Standard Test Method for Plastics: Dynamic Mechanical Properties: Melt Rheology

SCOPE
1.1 This test method covers the use of dynamic mechanical instrumentation for use in gathering and reporting the rheological properties of thermoplastic resins. It may be used as a test method for determining the complex viscosity and significant viscoelastic characteristics of such materials as a function of frequency, strain amplitude, temperature, and time. Such properties may be influenced by fillers and other additives.
1.2 It incorporates a laboratory test method for determining the relevant rheological properties of a polymer melt subjected to various oscillatory deformations on an instrument of the type commonly referred to as mechanical or dynamic spectrometer.
1.3 This test method is intended to provide means of determining the rheological properties of molten polymers, such as thermoplastics and thermoplastic elastomers over a range of temperatures by nonresonant forced-vibration techniques. Plots of modulus, viscosity, and tan delta as a function of dynamic oscillation (frequency), strain amplitude, temperature, and time are indicative of the viscoelastic properties of a molten polymer.
1.4 This test method is valid for a wide range of frequencies, typically from 0.01 to 100 Hz.
1.5 This test method is intended for homogenous and heterogenous molten polymeric systems and composite formulations containing chemical additives, including fillers, reinforcements, stabilizers, plasticizers, flame retardants, impact modifiers, processing aids, and other important chemical additives often incorporated into a polymeric system for specific functional properties, and which could affect the processability and functional performance. These polymeric material systems have molten viscosities less than 10 6  Pa·s (107  poise).
1.6 Apparent discrepancies may arise in results obtained under differing experimental conditions. Without changing the observed data, reporting in full (as described in this test method) the conditions under which the data were obtained will enable apparent differences observed in another study to be reconciled.
1.7 Test data obtained by this test method are relevant and appropriate for use in engineering design.
1.8 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.
1.9 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
Note 1—This test method is technically equivalent to ISO 6721, Part 10.

General Information

Status
Historical
Publication Date
09-Sep-2001
Technical Committee
Current Stage
Ref Project

Relations

Buy Standard

Standard
ASTM D4440-95a - Standard Test Method for Plastics: Dynamic Mechanical Properties: Melt Rheology
English language
4 pages
sale 15% off
Preview
sale 15% off
Preview

Standards Content (Sample)


