1、Designation: D6601 15Standard 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,
2、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 mea
3、suring 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
4、.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 WarningCom
5、pounds 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 Standard
6、s: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 Vulcanize
7、d 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+ G“2)1/2.3.1.2 complex torque, S*, nthe peak ampl
8、itude torqueresponse measured by a reaction torque transducer for asinusoidally applied strain; mathematically, S* is computed byS* =(S2+ S“2)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 w
9、ith 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
10、 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 componen
11、t 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 an
12、d 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
13、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 Subc
14、ommittee D11.10 on Physical Testing.Current edition approved Nov. 1, 2015. Published December 2015. Originallyapproved in 2000. Last previous edition approved in 2012 as D6601 12. DOI:10.1520/D6601-15.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Servi
15、ce 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 States14.2 After a predetermined cure time, the tempe
16、rature 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 andtemperat
17、ure, 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 minimize the infl
18、uence of prior testconditions on subsequent test steps. Typically two repeat strainsweeps may be programmed consecutively to quantify thePayne Effect,3which is the reduction in dynamic storagemodulus from strain softening of the rubber vulcanizate.5. Significance and Use5.1 This test method is used
19、to determine the vulcanizationcharacteristics of (vulcanizable) rubber compounds under se-lected test conditions of strain and frequency which do notsignificantly affect the cured dynamic properties. In the sametest, this test method also will measure the dynamic propertiesof the vulcanizate at temp
20、eratures significantly below the curetemperature. These lower temperature measurements are nec-essary in order to more effectively relate to rubber productservice conditions.5.2 This test method may be used for quality control inrubber manufacturing processes and for research and develop-ment testin
21、g of rubber compounds containing curatives. Thistest method also may be used for evaluating cure and dynamicproperty differences resulting from the use of different com-pounding ingredients.5.3 For additional information regarding the significance ofdynamic testing of vulcanized rubber, the reader m
22、ay wish toreference Guide D5992.6. Apparatus6.1 Torsion Strain Rotorless Oscillating Rheometer with aSealed CavityThis type of rheometer measures the elastictorque S and viscous torque S“ produced by oscillating angularstrain of set amplitude and frequency in a completely closedand sealed test cavit
23、y.6.2 Sealed Die CavityThe sealed die cavity is formed bytwo conical surface dies. In the measuring position, the twodies are fixed a specified distance apart so that the cavity isclosed and sealed (see Fig. 1).6.3 Die GapFor the sealed cavity, no gap should exist atthe edges of the dies. At the cen
24、ter of the dies, the die gap shallbe set at 0.45 6 0.05 mm.6.4 Die Closing MechanismFor the sealed cavity, a pneu-matic cylinder or other device shall close the dies and holdthem closed during the test with a force not less than 11 kN(2500 lbf).6.5 Die Oscillating SystemThe die oscillating systemcon
25、sists of a direct drive motor, which imparts a torsionaloscillating movement to the lower die in the cavity plane.6.5.1 The oscillation amplitude can be varied, but a selec-tion of 0.2 arc (62.8 % shear strain) is preferred for the curetest while strains from 61to6100 % are preferred for theafter-cu
26、re strain sweeps. The oscillation frequency can bevaried between 0.03 Hz and 30 Hz.6.6 Torque Measuring SystemThe torque measuring sys-tem shall measure the resultant shear torque.6.6.1 The torque measuring device shall be rigidly coupledto the upper die, any deformation between the die and devicesh
27、all be negligibly small, and the device shall generate a signal,which is proportional to the torque. The total error resultingfrom zero point error, sensitivity error, linearity, and repeat-ability errors shall not exceed 1 % of the selected measuringrange.6.6.2 The torque recording device shall be
28、used to record thesignal from the torque measuring device and shall have a3A.R. Payne, J. Polymer Sci., 6, 57 (1962).FIG. 1 Typical Sealed Torsion Shear Rotorless CuremeterD6601 152response time for full scale deflection of the torque scale of 1s or less. The torque shall be recorded with an accurac
29、y of 60.5 % of the range. Torque recording devices may includeanalog chart recorders, printers, plotters, or computers.6.6.3 A reference torque device is required to calibrate thetorque measurement system. A torque standard may be used tocalibrate the torque measuring system at the selected angulard
30、isplacement by clamping a steel torsion rod to the oscillatingand the torque measuring dies of the torsion shear rheometer(see Fig. 2). The reference values for angular displacement andcorresponding torque shall be established by the manufacturerfor each torque standard.6.7 Reference Test Temperatur
31、eThe standard referencetest temperature for cure shall be either 140C, 160C, or180C while dynamic property measurements after-cure (dy-namic property measurements made after completion of thecure test) should be made at either 100C or 60C. Tests maybe carried out at other temperatures, if required.
