ASTM_C_1241_-_14.pdf

Designation:C124114Standard 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 number 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 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-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.NOTE1A 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 and 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 method: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 cure,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 results 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 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 volatiles 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 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 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 Subcommittee 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 Customer 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 Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 7.4 Determine the density(Ds)in grams per millilitre offresh sealant by Test Method D1475.Record the averagedensity(Ds)of three determinations.NOTE2It is very important that the volume of the weight-per-galloncup be accurately 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 nearest0.001 g.7.6 Extrude a set of sealant specimens containing two beadsapproximately 3 mm(18in.)in diameter and 38 mm(112in.)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.NOTE3Hand