1、Designation: D7605 11D7605 11 (Reapproved 2016)Standard Test Method forThermoplastic ElastomersMeasurement of Polymer MeltRheological Properties and Congealed Dynamic PropertiesUsing Rotorless Shear Rheometers1This standard is issued under the fixed designation D7605; the number immediately followin
2、g 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 cov
3、ers the use of a rotorless oscillating shear rheometer for the measurement of the flow properties ofpolymer melts and their respective congealed dynamic properties for thermoplastic elastomers (TPE) which includes thermoplasticvulcanizates (TPV). These flow properties and congealed dynamic propertie
4、s are related to factory processing and productperformance.1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is th
5、e responsibilityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D1349 Practice for RubberStandard Conditions for TestingD3896 Practice for Rubber From Sy
6、nthetic SourcesSamplingD4483 Practice for Evaluating Precision for Test Method Standards in the Rubber and Carbon Black Manufacturing IndustriesD6600 Practice for Evaluating Test Sensitivity for Rubber Test Methods3. Terminology3.1 Definitions:3.1.1 complex shear modulus, G*, nratio of peak amplitud
7、e shear stress to peak amplitude shear strain; mathematically, G*= (S*/Area)/Strain = (G2 + G”2)1/2.3.1.2 complex torque, S*, npeak 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 congeale
8、d thermoplastic, nthermoplastic polymer that when cooled from the melt state exhibits a substantial portion ofthe physical properties of the solid state.3.1.4 dynamic complex viscosity, *, nratio of the complex shear modulus, G* to the oscillation frequency, , in radians persecond.3.1.5 elastic torq
9、ue, S, npeak amplitude torque component which is in phase with a sinusoidally applied strain.3.1.6 loss angle, , nphase angle by which the complex torque (S*) leads a sinusoidally applied strain.3.1.7 loss factor, tan , nratio of loss modulus to storage modulus, or the ratio of viscous torque to ela
10、stic torque;mathematically, tan = G”/G = S”/S.3.1.8 loss shear modulus, G”, nratio of (viscous) peak amplitude shear stress to peak amplitude shear strain for the torquecomponent 90 out of phase with a sinusoidally applied strain; mathematically, G” = (S”/Area) /Peak Strain.1 This test method is und
11、er the jurisdiction of ASTM Committee D11 on Rubber and Rubber-like Materials and is the direct responsibility of Subcommittee D11.12 onProcessability Tests.Current edition approved Nov. 1, 2011Nov. 1, 2016. Published November 2011December 2016. Last previous edition approved in 20102011 as D7605 10
12、.D7605 11.DOI: 10.1520/D7605-11.10.1520/D7605-11R16.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.This docu
13、ment 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 accurately, ASTM recommends that users consult prior editions as
14、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 States13.1.9 real dynamic viscosity, , nratio of the loss shear
15、modulus, G” to the oscillation frequency, , in radians per second.3.1.10 storage shear modulus, G, nratio of (elastic) peak amplitude shear stress to peak amplitude shear strain for the torquecomponent in phase with a sinusoidally applied strain; mathematically, G = (S/Area) /Peak Strain.3.1.11 visc
16、ous torque, S”, npeak amplitude torque component which is 90 out of phase with a sinusoidally applied strain.4. Summary of Test Method4.1 A thermoplastic elastomer test specimen is contained in a sealed die cavity which is closed and maintained at an elevatedtemperature. The cavity is formed by two
17、dies, one of which is oscillated through a rotary amplitude. This action produces asinusoidal torsional strain in the test specimen resulting in a sinusoidal torque, which measures a viscoelastic quality of the testspecimen. The test specimen can be a thermoplastic elastomer such as a thermoplastic
18、vulcanizate (TPV), a styrenic blockedcopolymer (SBC), a copolyester, a thermoplastic polyurethane, a thermoplastic polyolefin, or other TPE forms.4.2 These viscoelastic measurements can be made based on (1), a frequency sweep in which the frequency is programmed tochange in steps under constant stra
19、in amplitude and temperature conditions, (2), a strain sweep in which the strain amplitude isprogrammed to change in steps under constant frequency and temperature conditions, or (3), a temperature sweep in which thetemperature is programmed to either increase or decrease under constant strain ampli
20、tude and frequency conditions. A timed testmay also be performed in which a sinusoidal strain is applied for a given time period under constant strain amplitude, frequencyand temperature conditions.4.2.1 For a frequency sweep test, the instrument is typically programmed to increase the frequency wit
21、h each subsequent stepchange. For a strain sweep test, the instrument is usually programmed to increase the strain amplitude with each subsequent stepchange. This is done to minimize the influence of prior test conditions on subsequent test steps. For temperature sweeps, thetemperature may be progra
22、mmed either to increase or decrease with each subsequent step change, depending on the effects to bestudied. The results from increasing frequency, strain amplitude or temperature may not be the same as results from decreasingthese test parameters.4.3 Rheological properties are measured for each set
23、 of frequency, strain and temperature conditions. These properties can bemeasured as combinations of elastic torque S, viscous torque S”, storage shear modulus, G, loss shear modulus G”, tan ,complex dynamic viscosity *, and real dynamic viscosity .5. Significance and Use5.1 This test method is used
24、 to measure viscoelastic properties of thermoplastic elastomer polymer melts at elevatedtemperatures as well as the dynamic properties of the respective congealed thermoplastic elastomer specimens measured at lowertemperatures. These polymer melt viscoelastic properties may relate to factory process
25、ing behavior while the dynamic propertiesof the respective congealed specimen may relate to product performance.5.2 This test method may be used for quality control in thermoplastic elastomer manufacturing processes, for quality controlof received shipments of thermoplastic elastomers, and for resea
26、rch and development testing of thermoplastic elastomers. Thismethod may also be used for evaluating processing and product performance differences resulting from the use of differentcompounding materials and process conditions in the making of these thermoplastic elastomers.6. Apparatus6.1 Torsion S
27、train 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 cavity.6.2 Sealed Die CavityThe sealed die cavity is formed
28、by two parallel plate 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. The die gap for these parallel plate dies shallbe set at 2.58 6
29、 0.1 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 consists of a direct drive motor which imparts a tors
30、ional oscillatingmovement to the lower die in the cavity plane.6.5.1 The oscillation amplitude can be varied, but a selection of 60.5 arc (7.0 % shear strain) is preferred for frequency sweeptests. The oscillation frequency can be varied between 0.03 Hz and 30 Hz.6.6 Torque Measuring SystemThe torqu
31、e measuring system shall measure the resultant shear torque.6.6.1 The torque measuring device shall be rigidly coupled to one of the dies, any deformation between the die and device shallbe negligibly small, and the device shall generate a signal which is proportional to the torque. The total error
32、resulting from zeropoint error, sensitivity error, linearity, and repeatability errors shall not exceed 1 % of the selected measuring range.D7605 11 (2016)26.6.2 The torque recording device shall be used to record the signal from the torque measuring device and shall have a responsetime for full sca
33、le deflection of the torque scale of 1 s or less. The torque shall be recorded with an accuracy of 60.5 % of therange. Torque recording devices may include analog chart recorders, printers, plotters, or computers.6.6.3 A reference torque device is required to calibrate the torque measurement system.
