1、Designation: D3137 81 (Reapproved 2018)Standard Test Method forRubber PropertyHydrolytic Stability1This standard is issued under the fixed designation D3137; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision
2、. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the U.S. Department of Defense.1. Scope1.1 This test method covers the determination of
3、the abilityof rubber to withstand the environmental effects of highhumidity. This is accomplished by examination of the materialafter removal from the moisture-laden environment. It isdesigned for testing specimens of rubber materials cut fromstandard sheets prepared in accordance with Practice D318
4、2.1.2 The values stated in SI units are to be regarded as thestandard. The values given in parentheses are for informationonly.1.3 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 a
5、ppro-priate safety, health, and environmental practices and deter-mine the applicability of regulatory limitations prior to use.(For specific precautionary statements, see Note 1.)1.4 This international standard was developed in accor-dance with internationally recognized principles on standard-izat
6、ion established in the Decision on Principles for theDevelopment of International Standards, Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2D412 Test Methods for Vulcanized Rubber and Thermoplas
7、-tic ElastomersTensionD573 Test Method for RubberDeterioration in an AirOvenD3040 Practice for Preparing Precision Statements for Stan-dards Related to Rubber and Rubber Testing (Withdrawn1987)3D3182 Practice for RubberMaterials, Equipment, and Pro-cedures for Mixing Standard Compounds and Preparing
8、Standard Vulcanized Sheets3. Summary of Test Method3.1 Test specimens are exposed to the influence of humidenvironments under definite conditions of temperature,humidity, and time for the purpose of measuring the resultinghydrolytic degradation by noting the change in tensile strengthafter exposure
9、over distilled water.4. Significance and Use4.1 Rubber and rubber products for certain applicationsmust withstand the environmental effect of high humidity andresist the deterioration of physical properties under theseconditions with time. This test method allows performanceproperties to be determin
10、ed under the accelerated conditions ofhigh humidity and elevated temperature.4.2 In view of climatic variations in service conditions, thismethod may not give results correlating exactly with serviceperformance. However, the test method yields comparativedata on which to base judgment as to service
11、quality and it isuseful in research and development work.4.3 This test method is not applicable to coated fabrics; itsuse for materials other than rubber has not been established.5. Test Conditions5.1 TemperatureThe test temperature shall be 85 6 1C(185 6 2F).5.2 Exposure PeriodThe exposure period s
12、hall be 96 6 1h.5.3 Conditioning PeriodAfter the specified exposureperiod, the specimens shall be conditioned on a flat surface for16 to 96 h at 50 6 5 % relative humidity and 23 6 2C (73.46 3.6F).1This test method is under the jurisdiction of ASTM Committee D11 on Rubberand Rubber-like Materials an
13、d is the direct responsibility of Subcommittee D11.15on Degradation Tests.Current edition approved Aug. 1, 2018. Published September 2018. Originallyapproved in 1972. Last previous edition approved in 2013 as D3137 81 (2013).DOI: 10.1520/D3137-81R18.2For referenced ASTM standards, visit the ASTM web
14、site, 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.3The last approved version of this historical standard is referenced onwww.astm.org.Copyright ASTM Internationa
15、l, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards, Guides
16、and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.16. Procedure6.1 Original Tensile StrengthCut three ASTM dumbbellor ring specimens and condition for at least3hat236 2C(73.4 6 3.6F) prior to testing. Determine the original tensilestrength in acco
17、rdance with Test Methods D412.6.2 Deteriorated Tensile StrengthCut three specimensfrom the same rubber sheet from which specimens were cut forthe original tensile strength. Measure the thickness of eachspecimen and suspend the specimens in a container approxi-mately 1 dm3(1 qt) in volume and at leas
18、t 170 mm (6.7 in.) inheight, containing 100 cm3of distilled water. Suspend thespecimens on noncorrosive metal hooks, soldered to thebottom of the container cap or on a glass “tree” placed in thecontainer, so that the specimens do not contact the container oreach other. Cap the container loosely and
19、place the container ina circulating air oven (see Test Method D573) according to therequired test conditions (see 5.1 and 5.2). After 15 min, openthe oven briefly and secure the container cap tightly. At the endof the required exposure period, remove the container from theoven and loosen the cap (se
