1、Designation: D 6284 02Standard Test Method forRubber PropertyEffect of Aqueous Solutions withAvailable Chlorine and Chloramine1This standard is issued under the fixed designation D 6284; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revisi
2、on, 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 procedures for evaluating theability of rubber and rubber-like materials to w
3、ithstand theeffects of aqueous solutions with available chlorine andchloramine. It is intended to compare the effects of chlorinecompounds, present in potable water due to disinfectionprocedures, on rubber articles.1.2 Test solutions are designed to contain chlorine com-pounds, including hypochlorou
4、s acid (HOCI), hypochloriteions (OCI), and monochloramine (NH2Cl).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 appro-priate safety and health practices and determine the app
5、lica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:D 471 Test Method for Rubber PropertyEffect of Liq-uids2D 1193 Specification for Reagent Water3D 1253 Test Methods for Residual Chlorine in Water3D 1889 Test Method for Turbidity of Water3D 2240 Test Method
6、for Rubber PropertyDurometerHardness2D 3182 Practice for RubberMaterials, Equipment, andProcedures for Mixing Standard Compounds and Prepar-ing Standard Vulcanized Sheets2D 3183 Practice for RubberPreparation of Pieces for TestPurposes from Products2D 4483 Practice for Determining Precision for Test
7、 MethodStandards in the Rubber and Carbon Black Industries23. Terminology3.1 The terminology of chlorine compounds used in this testmethod is in accordance with Test Methods D 1253, Section 7.3.2 combined residual chlorineresidual consisting ofchlorine combined with ammonia nitrogen and nitrogenousc
8、ompounds.3.3 free available chlorine residualresidual consisting ofhypochlorite ions (OCI) or hydrochlorous acid (HOCl), orboth.3.4 total residual chlorine (chlorine residual)the amountof available chlorine-induced oxidants present in water at anyspecified period, subsequent to the addition of chlor
9、ine.4. Summary of Test Method4.1 This test method provides procedures for exposing testpieces to aqueous available chlorine and chloramine solutionsunder defined conditions of temperature and time.4.2 This test method includes the following procedures:Change in mass after immersion Section 10Change
10、in volume after immersion Section 11Change in hardness after immersion Section 12Visual and turbidity rating after immersion Section 134.3 The resulting deterioration is measured by changes inmass, volume, hardness, and appearance of the test piecesurfaces and test liquid after immersion.4.4 This te
11、st method also describes the preparation of theimmersion liquids.5. Significance and Use5.1 Rubber articles, such as seals, gaskets, and membranes,may be exposed in service to chlorine compounds used inpotable water as disinfectants. The exposure may be intermit-tent or continuous and can occur at v
12、arious temperatures.5.2 Properties of rubber articles can deteriorate as a result ofexposure to water containing these chlorine compounds, af-fecting their performance for the intended use.5.3 This test method attempts to simulate service conditionsthrough controlled accelerated testing, but may not
13、 give adirect correlation with part performance under actual serviceconditions. It yields comparative data on which to basejudgement on expected service quality.5.4 This test method is suitable for compliance testing,quality control, and research and development work.1This test method is under the j
14、urisdiction of ASTM Committee D11 on Rubberand is the direct responsibility of Subcommittee D11.40 on Consumer RubberProducts.Current edition approved Dec. 10, 2002. Published December 2002. Originallyapproved in 1998. Last previous edition approved in 1998 as D 6284 98.2Annual Book of ASTM Standard
15、s, Vol 09.01.3Annual Book of ASTM Standards, Vol 11.01.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.6. Test Conditions6.1 TemperatureUnless otherwise specified between theproducer and the purchaser, the preferred test temperature
16、shallbe 70 6 2C (158 6 4F).6.1.1 If the temperature of the testing room is other than thestandard 23 6 2C (73 6 4F), the actual room temperatureand any effect on the temperature of the test liquids shall bereported.6.2 Immersion PeriodsUnless otherwise specified, theimmersion periods shall be as ind
17、icated in Table 1, dependingon the anticipated service conditions.6.2.1 To obtain a measure on the rate of deterioration, it isnecessary to take measurements after several immersion peri-ods. The tolerance of the immersion times shall be 615 min or61 % of the specified time, whichever is greater.7.