NOTICE: This standard has either been superseded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
Designation: D 4440 – 95a An American National Standard
Standard Practice for
Rheological Measurement of Polymer Melts Using Dynamic
Mechanical Procedures
This standard is issued under the fixed designation D 4440; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
1. Scope 1.7 Test data obtained by this practice is relevant and
appropriate for use in engineering design.
1.1 This practice covers the use of dynamic mechanical
1.8 The values stated in SI units are to be regarded as the
instrumentation for use in gathering and reporting the rheo-
standard. The values given in parentheses are for information
logical properties of thermoplastic resins. It may be used as a
only.
practice for determining the complex viscosity and significant
1.9 This standard does not purport to address all of the
viscoelastic characteristics of such materials as a function of
safety concerns, if any, associated with its use. It is the
frequency, strain amplitude, temperature, and time. Such prop-
responsibility of the user of this standard to establish appro-
erties may be influenced by fillers and other additives.
priate safety and health practices and determine the applica-
1.2 It incorporates a laboratory practice for determining the
bility of regulatory limitations prior to use.
relevant rheological properties of a polymer melt subjected to
various oscillatory deformations on an instrument of the type
2. Referenced Documents
commonly referred to as mechanical or dynamic spectrometer.
2.1 ASTM Standards:
1.3 This practice is intended to provide means of determin-
D 4000 Classification System for Specifying Plastic Mate-
ing the rheological properties of molten polymers, such as
rials
thermoplastics and thermoplastic elastomers over a range of
D 4065 Practice for Determining and Reporting Dynamic
temperatures by nonresonant forced-vibration techniques. Plots
Mechanical Properties of Plastics
of modulus, viscosity, and tan delta as a function of dynamic
D 4092 Terminology Relating to Dynamic Mechanical
oscillation (frequency), strain amplitude, temperature, and time
Measurements on Plastics
are indicative of the viscoelastic properties of a molten
polymer.
3. Terminology
1.4 This practice is valid for a wide range of frequencies,
3.1 Definitions: Definitions are in accordance with Termi-
typically from 0.01 to 100 Hz.
nology D 4092.
1.5 This practice is intended for homogenous and heterog-
enous molten polymeric systems and composite formulations
4. Summary of Practice
containing chemical additives, including fillers, reinforce-
4.1 A known amount of thermoplastic resin (molten powder
ments, stabilizers, plasticizers, flame retardants, impact modi-
or pellet, or solid preform disk) is placed in mechanical
fiers, processing aids, and other important chemical additives
oscillation at a fixed or varying frequency at isothermal
often incorporated into a polymeric system for specific func-
conditions or over a linear temperature increase or a time-
tional properties, and which could affect the processability and
temperature relation simulating a processing condition. Storage
functional performance. These polymeric material systems
(elastic) G8 or loss (viscous) moduli, G88, or both, or the
6 7
have molten viscosities less than 10 Pa·s (10 poise).
corresponding dynamic viscosity functions n8 =g88/w and
1.6 Apparent discrepancies may arise in results obtained
n88=g8/w, of the polymeric material specimen are measured in
under differing experimental conditions. Without changing the
shear as a function of frequency, strain, temperature, or time.
observed data, reporting in full (as described in this practice)
the conditions under which the data were obtained will enable
5. Significance and Use
apparent differences observed in another study to be recon-
5.1 This practice provides a simple means of characterizing
ciled.
the important rheological properties and viscosity of thermo-
plastic resins using very small amounts of material (approxi-
mately 25 to 50 mm in diameter by 1 to 3 mm in thickness .
This practice is under the jurisdiction of ASTM Committee D-20 on Plastics
and is the direct responsibility of Subcommittee D20.10 on Mechanical Properties.
approximately 3 to 5 g). Data may be used for quality control,
Current edition approved Oct. 10, 1995. Published December 1995. Originally
research and development, and establishment of optimum
published as D 4440 – 84. Last previous edition D 4440 – 95.
Dynamic Mechanical Instrumentation is available from Rheometrics, Inc.,
Piscataway, NJ 08854 and The Perkin-Elmer Corp., 761 Main Avenue, Norwalk, CT
06859-0256, (203) 762-1000. Annual Book of ASTM Standards, Vol 08.02.
Copyright © ASTM, 100 Barr Harbor Drive, West Conshohocken, PA 19428-2959, United States.
D 4440
processing conditions. force (stress or strain), frequency, and temperature. Tempera-
5.2 Dynamic mechanical testing provides a sensitive ture should be measurable with a precision of 61°C, frequency
method for determining molten polymer properties by measur- to 61 %, and force to 61%.
ing the elastic and loss moduli as a function of frequency, 7.2.4 Temperature Controller and Oven—A device for con-
strain, temperature, or time. Plots of viscosity, storage, and loss trolling the specimen temperature, either by heating (in steps or
moduli, and tan delta as a function of the aforementioned ramps), cooling (in steps or ramps), or maintaining a constant
process parameters provide graphical representation indicative specimen environment, or a combination thereof. Fig. 1 illus-
of molecular weight, molecular weight distribution, effects of trates several time-temperature profiles. A temperature pro-
chain branching, and melt-processability for specified condi- grammer should be sufficiently stable to permit measurement
tions. of sample temperature to 1°C.
5.3 Values obtained in this practice can be used to assess the 7.3 Nitrogen, or other gas supply for purging purposes.
following:
8. Test Specimens
5.3.1 Complex viscosity of the polymer melt as a function
of dynamic oscillation,
8.1 The molten polymer composition should be both homo-
5.3.2 Processing viscosity, minimum as well as changes in geneous and representative.
viscosity as a function of experimental parameters, 8.2 Due to various geometries that might be used for
5.3.3 Effects of processing treatment, dynamic mechanical characterization of molten polymeric
5.3.4 Relative resin behavioral properties, including viscos- systems, size is not fixed by this practice; however, sample
ity and damping, and geometry (diameter and thickness) should be reported for any
5.3.5 Effects of formulation additives that might affect series of comparisons.
processability or performance.
8.3 Serrated tooling might be used for materials exhibiting
5.4 For many materials, there may be a specification that interfacial slippage due to high modulus.
requires the use of this practice, but with some procedural
9. Calibration
modifications that take precedence when adhering to the
specification. Therefore, it is advisable to refer to that material
9.1 Calibrate the instrument using procedures recommended
specification before using this practice. Table 1 of Classifica-
by the manufacturer.
tion System D 4000 lists the ASTM materials standards that
10. Procedure
currently exist.
10.1 Lower the upper test fixture so that it is touc
...

Questions, Comments and Discussion

Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.