1、Designation: D3900 15D3900 17Standard 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 following t
2、he 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 methods cove
3、r the determination of the proportion of ethylene and propylene units in ethylene-propylenecopolymers (EPM) and ethylene-propylenediene terpolymers (EPDM) over the range from 35 to 85 mass % ethylene. Four testmethods are needed to encompass the variety of commercial polymers that contain additives
4、or polymerized diene units thatinterfere with the various infrared peaks. Except when interferences are present, all four test methods should give similar results.The test methods appear in the following order:1.1.1 Pressed Film Test Methods:SectionsTest Method AFor EPM and EPDM between 35 and 70mas
5、s % 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 and E
6、PDM polymers between 35and 85 mass % ethylene, except for ethylene/propylene/1,4-hexadiene terpolymers25 321.2 These test methods are not applicable to oil-extended EPDM unless the oil is first removed in accordance with Test MethodD.1.3 The values stated in SI units are to be regarded as standard.
7、No other units of measurement are included in this standard.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety safety, health, and healthenvironmental practice
8、s and determine theapplicability of regulatory limitations prior to use.1.5 This international standard was developed in accordance with internationally recognized principles on standardizationestablished in the Decision on Principles for the Development of International Standards, Guides and Recomm
9、endations issuedby the World Trade Organization Technical Barriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2D297 Test Methods for Rubber ProductsChemical AnalysisD3568 Test Methods for RubberEvaluation of EPDM (Ethylene Propylene Diene Terpolymers) Including Mixtures With
10、OilD4483 Practice for Evaluating Precision for Test Method Standards in the Rubber and Carbon Black Manufacturing IndustriesE168 Practices for General Techniques of Infrared Quantitative Analysis1 These test methods are under the jurisdiction of ASTM Committee D11 on Rubber and Rubber-like Materials
11、 and are the direct responsibility of Subcommittee D11.11on Chemical Analysis.Current edition approved June 1, 2015Oct. 1, 2017. Published July 2015October 2017. Originally approved in 1980. Last previous edition approved in 20102015 asD3900 05a (2010).D3900 15. DOI: 10.1520/D3900-15.10.1520/D3900-1
12、7.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.This document is not an ASTM standard and is intended only
13、to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
14、of the standard as published by ASTM is to be considered the official document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States13. Summary of Test Methods3.1 Test Method APressed films are measured for their infrared absorbance ratios
15、at 8.65/13.85 m (1156/722 cm1), and masspercent ethylene is read from a calibration obtained from standard polymers.NOTE 1Peak typically appears at the wavelength indicated, but peak may shift slightly in its position.3.2 Test Method BThin pressed films are measured for their infrared absorbance rat
16、ios at or near 7.25/13.85 m (1379/722cm1), and mass percent ethylene is read from a calibration obtained from standard polymers.3.3 Test Method CPressed films are measured for their infrared absorbance ratios at or near 8.65/2.35 m (1156/4255 cm1)using near infrared, and mass percent ethylene is rea
17、d from a calibration obtained from standard polymers.3.4 Test Method DUltra-thin cast films on a salt plate are measured for their infrared absorbance ratios at or near 7.25/6.85m (1379/1460 cm1), and mass percent ethylene is read from a calibration obtained from standard polymers.4. Significance an
18、d Use4.1 These test methods can be used for determining which EPDM polymers are evaluated in the different compounds in TestMethods D3568.4.2 Differences in ethylene sequence distribution cause differences in crystallinity and green strength at the same ethylenecontent. Since these are important var
19、iables in EPM and EPDM processability and end-use properties, the ethylene content of therubber should not be used as the sole measurement to determine the suitability of a particular rubber for an intended purpose.5. Interferences5.1 Ethylene/propylene/1,4-hexadiene EPDM has an interference at the