32、Other tem-peratures should be selected in accordance with PracticeD1349 when practical.6.8 Temperature Control SystemThis system shall permitthe reference temperature to be varied between 40C and220C with an accuracy of 60.3C or better.6.8.1 The dies shall heat to the set point temperature in 1.0min
33、 or less from closure of the test cavity. Once the initialheating up time has been completed, die temperature shall notvary by more than 60.3C for the remainder of a cure test ata set temperature. When the set temperature is changed in aprogrammed temperature sweep or strain sweep, dynamicproperty m
34、easurements should not be recorded until the dietemperatures are within 60.3C of the new set temperature forat least 30 s.6.8.2 Temperature distribution within the test piece shall beas uniform as possible. Within the deformation zone, a toler-ance of 61C of the average test piece temperature shall
35、not beexceeded.6.8.3 Die temperature is determined by a temperature sensorused for control. The difference between the die temperatureand the average test piece temperature shall not be more than2C. Temperature measurement accuracy shall be 60.3C forthe die temperature sensor.6.8.4 The upper and low
36、er dies shall each be jacketed withforced air cooling devices in order to rapidly decrease thetemperature of the upper and lower dies after the cure test iscompleted.7. Test Specimen7.1 A test specimen taken from a sample shall be between 5and 6 cm3for the sealed cavity oscillating rheometer. Thespe
37、cimen volume should exceed the test cavity volume by asmall amount, to be determined by preliminary tests. Typically,specimen volume should be 130 to 150 % of the test cavityvolume. Once a target mass for a desired volume has beenestablished, specimen masses should be controlled to within60.5 g for
38、best repeatability. The initial test specimen shapeshould fit well within the perimeter of the test cavity.7.2 Compounded Rubber SpecimensTest specimens shallbe taken from a rubber compound as required by the mixingmethod or other sampling instructions. Only rubber com-pounds with curatives may be t
39、ested.7.2.1 The rubber compound shall be in the form of a sheet,at room temperature, and as free of air as possible.8. Procedure8.1 Select from one of six different cure conditions shown inTable 1.8.2 Select from one of eight different after-cure dynamictesting conditions shown in Table 2.8.3 Progra
40、m a test configuration which incorporates theseconditions and store on the instrument computer operatingsystem.FIG. 2 Typical Torque Standard Calibration Device for TorsionShear CuremetersTABLE 1 Test Conditions for Cure TestANOTE 1Cure properties should be measured in accordance with TestMethod D52
41、89.Cure Condition No. Temperature, C Frequency, Hz Strain, Arc.1 140 1.67 0.22 160 1.67 0.23 180 1.67 0.24 140 0 05 160 0 06 180 0 0APlease note that cure conditions of 0.2 arc strain and 1.67 Hz frequency mayinfluence post cure propertiesD6601 1538.4 Load the test configuration to run the test.8.5
42、Enter specimen identification.8.6 Wait until both dies are at the initial test temperature.Open the test cavity and visually check both upper and lowerdies for cleanliness. Clean the dies, if necessary. Place the testspecimen on the center of the lower die and close the dieswithin 20 s.9. Report9.1
43、Report the following information.9.1.1 Afull description of the sample, or test specimen(s), orboth, including their origin.9.1.2 Type and model of oscillating rheometer.9.1.3 The frequency, strain, temperature and time for thecure test (if no strain, indicate “static cure”).9.1.4 Minimum torque (ML
44、) as dNm, maximum torque (MH)as dNm, time to scorch as indicated by time to one unit rise (indNm units) from minimum torque (tS1) in minutes and decimalfraction of a minute, and time to 10 %, 50 %, and 90 % state ofcure in minutes and decimal fraction of a minute.NOTE 1For static cure, no cure prope
45、rties are reported since nomeasurements are possible.9.1.5 The temperature, frequency and different strains ap-plied in an after-cure strain sweep.9.1.6 The storage shear modulus G in kPa and the percentstrain for each step in the programmed strain sweep.9.1.7 The loss shear modulus G“ in kPa and th
46、e percentstrain for each step in the programmed strain sweep.9.1.8 The tangent delta (tan ) and the percent strain foreach step in the programmed strain sweep.9.1.9 If two consecutive strain sweeps are programmed, theresults from both of these strain sweeps should be recorded(reference the Payne Eff
47、ect discussed in 4.3).10. Precision and Bias10.1 These precision statements have been prepared inaccordance with Practice D4483. Refer to this practice forterminology and other statistical details.10.2 The results in this precision and bias section give anestimate of the precision of this test metho
48、d with the materialsused in the interlaboratory program described below. Theprecision parameters should not be used for acceptance orrejection testing of any group of materials without documen-tation that they are applicable to those particular materials andthe specific testing protocols of the test
49、 method.10.3 A type 1 interlaboratory precision program was con-ducted. Both repeatability and reproducibility represent shortterm (daily) testing conditions. The testing was performedusing one operator in each laboratory performing the test twiceon each material on each of two days (total of four tests).Atestresult is the value obtained from a single determination.Acceptable difference values were not measured.10.4 The results of the precision calculations for this test aregiven. The materials are arranged in ascending