18、Apparatus7.1 A three-necked flask4with a capacity of 2000 cm3shallbe mounted in an electric heating mantle5of sufficient size andwattage to maintain the specified temperature throughout thetest solution. The center neck of the flask shall be used forinserting and removing test pieces and shall be fi
19、tted with aremovable glass stopper. The other two necks of the flask shallbe tightly fitted with an immersion thermometer and a Grahamcondenser6with continuous cooling water supply.7.2 Test procedures utilizing continuous monitoring of testliquids and automatic addition of reagents may be used but c
20、anbe expected to produce different results than those obtained bythe procedures of this test method.8. Standard Test Liquids8.1 Standard test liquids are prepared in amber glass jars ofsufficient volume to hold 1900 cm3of the liquid.8.2 Fresh test solutions shall be prepared on a daily basis. Atno t
21、ime throughout the entire test period shall test pieces beallowed to remain in the same solution for more than 48 h.8.2.1 If the test period is to be 166 h or greater, the testsolutions shall be left unchanged for one day per week.8.3 Total residual chlorine levels of at least one freshlyprepared av
22、ailable chlorine and monochloramine solution shallbe determined weekly.8.4 Test solutions are heated in loosely sealed amber glassjars in a suitable water bath or hot forced-air oven to 70 6 2C(158 6 4F) prior to transferring them into test vessels inaccordance with Section 9.8.4.1 An acceptable alt
23、ernative method is the use of a glasscontainer of sufficient volume to prepare a large batch of testsolution capable of filling all test vessels with 1900 cm3ofsolution each. Prior to filling the test vessels, the liquid shall bestirred and checked with an immersion thermometer to ensurethat the spe
24、cified test temperature has been reached throughoutthe batch.8.5 Preparation of Standard Test Liquids and Solutions:8.5.1 Reagent WaterDistilled or deionized water (Type IIIor purer, see Specification D 1193) is heated to the testtemperature in a loosely sealed amber glass jar and transferredto the
25、test vessel.8.5.2 Available Chlorine Test SolutionA volume of 1900cm3of distilled or deionized water (Type III or purer, seeSpecification D 1193) is heated to the test temperature in aloosely sealed amber glass jar and 0.9 cm3of sodium hy-pochlorite solution with 10 % minimum total residual chlorine
26、7and 7.0 cm3of phosphate buffer solution8(pH 7.0) are thenadded, using a graduated pipet. The glass jar is again condi-tioned for 10 6 1 min at the specified test temperature and thesolution transferred into the test vessel. Solution strength shallbe 50 ppm (mg/L) of total residual chlorine determin
27、ed inaccordance with Test Methods D 1253, Section 10. The deter-mination of free available chlorine residual and combinedavailable chlorine residual for informational purposes is op-tional.8.5.2.1 Chloramine T shall not be used as a replacement forany of the reagents specified in the preparation of
28、the testsolutions.8.5.2.2 Sodium hypochlorite solutions are not stable andwill change their concentration in storage. It is thereforerecommended to use fresh solutions or store solutions in thedark under refrigeration (about 5C (41F). The concentrationof solutions stored for any length of time shoul
29、d be confirmedby determining their total residual chlorine level in accordancewith Test Methods D 1253, Section 10. If the concentration haschanged, the necessary adjustments shall be made in thepreparation of the test solutions.8.5.3 Monochloramine Test SolutionA volume of 1900cm3of distilled or de
30、ionized water (Type III or purer, seeSpecification D 1193) is heated to the test temperature in aloosely sealed amber glass jar and 0.9 cm3of sodium hy-pochlorite solution with 10 % minimum total residual chlorine7and 4.0 cm3of phosphate buffer solution8(pH 7.0) are thenadded, using a graduated pipe
31、tte. The glass jar is conditionedfor 10 6 1 min at the specified test temperature followed by theaddition of 2.7 cm31N ammonium hydroxide9and 8.0 cm3ofphosphate buffer solution8(pH 7.0). The glass jar is againconditioned at the test temperature for 10 6 1 min and thefinished solution transferred to
32、the test vessel. Solution strength4A suitable flask can be obtained under Catalog No. 4960-2L from Corning, Inc.,County Rd. 64, Big Flats, NY 14814.5A suitable heating mantle can be obtained under Catalog No. EM-2000C fromElectrothermal, Inc., 275 Morristown Rd., Gillette, NJ 07933.6A suitable conde
33、nser can be obtained under Catalog No. 2560-500 fromCorning, Inc., County Rd. 64, Big Flats, NY 14814.7A suitable solution can be obtained under Catalog No. 7216 from Mallinckrodt,Inc., Highway 68 Bypass, Paris, KY 40361.8A suitable buffer solution can be obtained under Catalog No. 27002 from HachCo