20、e Note 1). When the container hascooled to approximately room temperature, remove and con-dition the specimens (see 5.3). After the conditioning period,determine the tensile strength in accordance with Test MethodsD412, using the original unexposed thickness or cross-sectional area.NOTE 1The cap of
21、the container should not be secured tightly prior toplacing the container in a circulating air oven at elevated temperature.Such a procedure could result in a potentially hazardous conditioninvolving a pressurized container. Similarly, the container cap should beloosened upon removal from the oven t
22、o prevent the occurrence of apartial vacuum in the sealed container.NOTE 2It should be recognized that the change in tensile strength ofa rubber that has been exposed to the conditions of this test may be due,in part, or totally, to the effects of the elevated temperature rather than tothe effects o
23、f humidity. To aid in distinguishing between the two effects,it is recommended that in addition to testing specimens of rubber bymeans of this method, specimens also be tested for change in tensilestrength in accordance with Test Method D573 for 96 6 1hat856 1C(185 6 2F).NOTE 3In the event that a si
24、gnificant loss in tensile strength is notedafter the 96 6 1-h exposure over water (a loss not attributed to the effectsof heat alone), the rubber may be considered to be hydrolytically unstableunder these conditions. In cases where it is difficult to make this judgment,or whether it is desired to pe
25、rform in-depth studies of the rates ofhydrolysis, the test over water at 85 6 1C (185 6 2F) may be performedfor longer exposure periods. Suggested exposure intervals are 168 6 1,240 6 1, and 336 6 1 h. For in-depth studies of materials having poorresistance to hydrolysis under the standard test cond
26、itions (see Section 5),a lower test temperature such as 70 6 1C (158 6 2F) may be used.6.3 Take the median of the values for three specimens as thecharacteristic of the piece of rubber tested with the exception ofthe following conditions, in which case use the median of thevalues for five specimens:
27、6.3.1 If one or more values do not meet the specifiedrequirements when tested for compliance with specifications,or6.3.2 If referee tests are being made.7. Calculation7.1 Calculate the percentage change in tensile strength asfollows:Percent change in tensile strength 5 T 2 T0! /T0# 3100 (1)where:T0=
28、 original tensile strength of specimens, andT = tensile strength after exposure.8. Report8.1 The report shall include the following:8.1.1 Results calculated in accordance with Section 6,8.1.2 All observed and recorded data on which the calcula-tions are based,8.1.3 Time of exposure,8.1.4 Date of pre
29、paration of the rubber, if known,8.1.5 Date of test, and8.1.6 Type and dimensions of specimens used.9. Precision and Bias9.1 This precision statement was prepared in accordancewith statistical and other testing terminology and conceptspresented in Practice D3040.9.2 The precision of this test method
30、 was calculated fromthe precision statement of Test Methods D412 for the tensilestrength measurement of rubber-like materials. These precisiondata are based on tests conducted exclusively with vulcanizedsheets prepared by the National Bureau of Standards by 69laboratories on 9 materials. A “test res
31、ult” is the mean valueobtained from the testing of 3 dumbbell specimens.9.3 This test method measures the percentage of change intensile strength of a rubber-like material after exposure for 96h to a hydrolytic environment. The best estimate of precisionfor this test method is derived from twice tha
32、t of the variancemeasured for the tensile strength in accordance with TestMethods D412.9.4 The calculated laboratory quality control (LQC) preci-sions for this test method are shown as follows:Property, % change intensile strength Units, %Range of Value,0to100%Within Laboratory Among LaboratoryS CV
33、LSD S CV LSD2.1 0.042 5.9 4.2 0.084 11.99.5 The LQC precision values for S (%) given are equiva-lent to “repeatability” for within-laboratory testing and to“reproducibility” for among-laboratory testing.D3137 81 (2018)2ASTM International takes no position respecting the validity of any patent rights
34、 asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity 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 ti
35、me by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will
36、receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have 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
37、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). Permission rights to photocopy the standard may also be secured from the Copyright Clearance Center, 222Rosewood Drive, Danvers, MA 01923, Tel: (978) 646-2600; http:/ 81 (2018)3
