1、Designation: D 3855 84 (Reapproved 2004)Standard Test Method forRubber ThreadDeterioration Due to Standard WashingSolution Treatment1This standard is issued under the fixed designation D 3855; the number immediately following the designation indicates the year oforiginal adoption or, in the case of
2、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 This test method covers the measurement of the relativedeterioration resistance of bare rubber
3、threads subjected to astandard washing solution when they are dried at roomtemperature and heat aged.1.2 The results obtained by this test method are onlycomparative since it may not be possible to absolutely correlatesuch results with actual service life of the threads or of anarticle containing th
4、e threads.1.3 The values stated in SI units are to be regarded as thestandard. The values given in parentheses are for informationonly.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 est
5、ablish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D 2433 Test Methods for Rubber ThreadE 145 Specification for Gravity-Convection and Forced-Ventilation Ovens3. Summary of Test Method3.1
6、The initial properties of the thread are determined by theappropriate test methods in accordance with Test MethodsD 2433. The same test specimens, extended to 100 % elonga-tion, are subjected to one cycle of washing, drying, andair-oven aging.3.2 The physical property measured in the test may be any
7、one of those described in Sections 18 to 37 of Test MethodsD 2433; however, the most suitable are the Schwartz value(Section 25) or stress retention (Section 35).4. Significance and Use4.1 Rubber threads or garments containing rubber threadsare very often subjected to washing treatments that differc
8、onsiderably in the composition and temperature of the wash-ing solution used. Information on the composition of commer-cial detergents used is not readily available, and the same brandname may contain variations in composition.5. Apparatus5.1 Constant-Rate-Of-Extension (CRE) Type Tensile TestingMach
9、ine, with a load capacity from 0.1 to 20 N (10 to 2000 gf),equipped with hooks.5.2 Masonite and a Stainless Steel or Glass Form,ofsuitable dimensions to hold the thread loops elongated to100 %.NOTE 1If the Schwartz value is used, it is advisable to restrict themaximum massaging extension to 300 % to
10、 avoid excessive specimenbreakage during massaging after aging. If the stress retention at 100 %elongation is used, massage the thread to 300 % extension for six cyclesimmediately before extending to the stress to be measured.5.2.1 FormA form, 100 by 300 by 3 mm (4 by 12 by18in.), with the center se
11、ction cut out as illustrated in Fig. 1, andwith the outside edges rounded, is suitable for this purpose.5.3 Constant-Temperature Water Bath.5.4 Thermometer, with a range from 0 to 100C in 0.2Cdivisions.5.5 Circulating Hot-Air Oven, conforming to SpecificationE 145, capable of maintaining a temperatu
12、re of 125 6 2C.5.6 Beakers, 1500-cm3.6. Standard Washing Solution6.1 The standard washing solution shall be prepared asfollows:6.1.1 Dissolve the following ingredients in 1 L of distilledwater:dodecyl benzene sodium sulfonate 1.0 ganhydrous sodium tripolyphosphate 1.5 gsodium perborate 0.5 gsodium s
13、ilicate (Na2O:SiO2= 1:2 anhydrous) 0.5 ganhydrous sodium sulfate 1.0 gcupric sulfate pentahydrate 0.0086 g1This test method is under the jurisdiction of ASTM Committee D11 on Rubberand is the direct responsibility of Subcommittee D11.37 on Coated Fabrics andRubber Thread.Current edition approved Dec
14、 1, 2004. Published December 2004. Originallyapproved in 1979. Last previous edition approved in 2000 as D 3855 84 (2000).2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, re
15、fer 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.6.1.2 Within 1 h prior to the wash test, dissolve 2.0 g ofsodium perborate in 98.0 g of distilled water at room tempera-tur
16、e. Add 25 g of this solution to 975 g of the solutiondescribed in 6.1.1 heated to the wash temperature immediatelybefore immersing the specimens.6.2 Use 100 g of the standard wash solution for each gramof thread under test. When the amount of wash solution neededto cover the samples exceeds this rat
17、io, add to the bath morethread of the same class to make up the deficiency.7. Test Specimens7.1 Prepare three test specimens from each sample ofrelaxed and conditioned rubber thread. Condition the testspecimens in accordance with Section 5 on Sample Preparationof Test Methods D 2433.7.2 Each test pi
