ASTM_C_731_-_15.pdf

Designation:C73115Standard Test Method forExtrudability,After Package Aging,of Latex Sealants1This standard is issued under the fixed designation C731;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 for thedetermination of extrudability of latex sealants after freeze-thaw and heat cycling.1.2 The values stated in metric(SI)units are to be regardedas the standard.The values given in parentheses are forinformation only.1.3 This standard does not purport to address all of thesafety problems,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.NOTE1Currently there is no ISO standard similar to this test method.2.Referenced Documents2.1 ASTM Standards:2C717 Terminology of Building Seals and Sealants3.Terminology3.1 Definitions:Refer to Terminology C717 for definitionsof the following terms used in this test method:latex sealant,sealant,standard conditions.4.Summary of Test Method4.1 After being subjected to 5 freeze-thaw cycles followedby 7 days of heat aging,the sealant is extruded under pressurefrom an air-powered caulking gun,and the extrudability ismeasured in grams per second.5.Significance and Use5.1 Extrudability measurements of latex sealants serve toindicate only their ease of application;they do not predict theperformance capability of the compound after installation.5.2 This test method also measures freeze-thaw and heatstability of such sealants.6.Apparatus6.1 Caulking Gun,air-powdered.6.2 Polyethylene Cartridge,6 fluid oz.and plunger.6.3 Polyethylene Cartridge Nozzle,64 mm(212in.)inlength with 3-mm(18-in.)orifice.6.4 Air Compressor,capable of producing 0.34 MPa(50psi).6.5 Freezer,capable of maintaining 17 6 1C(0 6 2F).6.6 Circulating Air Oven,capable of maintaining 50 6 1C(122 6 2F).6.7 Stop Watch,standard laboratory.6.8 Analytical Balance,accurate to 1 g.6.9 Jar,approximately 0.5 L(1-pt).6.10 Spatula.7.Sampling7.1 After conditioning as specified in 8.1,take the sealant tobe tested directly from a container as commercially supplied bythe manufacturer.8.Conditioning8.1 Subject the sealant in its original container to 5 freeze-thaw cycles,each cycle consisting of 16 h at 176 1C(0 62F)and 8 h at 23 6 1C(73.46 2F),followed by 7 days at50 6 1C(122 6 2F).8.2 Condition the sealant which is still in its originalcontainer,for a minimum of 5 days at standard conditions.8.3 Condition the polyethylene cartridge for a minimum of16 h at standard conditions.9.Procedure9.1 After conditioning,transfer the sealant from its con-tainer into the polyethylene cartridge either by gunning or withthe spatula.Avoid trapping air in the sealant during transfer.9.2 Place the filled cartridge in the air-powered caulkinggun and attach the cartridge nozzle.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 June 1,2015.Published July 2015.Originally approvedin 1972.Last previous edition approved in 2010 as C731 00(2010).DOI:10.1520/C0731-15.2For 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.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 9.3 Weigh the jar and record its tare weight.9.4 Gun the entire contents of the cartridge at 0.34 MPa(50psi)into the empty,tared,jar,using a stop watch to time theextrusion.9.5 Weigh the jar containing the sealant.10.Calculation10.1 Calculate the weight of sealant extruded by sub-tracting the tare weight of the jar from the weight obtained in9.5.10.2 Calculate the rate of extrudability as follows:Rate of extrudability5 w/t(1)where:w=weight of compound extruded,g,andt=elapsed time,s.11.Report11.1 Report the rate of extrudability in grams per second.12.Precision and Bias312.1 PrecisionThe precision calculations for this testmethod are based on the results of five laboratories testingthree materials,each in duplicate.The results are given inTable 1.12.2 BiasSince there is no accepted reference materialsuitable for determining the bias for this test method forextrudability,bias has not been determined.13.Keywords13.1 extrudability;freeze-thaw stability;heat stability;latexsealantASTM 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