20、7.25-m (1379-cm1) peak and should be measured byTest Method A or C.5.2 Various commercial polymers have interferences due to additives and stabilizers that prevent or hinder the use of the8.65-m (1156-cm1) peak. Test Methods A and C should be applied carefully, or Test Methods B and D should be used
21、 asdescribed in the procedure.5.3 Extender oil, when present, will interfere with all determinations and must be removed before infrared analysis.6. Apparatus6.1 Hydraulic Press, capable of 200 MPa (29 000 psi) and 150C.6.2 Infrared Spectrophotometer, double-beam, having a percent transmission speci
22、fication of 61 %, or better, at full scale,capable of recording a spectrum over the 2.5 to 15-m (4000 to 667-cm1 or 400 000 to 66 700-m1) region for Test Methods A,B, and D. Test Method C requires an instrument capable of recording a spectrum over the 2.0 to 15-m (2000 to 667-cm1 or200 000 to 66 700
23、-m1) region. Any spectrophotometer complying with these requirements may be used. The equipment shall beoperated by an experienced analyst according to the manufacturers directions for optimum performance. Recommended practicesfor general techniques of infrared quantitative analysis are given in Pra
24、ctices E168.6.3 For routine testing, Fourier Transform Infrared (FT-IR) may be used in place of double beam instruments provided thebaseline calculation procedures in the Procedures and Calculation Sections of each method are followed. Sample film temperatureis lower with FT-IR than double beam inst
25、ruments, and some partly crystalline polymers may respond differently. Calibrationequations (Section 33) may have different mathematical forms with FT-IR.7. Sampling7.1 Take precautions to ensure as representative a sample as possible for spectral analysis, since infrared absorption is additivein na
26、ture and will be influenced by extraneous materials.7.2 Where possible, take the sample from a freshly cut surface to avoid testing of a partially oxidized polymer.8. Precision and Bias38.1 This precision and bias section has been prepared in accordance with Practice D4483. Refer to Practice D4483 f
27、orterminology and other statistical calculation details.8.2 The precision results in this precision and bias section give an estimate of the precision of these test methods with thematerials (rubbers) used in the particular interlaboratory program as described below. The precision parameters should
28、not be usedfor acceptance or rejection testing of any group of materials without documentation that they are applicable to those particularmaterials and the specific testing protocols that include these test methods.3 Supporting data have been filed at ASTM International Headquarters and may be obta
29、ined by requesting Research Report RR: D11-1021.D3900 1728.3 AType 1 (interlaboratory) precision was evaluated. Both repeatability and reproducibility are short term; a period of a fewdays separates replicate test results.8.4 The precision of these test methods was determined from an interlaboratory
30、 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 percent ethylene.8.
31、5 The results of the precision calculations for repeatability and reproducibility are given in Table 1 for Test Methods A, B,and D.NOTE 2Insufficient data were generated for Test Method C to calculate a precision statement. However, extensive use of Test Method C within onelaboratory suggests precis
32、ion levels similar to the other test methods.8.6 The precision of these test methods may be expressed in the format of the following statements, which use an appropriatevalue of r,R, (r), or (R), to be used in decisions about test results. The appropriate value is that value of r or R associated wit
33、h amean level in Table 1 closest to the mean level under consideration at any given time, for any given material, in routine testingoperations.8.7 RepeatabilityThe repeatability, r, of these test methods has been established as the appropriate value tabulated in Table1. Two single test results, obta
34、ined under normal test method procedures, that differ by more than this tabulated r (for any givenlevel) must be considered as derived from different or nonidentical sample populations.8.8 ReproducibilityThe reproducibility, R, of these test methods has been established as the appropriate value tabu
