratoriesABetween LaboratoriesASrr
29、 (r) SRR (R)A 40 to 60 0.569 1.61 3.22 0.857 2.43 4.86A 65 to 76 0.471 1.33 1.90 1.74 4.92 7.0B 60 to 66 0.433 1.23 1.95 0.540 1.53 2.43D(Non OE) 40 to 70 0.856 2.42 4.40 2.11 5.97 10.9D72 2.12 6.00 8.3 3.55 10.0 13.9(OE)ASr= repeatability, standard deviation, in measurement units.r = repeatability,
30、 in measurement units.(r) = repeatability, (relative) percent.SR= reproducibility, standard deviation, in measurement units.R = reproducibility, in measurement units.(R) = reproducibility, (relative) percent.D3900 05a (2010)2within one laboratory suggests precision levels similar to the other testme
31、thods.8.6 The precision of these test methods may be expressed inthe format of the following statements, which use an appro-priate value of r, R,(r), or (R), to be used in decisions abouttest results. The appropriate value is that value of r or Rassociated with a mean level in Table 1 closest to the
32、 meanlevel under consideration at any given time, for any givenmaterial, in routine testing operations.8.7 RepeatabilityThe repeatability, r, of these test meth-ods has been established as the appropriate value tabulated inTable 1. Two single test results, obtained under normal testmethod procedures
33、, that differ by more than this tabulated r(for any given level) must be considered as derived fromdifferent or nonidentical sample populations.8.8 ReproducibilityThe reproducibility, R, of these testmethods has been established as the appropriate value tabu-lated in Table 1. Two single test results
34、 obtained in twodifferent laboratories, under normal test method procedures,that differ by more than the tabulated R (for any given level)must be considered to have come from different or nonidenticalsample populations.8.9 Repeatability and reproducibility expressed as a percentof the mean level, (r
35、) and (R), have equivalent applicationstatements as above for r and R. For the (r) and (R) statements,the difference in the two single test results is expressed as apercent of the arithmetic mean of the two test results.8.10 Bias:8.10.1 Bias was established with a round-robin test con-ducted on six
36、EPM standard polymers by the five U.S.EPM/EPDM manufacturers. Each manufacturer made eightdeterminations on each of the six standards, using his owninfrared method and absorbance/ethylene calibration chart.Each individual calibration chart had been established withinfrared tests of C14-tagged pilot
37、plant polymers or equivalent,with confirming tests such as NMR used where necessary.48.10.2 Ethylene contents of the following ten EPM stan-dards were established via 13C NMR by a consortium ofEuropean and North American laboratories.Standard No. Mass Percent Ethylene51 40.12 52.43 58.64 66.85 70.86
38、 78.67 44.88 52.69 69.510 77.58.10.3 The standards were each produced in a commercialplant and sizable quantities have been set aside for calibrationpurposes (see 13.2).8.11 The precision of Test Method A was determinedutilizing FTIR spectrometers from an interlaboratory study offive materials by ni
39、ne laboratories on two days. The results ofthe precision calculations for repeatability and reproducibilityare given in Table 2. The FTIR spectrometers utilized werecalibrated using the percent ethylene values established by 13CNMR.TEST METHOD APRESSED FILM METHODUSING THE 8.65/13.85-m PEAK RATIO9.
40、Scope9.1 This test method covers the determination of percentethylene in EPM and EPDM between approximately 35 and 70mass %.9.2 This test method may be used with caution betweenapproximately 60 and 80 mass % ethylene, but is inferior toTest Method B in precision with many instruments.9.3 Additives i
41、n some commercial polymers will cause anadditional absorbance on the shoulder of the 8.65-m (1156-cm1) peak at approximately 8.93 m (1120 cm1), givingdifficulty in drawing the baseline. Where this occurs, TestMethod B or D must be used.9.4 This test method is not intended for oil-extended poly-mers
42、unless the oil is first removed by extraction.10. Summary of Test Method10.1 This test method makes use of the ratio of the absor-bance of methyl groups from propylene units at 8.65 m (1156cm1) versus the absorbance of methylene sequences fromethylene units at 13.85 m (722 cm1).Aseries of known EPMp
43、olymers is used to prepare a calibration of A8.65/A13.85versusmass percent ethylene.11. Reagents and Materials11.1 Purity of ReagentsReagent grade chemicals shall beused in all tests. Unless otherwise indicated, it is intended thatall reagents shall conform to the specifications of the Commit-tee on
44、 Analytical Reagents of the American Chemical Society,4Gardner, I. J., Cozewith, C., Ver Strate, G., “Infrared Determination ofComposition of Ethylene-Propylene Copolymers,” Rubber Chemistry and Tech-nology, Vol 44, September 1971, pp. 1015 1024.5Supporting data have been filed at ASTM International
45、 Headquarters and maybe obtained by requesting Research Report RR: D11-1065.TABLE 2 Type 1 Precision Test Method AAMaterialMeanLevel, %Within Laboratories Between LaboratoriesSrr (r) SRR (R)EPDM1237 52.4 0.259 0.724 1.38 0.557 1.56 2.98EPDM865 56.9 0.225 0.629 1.11 0.688 1.93 3.39EPDM2154 58.1 0.197
46、 0.550 0.947 0.766 2.15 3.70EPDM306 67.9 0.400 1.12 1.65 0.814 2.28 3.36EPDM227 74.4 0.711 1.99 2.67 1.12 3.14 4.22Ap =9,q = 5, and m =2.D3900 05a (2010)3where such specifications are available.6Other grades may beused, provided it is first ascertained that the reagent is ofsufficiently high purity
47、to permit its use without lessening theaccuracy of the determination.11.2 Exercise all safety and health precautions while carry-ing out the subsequent analyses, especially those involving theuse of toxic or flammable solvents, or both.11.3 Acetone.11.4 Adhesive Labels.11.5 Flat Steel Plates, 200 by
48、 200 by 1.5 mm (8 by 8 by0.06 in.).11.6 Polyester Film, uncoated, 0.04 mm (0.0015 in.) thick.11.7 TFE-Fluorocarbon-Coated Stainless Steel or Alumi-num Foil.12. Procedure12.1 Cut a small piece of polymer about the size of amatchhead (equivalent to 0.2 g).12.2 Place the polymer between two sheets of p
49、olyester filmor TFE-fluorocarbon-coated stainless steel or aluminum foil.12.3 Insert the sheets of film between the platens of thepress, or if the platens are too rough, between the steel plates,and then between the platens of the press.12.4 Press the sample for 30 to 60 s at 70 MPa (10 000 psi)and 150C.12.5 Release the pressure, remove from the press, cool, andcarefully remove the polymer film from the polyester film orTFE-fluorocarbon-coated foil. Acetone may be used as arelease agent from the polyester film for especiall
