ASTM_D_6601_-_12.pdf

Designation:D660112Standard Test Method forRubber PropertiesMeasurement of Cure and After-CureDynamic Properties Using a Rotorless Shear Rheometer1This standard is issued under the fixed designation D6601;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 the use of a rotorless oscillatingshear rheometer for measuring after cure dynamic properties atpredetermined temperature(s)below the cure temperature.1.2 Specified cure conditions that approximate a“staticcure”also are covered to minimize effects on cured rubbercompound dynamic properties.This test method is not in-tended to replace Test Method D5289.1.3 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.1.4 WarningCompounds based on silicone or fluoroelas-tomers may have high levels of thermal contraction or pooradhesion to the dies when cooled after the cure portion of thistest method,causing slippage during strain sweeps.If thisoccurs,the results will not be reliable.2.Referenced Documents2.1 ASTM Standards:2D1349 Practice for RubberStandard Conditions for Test-ingD4483 Practice for Evaluating Precision for Test MethodStandards in the Rubber and Carbon Black ManufacturingIndustriesD5289 Test Method for Rubber PropertyVulcanizationUsing Rotorless Cure MetersD5992 Guide for Dynamic Testing of Vulcanized Rubberand Rubber-Like Materials Using Vibratory Methods3.Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 complex shear modulus,G*,nthe ratio of peakamplitude shear stress to peak amplitude shear strain;mathematically,G*=(G2+G2)1/2.3.1.2 complex torque,S*,nthe peak amplitude torqueresponse measured by a reaction torque transducer for asinusoidally applied strain;mathematically,S*is computed byS*=(S2+S2)1/2.3.1.3 dynamic cure,nany cure condition which oscillatesor moves the die.3.1.4 elastic torque,S,nthe peak amplitude torquecomponent,which is in phase with a sinusoidally appliedstrain.3.1.5 loss angle,nthe phase angle by which thecomplex torque(S*)leads a sinusoidally applied strain.3.1.6 loss factor,tan,nthe ratio of loss modulus tostorage modulus,or the ratio of viscous torque to elastictorque;mathematically,tan =G/G=S/S.3.1.7 loss shear modulus,G,nthe component of appliedstress that is 90 out-of-phase with the shear strain,divided bythe strain.3.1.8 static cure,nthe cure conditions of 0.0 arc strainand 0.0 Hz in frequency,that is,no movement of the diesduring the cure test.3.1.9 storage shear modulus,G,nthe component ofapplied stress that is in phase with the shear strain,divided bythe strain.3.1.10 viscous torque,S,nthe peak amplitude torquecomponent,which is 90 out of phase with a sinusoidallyapplied strain.4.Summary of Test Method4.1 A rubber test specimen is contained in a die cavity thatis closed and maintained at an elevated cure temperature.Thecavity is formed by two dies,one of which is oscillated througha rotary amplitude.This action produces a sinusoidal torsionalstrain in the test specimen resulting in a sinusoidal torque,which measures the viscoelastic changes of the test specimenas it cures.The test specimen must be a unvulcanized rubbercompound containing curatives.A controlled limited strain isapplied during cure to prevent effecting the aftercure proper-ties.1This test method is under the jurisdiction of ASTM Committee D11 on Rubberand is the direct responsibility of Subcommittee D11.10 on Physical Testing.Current edition approved Dec.1,2012.Published January 2013.Originallyapproved in 2000.Last previous edition approved in 2008 as D6601 02(2008).DOI:10.1520/D6601-12.2For 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 4.2 After a predetermined cure time,the temperature isreduced and dynamic property measurements can be based ona strain sweep in which the strain amplitude is programmed tochange in steps under constant frequency and temperature,afrequency sweep in which the frequency is programmed tochange in steps under constant strain amplitude andtemperature,or,a temperature sweep in which the temperatureis programmed to decrease under constant strain amplitude andfrequency conditions.4.3 For an after-cure strain sweep,the instrument is typi-cally programmed to increase the strain with each subsequentstep change.This is done to minimiz