ASTM E2602-09(2015)

Standard Test Methods for the Assignment of the Glass Transition Temperature by Modulated Temperature Differential Scanning Calorimetry

SIGNIFICANCE AND USE
5.1 Materials undergo an increase in molecular mobility at the glass transition seen as a sigmoidal step increase in the heat capacity. This mobility increase may lead to kinetic events such as enthalpic recovery, chemical reaction or crystallization at temperatures near the glass transition. The heat flow associated with the kinetic events may interfere with the determination of the glass transition.  
5.2 The glass transition is observed in differential scanning calorimetry as a sigmoidal or step change in specific heat capacity.  
5.3 MTDSC provides a test method for the separation of the heat flow due to heat capacity and that associated with kinetic events making it possible to determine the glass transition in the presence of interfering kinetic event.  
5.4 These test methods are useful in research and development, quality assurance and control and specification acceptance.  
5.5 Other methods for assigning the glass transition temperature include differential scanning calorimetry (Test Method E1356), thermomechanical analysis (Test Method E1545) and dynamic mechanical analysis (Test Method E1640).
SCOPE
1.1 These test methods describe the assignment of the glass transition temperature of materials using modulated temperature differential scanning calorimetry (MTDSC) over the temperature range from –120 to +600°C. The temperature range may be extended depending upon the instrumentation used.  
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 There are no ISO equivalents to this standard.  
1.4 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.

General Information

• Status: Historical
• Publication Date: 30-Apr-2015
• ICS: 17.200.10 - Heat. Calorimetry
• Technical Committee: E37 - Thermal Measurements
• Drafting Committee: E37.01 - Calorimetry and Mass Loss