18、ece shall consist of five 50-mm (2-in.) loops(10 ends) formed from a single end of thread 500 mm (20 in.)long at the knot.7.3 Equalize the length of each loop by rotating the testspecimen around the first finger of each hand.8. Preparation of Apparatus8.1 Adjust the tension testing machine as follow
19、s:8.1.1 Gage length to 50 mm (2 in.).8.1.2 Cross-head speed 0.5 m (20 in.)/min.8.1.3 Chart speed 0.5 m (20 in.)/min.8.1.4 Calibrate the instrument with the proper load cell andhooks installed.8.1.5 Set the full-scale load on the tester so that theestimated load on the test specimen at 300 % elongati
20、on (Note1) falls between 50 and 90 % of full-scale deflection.9. Procedure9.1 Original PropertyDetermine the initial selectedphysical property in accordance with the appropriate section ofTest Methods D 2433, using the recommended number of testspecimens.9.2 Place the loops of one end of a test spec
21、imen onto astationary hook. Grip the loops at the opposite end with ahand-held hook. Gently massage the test specimen by extend-ing for six times to the chosen maximum extension (Note 1)immediately before being extended for the stress to be mea-sured.9.3 On the fourth cycle, stop at 300 % elongation
22、 and holdfor 1 min. Transfer to the hooks of the tension testing machine.Cycle the machine to 300 % elongation and return whilerecording the stress curve on the chart.9.4 Remove the test specimens from the hooks. Extend to100 mm (4 in.) and place on the glass or stainless steel formover a cutout are
23、a. Rotate the test specimen on the form toequalize the tension between loops.9.5 Repeat 9.2 and 9.3 for the remaining test specimens. Ifa test specimen should break or the knot slip, substitute anothertest specimen.9.6 After the last specimen has been placed on the stainlesssteel or glass form, allo
24、w a rest period of 60 6 10 min.9.7 Washing ProcedureImmerse the stainless steel formin the standard wash solution, prepared in accordance withSection 6,at856 2C for 1 h with mild agitation. Keep thestandard wash solution in a 1500-cm3beaker immersed in a hotwater bath controlled to a temperature tha
25、t will maintain thewash solution at 856 2C (185 6 3.6F) for 1 h.9.8 Remove the forms from the solution, rinse the testspecimens on the form for 10 min with running lukewarmwater, blot free of excess water with an absorbent towel, anddry at room temperature for 110 min.9.9 Transfer the test specimens
26、 still at 100 % elongation, toa Masonite form and equalize the tension in the loops byrotating them around the form.9.10 Heat AgingHeat age the test specimens in thecirculating air oven, previously set at 125 6 2C, for 4 h.9.11 Remove the forms from the oven and condition the testspecimens on a Mas
27、onite form for a minimum of 16 h inaccordance with Section 5 on Sample Preparation of TestMethods D 2433.9.12 Final MeasurementMeasure the residual values ofthe selected physical properties by the method used for theinitial value in accordance with 9.2 and 9.3.10. Calculation10.1 Express the perform
28、ance of the thread as the percentretention of the initial value of the selected physical propertycalculated as follows:SRW5L2L13 100 (1)FIG. 1 Stretch FormD 3855 84 (2004)2where:SRW= percent of original value of any property retainedby the test specimen after washing and heat treat-ment,L1= average
29、initial value of the selected physical prop-erty, andL2= average residual value of that property after thewashing and aging treatment.11. Report11.1 Report the following information:11.1.1 Full description of the sample and its origin,11.1.2 Physical property selected, the test apparatus utilizedto
30、perform the specific test, and11.1.3 Percent retention of the initial value for physicalproperty selected.12. Precision and Bias12.1 The precision and bias of this test method have not yetbeen determined. Interlaboratory testing has not been done, aslaboratories to do the work have not been located.
31、13. Keywords13.1 deterioration; rubber thread; standard washing solutionASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of
32、 any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments ar
33、e invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not rec
34、eived 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 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).D 3855 84 (2004)3
