1、Designation: D6601 02 (Reapproved 2008) D6601 12Standard 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 ye
2、ar 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 oscilla
3、ting shear rheometer for measuring after cure dynamic properties atpredetermined temperature(s) below the cure temperature.1.2 Specified cure conditions that approximate a “static cure” also are covered to minimize effects on cured rubber compounddynamic properties. This test method is not intended
4、to replace Test Method D5289.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations p
5、rior to use.1.4 WarningCompounds based on silicone or fluoroelastomers may have high levels of thermal contraction or poor adhesionto the dies when cooled after the cure portion of this test method, causing slippage during strain sweeps. If this occurs, the resultswill not be reliable.2. Referenced
6、Documents2.1 ASTM Standards:2D1349 Practice for RubberStandard Temperatures for TestingD4483 Practice for Evaluating Precision for Test Method Standards in the Rubber and Carbon Black Manufacturing IndustriesD5289 Test Method for Rubber PropertyVulcanization Using Rotorless Cure MetersD5992 Guide fo
7、r Dynamic Testing of Vulcanized Rubber and 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 peak amplitude shear stress to peak amplitude shear strain; mathematically,G* = (G2 + G“2)1/2.3.1.2
8、complex torque, S*, nthe peak amplitude torque response measured by a reaction torque transducer for a sinusoidallyapplied strain; mathematically, S* is computed by S* = (S2 + S“2)1/2.3.1.3 dynamic cure, nany cure condition which oscillates or moves the die.3.1.4 elastic torque, S, nthe peak amplitu
9、de torque component, which is in phase with a sinusoidally applied strain.3.1.5 loss angle, , nthe phase angle by which the complex torque (S*) leads a sinusoidally applied strain.3.1.6 loss factor, tan , nthe ratio of loss modulus to storage modulus, or the ratio of viscous torque to elastic torque
10、;mathematically, tan = G“/G = S“/S.3.1.7 loss shear modulus, G“, nthe component of applied stress that is 90 out-of-phase with the shear strain, divided by thestrain.3.1.8 static cure, nthe cure conditions of 0.0 arc strain and 0.0 Hz in frequency, that is, no movement of the dies during thecure tes
11、t.1 This test method is under the jurisdiction of ASTM Committee D11 on Rubber and is the direct responsibility of Subcommittee D11.14 on Time andTemperature-Dependent Physical Properties.Current edition approved May 1, 2008Dec. 1, 2012. Published June 2008January 2013. Originally approved in 2000.
12、Last previous edition approved in 20022008 asD6601 02.D6601 02 (2008). DOI: 10.1520/D6601-02R08.10.1520/D6601-12.2 For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to t
13、he standards Document Summary page on the ASTM website.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes a
14、ccurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United
15、States13.1.9 storage shear modulus, G, nthe component of applied stress that is in phase with the shear strain, divided by the strain.3.1.10 viscous torque, S“, nthe peak amplitude torque component, which is 90 out of phase with a sinusoidally applied strain.4. Summary of Test Method4.1 A rubber tes
16、t specimen is contained in a die cavity that is closed and maintained at an elevated cure temperature. The cavityis formed by two dies, one of which is oscillated through a rotary amplitude. This action produces a sinusoidal torsional strain inthe test specimen resulting in a sinusoidal torque, whic
17、h measures the viscoelastic changes of the test specimen as it cures. Thetest specimen must be a unvulcanized rubber compound containing curatives. A controlled limited strain is applied during cure toprevent effecting the aftercure properties.4.2 After a predetermined cure time, the temperature is
18、reduced and dynamic property measurements can be based on a strainsweep in which the strain amplitude is programmed to change in steps under constant frequency and temperature, a frequencysweep in which the frequency is programmed to change in steps under constant strain amplitude and temperature, o
19、r, a temperaturesweep in which the temperature is programmed to decrease under constant strain amplitude and frequency conditions.4.3 For an after-cure strain sweep, the instrument is typically programmed to increase the strain with each subsequent stepchange. This is done to minimize the influence
