1、Designation: C1241 14Standard Test Method forVolume Shrinkage of Latex Sealants During Cure1This standard is issued under the fixed designation C1241; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A num
2、ber in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method covers a laboratory procedure fordetermining volume shrinkage, which occurs during cure, of alatex sealant.1.2 The values
3、 stated in SI units are to be regarded as thestandard. The values given in parentheses are provided forinformation only.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-pr
4、iate safety and health practices and determine the applica-bility of regulatory limitations prior to use.NOTE 1A related ISO standard is ISO 10563. The user shouldcompare to determine how it differs from this test method.2. Referenced Documents2.1 ASTM Standards:2C717 Terminology of Building Seals a
5、nd SealantsD1475 Test Method For Density of Liquid Coatings, Inks,and Related Products2.2 ISO Standards:3ISO 10563 Building ConstructionSealantsDeterminationof Change in Mass and Volume3. Terminology3.1 DefinitionsRefer to Terminology C717 for definitionsof the following terms used in this test meth
6、od: cure, joint,latex sealant, sealant, shrinkage (volume), and tooling.4. Summary of Test Method4.1 The sealant is extruded onto polyethylene release filmand weighed. After curing for 28 days, its volume shrinkage iscalculated using the sealants density, the percent weight lostduring the 28-day cur
7、e, and the density of water. The density ofthe sealant is determined by the weight-per-gallon cup proce-dure described in Test Method D1475.5. Significance and Use5.1 Shrinkage of a sealant, after application in a buildingjoint, is caused by loss of volatile components from the sealant.This loss res
8、ults in a decrease in volume and, hence, a changein the sealants shape. This change in shape, in someapplications, should be taken into consideration for acceptablejoint appearance and geometry.5.2 The shrinkage value obtained by this test method helpspredict the appearance and geometry of the cured
9、 sealant in abuilding joint and is helpful in determining the amount andtype of tooling to be done during installation of the sealant.5.3 Latex sealants cure primarily through water evapora-tion. They may also contain small amounts of other volatilecomponents. However, in this test method all volati
10、les aretreated as water. This assumption still provides a meaningfulshrinkage value since the small quantities of other volatiles andtheir differences in density from that of water do not signifi-cantly affect the usefulness of the result obtained.6. Apparatus6.1 Polyethylene FilmThree sheets, each
11、about 51 by 51mm (2 by 2 in.) by 0.127 mm (5 mil) thick.6.2 Weight-per-Gallon Cup, 80 to 90 mL capacity.6.3 Constant Temperature Bath or Room, held at 23 62.0C (73 6 3.6F).6.4 Forceps.6.5 Distilled Water.7. Procedure7.1 Standard Conditions are as defined in TerminologyC717.7.2 Condition the sealant
12、to be tested in a closed containerat standard conditions for at least 24 h.7.3 Condition approximately 2 L of distilled water atstandard conditions for at least 24 h.1This test method is under the jurisdiction ofASTM Committee C24 on BuildingSeals and Sealants and is the direct responsibility of Sub
13、committee C24.20 onGeneral Test Methods.Current edition approved Feb. 1, 2014. Published March 2014. Originallyapproved in 1993. Last previous edition approved in 2009 as C1241 00(2009).DOI: 10.1520/C1241-14.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Custome
14、r Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036.Copyright ASTM International, 100 Barr Harbor
15、Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States17.4 Determine the density (Ds) in grams per millilitre offresh sealant by Test Method D1475. Record the averagedensity (Ds) of three determinations.NOTE 2It is very important that the volume of the weight-per-galloncup be accurately
16、 determined according to the calibration proceduredescribed in Test Method D1475. Use distilled water from 7.3. Determinethe distilled water density by measuring its temperature to the nearest 1Cat the time of cup calibration and use of Table 1.7.5 Weigh each of the polyethylene sheets to the neares
17、t0.001 g.7.6 Extrude a set of sealant specimens containing two beadsapproximately 3 mm (18 in.) in diameter and 38 mm (112 in.)long onto a weighed polyethylene sheet.7.7 Immediately weigh the sheet with sealant and determinethe net weight of fresh sealant to the nearest 0.001 g.NOTE 3Handling the sh
18、eets with bare hands will leave fingerprints,hence, handling only with forceps is recommended.7.8 Prepare and weigh two more sets of sealant specimensas in 7.6 and 7.7.7.9 Cure the sealant specimens, while still attached to thepolyethylene, for 28 days at standard conditions. Protect thespecimens fr
19、om picking up dust.7.10 After the 28-day cure period, weigh each sheet withsealant and determine the net weight of each set of sealantspecimens to the nearest 0.001 g.8. Calculation8.1 Calculate the percent weight loss (% Wl) from each setof specimens as follows:% Wl 5Wf2 WcWf3100 (1)where:Wf= net w
20、eight of fresh sealant, g (7.7), andWc= net weight of sealant after 28 days cured (7.10).8.2 Calculate the average percent weight loss (% Wl)ofthethree sets of sealant specimens.8.3 Calculate the percent volume shrinkage of the sealant asfollows:% volume shrinkage 5Ds3% Wl0.9976(2)where:Ds= average
21、density of fresh sealant, g/mL (7.4),% Wl= average percent weight loss (8.2), and0.9976 = density of water at 23C, g/mL (Table 1).9. Report9.1 Report the following information for each sealant tested:9.1.1 Identification of the sealant, and9.1.2 Percent volume shrinkage as calculated in 8.3.10. Prec
22、ision and Bias410.1 PrecisionThe precision of this test method is basedon the results of five laboratories testing three materials intriplicate.10.1.1 RepeatabilityIn the future use of this test method,the difference between two test results obtained by the sameoperator on the same material will be
23、expected to exceed0.771 % only about 5 % of the time.10.1.2 ReproducibilityIn future use of this test method,the difference between two test results obtained by differentoperators in different laboratories on the same material will beexpected to exceed 1.862 % only about 5 % of the time.10.2 BiasSin
24、ce there is no accepted reference materialsuitable for determining the bias for this test method forvolume shrinkage, bias has not been determined.11. Keywords11.1 latex sealant; sealant; shrinkage (volume); tooling4Supporting data have been filed at ASTM International Headquarters and maybe obtaine
25、d by requesting Research Report RR:C24-1044.TABLE 1 Absolute Density of Water, g/mLC Density15 0.99912716 0.99897117 0.99877218 0.99862319 0.99843320 0.99823121 0.99802022 0.99779823 0.99756624 0.99732425 0.99707226 0.99681127 0.99654028 0.99626029 0.99597230 0.995684C1241 142ASTM International take
26、s 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 any such patent rights, and the riskof infringement of such rights, are entirely their own res
27、ponsibility.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 are invited either for revision of this standard or for additional standardsand should be address
28、ed 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 received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the
29、 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). Permission rights to photocopy the standard may also be secured from the ASTM website (www.astm.org/COPYRIGHT/).C1241 143
