1、Designation: D 3900 05aStandard 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 D 3900; the number immediately following the de
2、signation 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 (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 These test methods cover th
3、e 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 additives orpoly
4、merized 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 70mass % ethyl
5、ene9-14Test 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 and EPDM polym
6、ers 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 asstandard. No other un
7、its 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 applica-bility of reg
8、ulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D 297 Test Methods for Rubber ProductsChemicalAnalysisD 3568 Test Methods for RubberEvaluation of EPDM(Ethylene Propylene Diene Terpolymers) Including Mix-tures With OilD 4483 Practice for Evaluating Precision for Test Metho
9、dStandards in the Rubber and Carbon Black ManufacturingIndustriesE 168 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 percent ethylene
10、 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 films are measur
11、ed 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 7.25/6.85 m(1379/14
12、60 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 D 3568.1These test methods are under the jurisdiction of A
13、STM Committee D11 onRubber and are the direct responsibility of Subcommittee D11.11 on ChemicalAnalysis.Current edition approved Dec. 1, 2005. Published January 2006. Originallyapproved in 1980. Last previous edition approved in 2005 as D 390005.2For referenced ASTM standards, visit the ASTM website
14、, 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 Conshohocken, PA 19428-2959, United States.
15、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 should not be used as the sole measure-ment
16、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 have interferences due toadditives and s
17、tabilizers 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 and must be removed before infrared analy
18、sis.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 to667-cm1or 400 000 to 66 700-m1) region
19、 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 operated by an experienced analyst accor
20、ding tothe manufacturers directions for optimum performance. Rec-ommended practices for general techniques of infrared quan-titative analysis are given in Practices E 168.6.3 For routine testing, Fourier Transform Infrared (FT-IR)may be used in place of double beam instruments provided thebaseline c
21、alculation 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) may have different math-ematical form
22、s 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 cutsurface to avoid testing of a partial
23、ly oxidized polymer.8. Precision and Bias38.1 This precision and bias section has been prepared inaccordance with Practice D 4483. Refer to Practice D 4483 forterminology and other statistical calculation details.8.2 The precision results in this precision and bias sectiongive an estimate of the pre
24、cision 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 applicable tothose particular mater
25、ials 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 test methods was determinedfrom an in
26、terlaboratory 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 is a single determination of percen
27、t 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 Test Method C3Supporting data have bee
28、n filed at ASTM International Headquarters and maybe obtained by requesting Research Report RR: D111021.TABLE 1 Type 1 PrecisionNOTEThe midpoint of the range was used to calculate (r) and (R).Test MethodEthyleneRange, %Within LaboratoriesABetween LaboratoriesASrr (r) SRR (R)A 40 to 60 0.569 1.61 3.2
29、2 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, in measurement units.(r) = repeatabi
30、lity, (relative) percent.SR= reproducibility, standard deviation, in measurement units.R = reproducibility, in measurement units.(R) = reproducibility, (relative) percent.D 3900 05a2within one laboratory suggests precision levels similar to the other testmethods.8.6 The precision of these test metho
31、ds 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 meanlevel under consideration at any given
32、 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, that differ by more than this tabulated r
33、(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 obtained in twodifferent laboratories, und
34、er 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) and (R), have equivalent applicationstate
35、ments 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 EPM standard polymers by the five U.S.EPM/E
36、PDM 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 plant polymers or equivalent,with confirmin
37、g 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 78.67 44.88 52.69 69.510 77.58.10.3 The st
38、andards 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 nine laboratories on two days. The results of
39、the 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. Scope9.1 This test method covers the determ
40、ination 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 in some commercial polymers will cause anadd
41、itional 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 unless the oil is first removed by extracti
42、on.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 EPMpolymers is used to prepare a calibration of
43、 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 Analytical Reagents of the American Chemic
44、al Society,4Gardner, I. J., Cozewith, C., Ver Strate, G., “Infrared Determination ofComposition of Ethylene-Propylene Copolymers,” Rubber Chemistry and Technol-ogy, Vol 44, September 1971, pp. 10151024.5Supporting data have been filed at ASTM International Headquarters and maybe obtained by requesti
45、ng Research Report RR: D111065.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 0.550 0.947 0.766 2.15 3.70EPDM306 67.9 0.40
46、0 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.D 3900 05a3where such specifications are available.6Other grades may beused, provided it is first ascertained that the reagent is ofsufficiently high purity to permit its use without lessening theaccuracy of
47、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 200 by 1.5 mm (8 by 8 by0.06 in.).11.6 Polyester F
48、ilm, 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 polyester filmor TFE-fluorocarbon-coated stainless s
49、teel 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 especially sticky orweak films. Mount the film in the sample