20、of prior test conditions on subsequent test steps. Typically two repeat strain sweepsmay be programmed consecutively to quantify the Payne Effect,3 which is the reduction in dynamic storage modulus from strainsoftening of the rubber vulcanizate.5. Significance and Use5.1 This test method is used to
21、determine the vulcanization characteristics of (vulcanizable) rubber compounds under selectedtest conditions of strain and frequency which do not significantly affect the cured dynamic properties. In the same test, this testmethod also will measure the dynamic properties of the vulcanizate at temper
22、atures significantly below the cure temperature. Theselower temperature measurements are necessary in order to more effectively relate to rubber product service conditions.5.2 This test method may be used for quality control in rubber manufacturing processes and for research and developmenttesting o
23、f rubber compounds containing curatives. This test method also may be used for evaluating cure and dynamic propertydifferences resulting from the use of different compounding ingredients.5.3 For additional information regarding the significance of dynamic testing of vulcanized rubber, the reader may
24、 wish toreference Guide D5992.6. Apparatus6.1 Torsion Strain Rotorless Oscillating Rheometer with a Sealed CavityThis type of rheometer measures the elastic torqueS and viscous torque S“ produced by oscillating angular strain of set amplitude and frequency in a completely closed and sealedtest cavit
25、y.6.2 Sealed Die CavityThe sealed die cavity is formed by two conical surface dies. In the measuring position, the two dies arefixed a specified distance apart so that the cavity is closed and sealed (see Fig. 1).6.3 Die GapFor the sealed cavity, no gap should exist at the edges of the dies. At the
26、center of the dies, the die gap shall beset at 0.45 6 0.05 mm.6.4 Die Closing MechanismFor the sealed cavity, a pneumatic cylinder or other device shall close the dies and hold themclosed during the test with a force not less than 11 kN (2500 lbf).6.5 Die Oscillating SystemThe die oscillating system
27、 consists of a direct drive motor, which imparts a torsional oscillatingmovement to the lower die in the cavity plane.6.5.1 The oscillation amplitude can be varied, but a selection of 0.2 arc (62.8 % shear strain) is preferred for the cure test whilestrains from 61 to 6100 % are preferred for the af
28、ter-cure strain sweeps. The oscillation frequency can be varied between 0.03Hz and 30 Hz.6.6 Torque Measuring SystemThe torque measuring system shall measure the resultant shear torque.6.6.1 The torque measuring device shall be rigidly coupled to the upper die, any deformation between the die and de
29、vice shallbe negligibly small, and the device shall generate a signal, which is proportional to the torque. The total error resulting from zeropoint error, sensitivity error, linearity, and repeatability errors shall not exceed 1 % of the selected measuring range.6.6.2 The torque recording device sh
30、all be used to record the signal from the torque measuring device and shall have a responsetime for full scale deflection of the torque scale of 1 s or less. The torque shall be recorded with an accuracy of 6 0.5 % of therange. Torque recording devices may include analog chart recorders, printers, p
31、lotters, or computers.3 A.R. Payne, J. Polymer Sci., 6, 57 (1962).D6601 1226.6.3 A reference torque device is required to calibrate the torque measurement system. A torque standard may be used tocalibrate the torque measuring system at the selected angular displacement by clamping a steel torsion ro
32、d to the oscillating andthe torque measuring dies of the torsion shear rheometer (see Fig. 2). The reference values for angular displacement andcorresponding torque shall be established by the manufacturer for each torque standard.6.7 Reference Test TemperatureThe standard reference test temperature
33、 for cure shall be either 140C, 160C, or 180C whiledynamic property measurements after-cure (dynamic property measurements made after completion of the cure test) should bemade at either 100C or 60C. Tests may be carried out at other temperatures, if required. Other temperatures should be selectedin
34、 accordance with Practice D1349 when practical.6.8 Temperature Control SystemThis system shall permit the reference temperature to be varied between 40C and 220C withan accuracy of 60.3C or better.6.8.1 The dies shall heat to the set point temperature in 1.0 min or less from closure of the test cavi