34、 A torque standard may be used tocalibrate the torque measuring system at the selected angular displacement by clamping a steel torsion rod to the oscillating andthe torque measuring dies of the torsion shear rheometer (see Fig. 2). The reference values for angular displacement andcorresponding torq
35、ue shall be established by the manufacturer for each torque standard.6.7 Reference Test TemperatureThe standard reference test temperature for thermoplastic elastomer polymer melts depend onthe melt transition temperature of the specific class ofTPE being tested. For example, measurements of the rhe
36、ology of the polymermelts of thermoplastic vulcanizates based on EPDM rubber and polypropylene are commonly tested at 215C with dynamicproperty measurements of the congealed specimen performed at 60C. For styrenic blocked copolymer thermoplastic elastomers,measurements of the polymer melts are perfo
37、rmed at 200C with dynamic property measurements of the congealed specimenperformed at 60C. For thermoplastic vulcanizates based on polyacrylate rubber and nylon, measurements of the polymer meltsare performed at 250C with dynamic property measurements of the congealed specimen performed at 60C. Test
38、s may be carriedout at other temperatures if required. Temperatures should be selected, when practical, in accordance with Practice D1349.6.8 Temperature Control SystemThis system shall permit the reference temperature to be varied between 40C and 250C withan accuracy of 60.3C or better.6.8.1 The di
39、es shall heat to the set point temperature in 1.0 min or less from closure of the test cavity. Once the initial heatingup time has been completed, die temperature shall not vary by more than 60.3C for the remainder of a test at a set temperature.When the set temperature is changed in a programmed te
40、mperature sweep, rheological measurements should not be recorded untilthe 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
41、 test piece temperature shall not be exceeded.6.8.3 Die temperature 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 dietemperatu
42、re sensor.7. Test Specimen7.1 A test specimen taken from a sample shall be carefully cut to within 60.02 g of the target mass, which is equal to massrepresenting 105 % of the fill factor for the die cavity. The mass for 100 % fill factor can be empirically determined by testing aspecimen from the sa
43、mple that has a mass greater than the 100 % fill factor.After completing this test, the test specimen is carefullyremoved from the cavity, the film is carefully removed, and the flash is carefully cut away from this specimen. The sample isFIG. 1 Typical Sealed Torsion Shear Rotorless Rheometer with
44、Parallel Plate DiesD7605 11 (2016)3weighed to the nearest one hundredth of a gram. This weight is then multiplied by 1.05 to determine the target mass for all futuretests for this thermoplastic elastomer series of materials. Once a target mass for a desired TPE series (all with the same specificgrav
45、ity) has been established, all future specimen masses for this family of thermoplastic elastomers should be controlled to within60.02 g for best repeatability. The initial test specimen shape should fit well within the perimeter of the test cavity.7.2 Thermoplastic Elastomer SpecimensCondition the s
46、pecimen obtained in accordance with Practice D1349 until it hasreached room temperature (23 6 2.0C (73.4 6 3.6F) throughout. The thermoplastic elastomer test specimen should be testedas received, that is unmassed (not milled).7.2.1 Thermoplastic elastomer specimens in a sealed cavity oscillating rhe
47、ometer must be pre-conditioned in the instrumentbefore rheological measurements are made to improve test repeatability. A programmed pre-conditioning step shall consist ofoscillating the specimen at 0.5 Hz, 62.8 % strain, at the predetermined polymer melt temperature for the time interval of 0.5 min
48、.8. Procedure8.1 Select the frequency, strain, temperature and time for the conditioning step as listed for thermoplastic elastomer melt inTable 1.8.2 Select the frequency steps and the strain and temperature conditions for the frequency sweep for thermoplastic elastomermelt as listed in Table 1.8.3
49、 Select the strain steps and the frequency and temperature conditions for the strain sweep for the thermoplastic elastomer meltin Table 1.8.4 Select the strain steps and frequency and temperature conditions for the two “back to back” strain sweep for the congealedthermoplastic elastomer in Table 1.FIG. 2 Typical Torque Standard Calibration Device for Torsion Shear CuremetersD7605 11 (2016)48.5 Program a test configuration which incorporates all these conditions and store on the instrument computer opera