34、., 5600 Lindburgh Drive, Loveland, CO 80538.9A suitable solution can be obtained under Catalog No. V 044 from Mallinck-rodt, Inc., Highway 68 Bypass, Paris, KY 40361.TABLE 1 Immersion Periods, h22 67046 100670 1342166 2186334 4366502D6284022shall be 50 ppm (mg/L) of total residual chlorine determine
35、d inaccordance with Test Methods D 1253, Section 10. The deter-mination of free available chlorine residual and combinedavailable chlorine residual for informational purposes is op-tional.8.5.3.1 Chloramine T shall not be used as a replacement forany of the reagents specified in the preparation of t
36、he testsolutions.8.5.3.2 Sodium hypochlorite solutions are not stable andwill change their concentration in storage. It is thereforerecommended to use fresh solutions or store solutions in thedark under refrigeration (about 5C (41F). The concentrationof solutions stored for any length of time should
37、 be confirmedby determining their total residual chlorine level in accordancewith Test Methods D 1253, Section 10. If the concentration haschanged, the necessary adjustments shall be made in thepreparation of the test solutions.9. Test Specimens9.1 Unless otherwise specified, test pieces shall be pr
38、eparedin accordance with Practice D 3182 or Practice D 3183.9.2 Dimensions of standard test pieces shall be as indicatedin Table 2. Type 2 specimens shall be cut from standardvulcanized sheets prepared in accordance with PracticeD 3182. Sheets for Type 1 and 3 specimens shall be vulcanizedin molds m
39、odified for cavity depth, but having otherwise thesame dimensions as specified in Practice D 3182 (Fig. 1, 2, 3,or 4).9.3 Type 1 specimens are preferred for accelerated testing.Types 2 and 3 specimens may be specified by mutual agree-ment between the producer and the purchaser.9.4 The same test piec
40、es are used to determine changes inmass, volume, hardness, and visual rating.9.5 If rubber parts or nonstandard test pieces are used, theprocedure shall be adjusted to maintain a minimum volume of20 cm3of test solutions per 1 cm2of test piece surface area.Data obtained on test pieces of different or
41、iginal thicknessesare not comparable.10. Procedure for Change in Mass10.1 See Test Method D 471, Section 10.10.2 Test three test pieces of a single composition. Calculatethe test results of the three test pieces in accordance with Eq 1and average the results.10.3 Weigh each test piece in air to the
42、nearest 1 mg, recordthe mass as M1, and mount three test pieces on a glass rod sothat a minimum of 6-mm (0.25-in.) separation is maintainedbetween the test pieces through the use of spacers, for example,perforated glass beads. It is important that the materials used tosuspend and separate the test p
43、ieces do not affect the test liquidand the rubber.10.4 Place the test piece setup in the test vessel (see 9.1)containing the test liquid for the specified time and removeeach test piece from the flask at the end of the immersionperiod.10.5 Cool the test pieces to room temperature by transfer-ring th
44、em into a cool and clean portion of the test liquid for 30min. After removal from the liquid, lightly blot the test piecesdry with lint-free paper, place them in a tared stopperedweighing bottle, weigh each test piece to the nearest 1 mg,record the mass as M2.10.6 Return the test pieces to the cool
45、and clean portion ofthe test liquid before proceeding with hardness testing andvisual rating. After completing all testing return the test piecesto the test vessel with the same test liquid, if data are desiredon progressive changes that occur with increasing immersiontimes.10.7 It is important that
46、 each manipulation following re-moval of the test pieces from the test liquid takes placepromptly with the least possible lapse in time.10.8 Prepared fresh test liquids daily in accordance with 8.2,except as described in 2.1. Discard the old solutions afterevaluating turbidity and add fresh solution
47、s to the test vessel(without removal of the test pieces).11. Procedure for Change in Volume11.1 See Test Method D 471, Section 11.11.2 Test three test pieces of a single composition. Calculatethe test results of the three test pieces in accordance with Eq 2and average the results.11.3 Weight each te
48、st piece in air to the nearest 1 mg andrecord the mass as M1. Then obtain the mass M2of each testpiece immersed in distilled water or methanol (Note 1) at roomtemperature.NOTE 1Methanol may be employed in place of water if the removalof air bubbles from the test piece surface is a problem.11.4 Quick
49、ly blot the test pieces dry using lint-free paper,mount three test pieces on a glass rod in accordance with 10.3,and place the test piece setup in the test vessel (see 9.1)containing the test liquid for the specified time.11.5 Remove each test piece from the flask at the end of theimmersion period and cool to room temperature in a cool andclean portion of the test liquid for 30 min. Lightly blot each testpiece dry with lint-free paper, place it in a tared stopperedweighing bottle, weigh to the nearest 1 mg, and record the massas M3. Remove each test piece from