35、ty. Once the initial heatingup time has been completed, die temperature shall not vary by more than 60.3C for the remainder of a cure test at a settemperature. When the set temperature is changed in a programmed temperature sweep or strain sweep, dynamic propertymeasurements should not be recorded u
36、ntil the die temperatures are within 60.3C of the new set temperature for at least 30 s.6.8.2 Temperature distribution within the test piece shall be as uniform as possible. Within the deformation zone, a toleranceof 61C of the average test piece temperature shall not be exceeded.6.8.3 Die temperatu
37、re is determined by a temperature sensor used for control. The difference between the die temperature andthe average test piece temperature shall not be more than 2C. Temperature measurement accuracy shall be 60.3C for the dietemperature sensor.FIG. 1 Typical Sealed Torsion Shear Rotorless Curemeter
38、D6601 1236.8.4 The upper and lower dies shall each be jacketed with forced air cooling devices in order to rapidly decrease thetemperature of the upper and lower dies after the cure test is completed.7. Test Specimen7.1 A test specimen taken from a sample shall be between 5 and 6 cm3 for the sealed
39、cavity oscillating rheometer. The specimenvolume should exceed the test cavity volume by a small amount, to be determined by preliminary tests. Typically, specimen volumeshould be 130 to 150 % of the test cavity volume. Once a target mass for a desired volume has been established, specimen massessho
40、uld be controlled to within 60.5 g for best repeatability. The initial test specimen shape should fit well within the perimeterof the test cavity.7.2 Compounded Rubber SpecimensTest specimens shall be taken from a rubber compound as required by the mixing methodor other sampling instructions. Only r
41、ubber compounds with curatives may be tested.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 in Table 1.8.2 Select from one of eight different after-cure dynamic test
42、ing conditions shown in Table 2.8.3 Program a test configuration which incorporates these conditions and store on the instrument computer operating system.8.4 Load the test configuration to run the test.8.5 Enter specimen identification.8.6 Wait until both dies are at the initial test temperature. O
43、pen the test cavity and visually check both upper and lower diesfor cleanliness. Clean the dies, if necessary. Place the test specimen on the center of the lower die and close the dies within 20s.9. Report9.1 Report the following information.9.1.1 A full description of the sample, or test specimen(s
44、), or both, including their origin.FIG. 2 Typical Torque Standard Calibration Device for Torsion Shear CuremetersD6601 1249.1.2 Type and model of oscillating rheometer.9.1.3 The frequency, strain, temperature and time for the cure test (if no strain, indicate “static cure”).9.1.4 Minimum torque (ML)
45、 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 decimal fraction 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 prop
46、erties are reported since no measurements are possible.9.1.5 The temperature, frequency and different strains applied in an after-cure strain sweep.9.1.6 The storage shear modulus G in kPa and the percent strain for each step in the programmed strain sweep.9.1.7 The loss shear modulus G“ in kPa and
47、the percent strain for each step in the programmed strain sweep.9.1.8 The tangent delta (tan ) and the percent strain for each step in the programmed strain sweep.9.1.9 If two consecutive strain sweeps are programmed, the results from both of these strain sweeps should be recorded(reference the Payn
48、e Effect discussed in 4.3).10. Precision and Bias10.1 These precision statements have been prepared in accordance with Practice D4483. Refer to this practice for terminologyand other statistical details.10.2 The precision results in this precision and bias section give an estimate of the precision o
49、f this test method with thematerials used in the particular interlaboratory program described below. The precision parameters should not be used foracceptance or rejection testing of any group of materials without documentation that they are applicable to those particularmaterials and the specific testing protocols of the test method.10.3 A type 1 interlaboratory precision program was conducted. Both repeatability and reproducibility represent short term(daily) testing conditions. The testing was performed using two opera
