ASTM_D_7308_-_07_2012.pdf

Designation:D730807(Reapproved 2012)Standard Practice forSample Preparation of Thermoplastic Traffic MarkingMaterials1This standard is issued under the fixed designation D7308;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 practice covers the proper preparation of testspecimens of thermoplastic traffic marking materials obtainedto ensure test results are representative of the material beingtested.1.2 The values stated in SI units are to be regarded as thestandard.The values given in parentheses are for informationonly.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.2.Referenced Documents2.1 ASTM Standards:2D7307 Practice for Sampling of Thermoplastic Traffic Mark-ing Materials3.Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 thermoplastic traffc marking material,na highlyfilled 100%total solids highway marking material that whenheated to a molten state can be extruded or sprayed onto a roadsurface and when cooled forms a solid,durable delineator.4.Summary of Practice4.1 The thermoplastic traffic marking material is preparedfor the testing of various physical and chemical properties asoutlined in the governing specification by melting a sample ofthe marking material to its application temperature undercontinuous agitation.Depending upon the requirements of thegoverning specification the sample can then be exposed to therequired heating time and conditions prior to the preparation ofthe test specimens or the test specimens may be preparedimmediately after the material has reached application tem-peratures.4.2 If required by the governing specification that thesample be subjected to extended periods of heating prior to thepreparation of the test specimen in order to determine the effectof heat history upon various physical or chemical properties,the sample must be melted down in the prescribed manner priorto being subjected to such conditions.5.Significance and Use5.1 This practice provides a standard procedure for thepreparation of thermoplastic traffic marking material test speci-mens prior to testing for various properties as called for in thegoverning specification.Specimens that are prepared using thisstandard methodology yield test results that are consistent withthe material from which it was sampled.Test results fromspecimens can be used to determine compliance of the ther-moplastic traffic marking material to the specification.Thissample preparation guide can also be used by manufacturers ofthese materials to prepare specimens for testing to determinethe uniformity of thermoplastic traffic marking materials frombatch to batch.5.2 This practice does not address any issues related tospecific testing of the thermoplastic pavement marking mate-rials for any physical or chemical property.6.Apparatus6.1 Procedure A(Preferred):6.1.1 Stainless Steel 4000 ml Beaker,150 by 230-mmdiameter high.Alternatively an unlined 0.95 L(1 qt)or 3.48 L(1 gal)can may be used depending on the sample size.6.1.2 Heating Mantle of sufficient size.Note that aluminumfoil may be used to serve as somewhat of a gasket if an unlinedmetal can is to be used in the heating mantle in place of thestainless steel beaker.6.1.3 Temperature Indicator.6.1.4 Thermocouple,iron.1This practice is under the jurisdiction of ASTM Committee D01 on Paint andRelated Coatings,Materials,and Applications and is the direct responsibility ofSubcommittee D01.44 on Traffic Coatings.Current edition approved June 1,2012.Published August 2012.Originallyapproved in 2007.Last previous edition approved in 2007 as D7308 07.DOI:10.1520/D7308-07R12.2For 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 6.1.5 Mechanical Stirrer,capable of stirring.The stirrershould consist of two impellers with a diameter of approxi-mately 63.5 mm mounted on a 7.95-mm diameter shaft ofsufficient length.6.1.6 Aluminum Lid to cover the top of the container with aslot to clear the shaft of the mechanical stirrer and thethermocouple.6.1.7 Stainless Steel Ladles with a pouring spout,60-mlcapacity.6.1.8 Tachometer to measure shaft speed of the mechanicalmixer.6.2 Procedure B(Alternate):6.2.1 Hot Plate with a maximum temperature setting ofapproximately 550C and with sufficient top plate surface areaas to e