35、lated inTable 1. Two single test results obtained in two different laboratories, under normal test method procedures, that differ by morethan the tabulated R (for any given level) must be considered to have come from different or nonidentical sample populations.8.9 Repeatability and reproducibility
36、expressed as a percent of the mean level, (r) 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 a percentof the arithmetic mean of the two test results.8.10 Bias:8.10.1 Bias was establish
37、ed with a round-robin test conducted on six EPM standard polymers by the five U.S. EPM/EPDMmanufacturers. Each manufacturer made eight determinations on each of the six standards, using his own infrared method andabsorbance/ethylene calibration chart. Each individual calibration chart had been estab
38、lished with infrared tests of C14-tagged pilotplant polymers or equivalent, with confirming tests such as NMR used where necessary.48.10.2 Ethylene contents of the following ten EPM standards were established via 13C NMR by a consortium of European andNorth American laboratories.4 Gardner, I. J., Co
39、zewith, C., Ver Strate, G., “Infrared Determination of Composition of Ethylene-Propylene Copolymers,” Rubber Chemistry and Technology, Vol 44,September 1971, pp. 1015 1024.TABLE 1 Type 1 PrecisionNOTE 1The midpoint of the range was used to calculate (r) and (R).Test Method EthyleneRange, % Within La
40、boratoriesA Between LaboratoriesASr r (r) SR R (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 10.9D(OE) 72 2.12 6.00 8.3 3.55 10.0 13.9A Sr = repeatability, standard deviation
41、, in measurement units.r = repeatability, in measurement units.(r) = repeatability, (relative) percent.SR = reproducibility, standard deviation, in measurement units.R = reproducibility, in measurement units.(R) = reproducibility, (relative) percent.D3900 173Standard No. Mass Percent Ethylene51 40.1
42、2 52.43 58.64 66.85 70.86 78.67 44.88 52.69 69.510 77.58.10.3 The standards were each produced in a commercial plant and sizable quantities have been set aside for calibrationpurposes (see 13.2).8.11 The precision of Test Method A was determined utilizing FTIR spectrometers from an interlaboratory s
43、tudy of fivematerials by nine laboratories on two days. The results of the precision calculations for repeatability and reproducibility are givenin Table 2. The FTIR spectrometers utilized were calibrated using the percent ethylene values established by 13C NMR.TEST METHOD APRESSED FILM METHOD USING
44、 THE 8.65/13.85-m PEAK RATIO9. Scope9.1 This test method covers the determination of percent ethylene in EPM and EPDM between approximately 35 and 70mass %.9.2 This test method may be used with caution between approximately 60 and 80 mass % ethylene, but is inferior to TestMethod B in precision with
45、 many instruments.9.3 Additives in some commercial polymers will cause an additional absorbance on the shoulder of the 8.65-m (1156-cm1)peak at approximately 8.93 m (1120 cm1), giving difficulty in drawing the baseline. Where this occurs, Test Method B or D mustbe used.9.4 This test method is not in
46、tended for oil-extended polymers unless the oil is first removed by extraction.9. Scope9.1 This test method covers the determination of percent ethylene in EPM and EPDM between approximately 35 and 70mass %.9.2 This test method may be used with caution between approximately 60 and 80 mass % ethylene
47、, but is inferior to TestMethod B in precision with many instruments.9.3 Additives in some commercial polymers will cause an additional absorbance on the shoulder of the 8.65-m (1156-cm1)peak at approximately 8.93 m (1120 cm1), giving difficulty in drawing the baseline. Where this occurs, Test Metho
48、d B or D mustbe used.9.4 This test method is not intended for oil-extended polymers unless the oil is first removed by extraction.10. Summary of Test Method10.1 This test method makes use of the ratio of the absorbance of methyl groups from propylene units at 8.65 m (1156 cm1)versus the absorbance o
49、f methylene sequences from ethylene units at 13.85 m (722 cm1). A series of known EPM polymers isused to prepare a calibration of A8.65 /A13.85 versus mass percent ethylene.5 Supporting data have been filed at ASTM International Headquarters and may be obtained by requesting Research Report RR: D11-1065.TABLE 2 Type 1 Precision Test Method AAMaterial MeanLevel, % Within Laboratories Between LaboratoriesSr r (r) SR R (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 3.39EPD