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: E2602 − 09 (Reapproved 2015)
Standard Test Methods for
the Assignment of the Glass Transition Temperature by
Modulated Temperature Differential Scanning Calorimetry
This standard is issued under the fixed designation E2602; 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 (´) indicates an editorial change since the last revision or reapproval.
1. Scope E1640 Test Method for Assignment of the Glass Transition
Temperature By Dynamic Mechanical Analysis
1.1 These test methods describe the assignment of the glass
transition temperature of materials using modulated tempera-
3. Terminology
ture differential scanning calorimetry (MTDSC) over the
temperature range from –120 to +600°C. The temperature 3.1 Definitions—Specific technical terms found in these test
range may be extended depending upon the instrumentation
methods are defined in Terminologies E473 and E1142 includ-
used. ing differential scanning calorimetry, glass transition, glass
transition temperature, specific heat capacity, and thermal
1.2 The values stated in SI units are to be regarded as
curve.
standard. No other units of measurement are included in this
standard.
3.2 Definitions of Terms Specific to This Standard:
3.2.1 extrapolated end temperature (Te), n—the point of
1.3 There are no ISO equivalents to this standard.
intersection of the tangent drawn at the point of greatest slope
1.4 This standard does not purport to address all of the
(that is, the inflection point) in the transition region with the
safety concerns, if any, associated with its use. It is the
extrapolated baseline following the transition.
responsibility of the user of this standard to establish appro-
3.2.2 extrapolated onset temperature (Tf), n—the point of
priate safety and health practices and determine the applica-
intersection of the tangent drawn at the point of greatest slope
bility of regulatory limitations prior to use.
(that is, the inflection point) in the transition region with the
extrapolated baseline prior to the transition.
2. Referenced Documents
2 3.2.3 midpoint temperature (Tm), n—the point on the ther-
2.1 ASTM Standards:
mal curve corresponding to the average of the extrapolated
E473 Terminology Relating to Thermal Analysis and Rhe-
onset and extrapolated end temperatures.
ology
3.2.4 modulated, n—a prefix indicating that a parameter
E967 Test Method for Temperature Calibration of Differen-
changes in a periodic manner during the experiment.
tial Scanning Calorimeters and Differential Thermal Ana-
lyzers
3.2.5 modulated heat flow, n—the heat flow resulting from
E968 Practice for Heat Flow Calibration of Differential
an applied modulated temperature program.
Scanning Calorimeters
3.2.6 modulated temperature differential scanning calorim-
E1142 Terminology Relating to Thermophysical Properties
etry (MTDSC), n—a method of differential scanning calorim-
E1356 Test Method for Assignment of the Glass Transition
etry (DSC) that varies the temperature sinusoidally or with a
Temperatures by Differential Scanning Calorimetry
periodic step-and-hold or pulse program to the test specimen
E1545 Test Method for Assignment of the Glass Transition
over a traditional isothermal or temperature ramp program.
Temperature by Thermomechanical Analysis
Results from the experiment include reversing and nonrevers-
ing heat flow and specimen temperature.
3.2.7 nonreversing heat flow, n—the kinetic component of
These test methods are under the jurisdiction of ASTM Committee E37 on
the total heat flow. That is, the portion of the heat flow that
Thermal Measurements and is the direct responsibility of Subcommittee E37.01 on
responds to temperature and not to the temperature rate of
Calorimetry and Mass Loss.
Current edition approved May 1, 2015. Published May 2015. Originally
change.
approved in 2009. Last previous edition approved in 2009 as E2602 – 09. DOI:
3.2.8 reversing heat flow, n—the portion of the total heat
10.1520/E2602-09R15.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
flow that responds to the temperature rate of change.
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
3.2.9 total heat flow, n—the value of the modulated heat
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. flow averaged over one modulation period or impulse.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
E2602 − 09 (2015)
3.2.9.1 Discussion—The total heat flow is equivalent to the and reference equivalent to 1 µWand (4) a means of sustaining
heat flow signal of conventional differential scanning calorim- a test chamber environment of inert nitrogen (or other low
etry. conductivity) purge gas at a rate of 20 to 60 mL/min constant
3.2.9.2 Discussion—The total heat flow is equal to the sum to within 610 %.
of the reversing and nonreversing heat flows.
NOTE 1—The temperature range of interest depends upon the tempera-
ture of the glass transition. The apparatus need only address the tempera-
4. Summary of Test Method
tureregionfrom50°Cbelowto50°Cabovetheanticipatedglasstransition
temperature.
4.1 The determination of the glass transition by differential
scanning calorimetry using Test Method E1356 is difficult 6.1.2 A temperature controller, capable of executing a
when kinetic events such as the cure exotherm of a thermoset
specific temperature program by (1) operating the furnace
resin occur at or near the glass transition. In MTDSC, the total between selected temperature limits at a rate of temperature
heat flow signal is separated into reversing and nonreversing
change of 7 6 0.1°C/min, (2) holding at an isothermal
components. The heat capacity change that indicates the glass temperature within the temperature range of –120 to +600°C
transition appears in the reversing heat flow signal, while
within 60.1°C,and(3)forTestMethodA,varyingtemperature
kinetic events (for example, curing, enthalpy of recovery, etc.) sinusoidally with an amplitude of 60.9 to 1.1°C and a period
appear in the nonreversing heat flow signal. The separation of of 50 to 71 s (frequency of 14 to 20 mHz) or applying a
these two signals permits the determination of the enthalpy of 60.5°C pulse at intervals between 15 and 30 s.
reaction and the assignment of the glass transition in a single 6.1.3 A calculating device, capable of transforming the
experiment. experimentally determined modulated temperature and modu-
4.1.1 This MTDSC method involves the continuous moni- lated specimen heat flow signals into the required continuous
toring of the reversing and nonreversing heat flow into or out output forms of reversing and nonreversing heat flow and
ofatestspecimenasitisheatedatacontrolledratethroughthe average test temperature to the required accuracy and preci-
glass transition region.
sion.
6.1.4 A data collection device, to provide a means of
5. Significance and Use
acquiring, storing and displaying measured or calculated sig-
nalsorboth.TheminimumoutputsignalsrequiredforMTDSC
5.1 Materials undergo an increase in molecular mobility at
are heat flow, reversing heat flow, nonreversing heat flow,
the glass transition seen as a sigmoidal step increase in the heat
elapsed time and average specimen temperature signals.
capacity.Thismobilityincreasemayleadtokineticeventssuch
as enthalpic recovery, chemical reaction or crystallization at
6.2 A coolant system to provide cooling at rates of at least
temperatures near the glass transition.The heat flow associated
2°C/min.
with the kinetic events may interfere with the determination of
6.3 Inert nitrogen or other low conductivity purge gas
the glass transition.
flowingatarateof20to60mL/minconstanttowithin 610%.
5.2 The glass transition is observed in differential scanning
NOTE 2—Helium, a commonly used purge gas with high thermal
calorimetry as a sigmoidal or step change in specific heat conductivity, may result in reduced temperature range, precision and
accuracy. Follow the manufacturers recommendation when using helium.
capacity.
6.4 A balance with a range of at least 200 mg to weigh
5.3 MTDSC provides a test method for the separation of the
specimens or containers, or both to 60.01 mg.
heat flow due to heat capacity and that associated with kinetic
events making it possible to determine the glass transition in
6.5 A Sapphire disk calibration material,10to30mgfor
the presence of interfering kinetic event. heat capacity calibration.
5.4 These test methods are useful in research and
6.6 Indium metal of >99.99 % purity for temperature and
development, quality assurance and control and specification enthalpy calibration.
acceptance.
6.7 Containers (pans, crucibles, etc.) that are inert to the
5.5 Other methods for assigning the glass transition tem- specimen and are of suitable structural shape and integrity to
peratureincludedifferentialscanningcalorimetry(TestMethod
contain the specimen in accordance with the specific require-
E1356), thermomechanical analysis (Test Method E1545) and ments of these test methods.
dynamic mechanical analysis (Test Method E1640).
6.8 Ameans, tool or device to close, encapsulate or seal the
container of choice.
6. Apparatus
6.1 The instrumentation required to provide the capability
7. Calibration and Standardization
for these test methods includes a MTDSC composed of:
7.1 Calibrate the temperature signal from the MTDSC
6.1.1 A differential scanning calorimeter (DSC)
...

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. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: E2602 − 09 E2602 − 09 (Reapproved 2015)
Standard Test MethodMethods for
the Assignment of the Glass Transition Temperature by
Modulated Temperature Differential Scanning Calorimetry
This standard is issued under the fixed designation E2602; 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 (´) indicates an editorial change since the last revision or reapproval.
1. Scope
1.1 ThisThese test method describesmethods describe the assignment of the glass transition temperature of materials using
modulated temperature differential scanning calorimetry (MTDSC) over the temperature range from –120 to + 600 °C. +600°C.
The temperature range may be extended depending upon the instrumentation used.
1.2 The values stated in inch-poundSI units are to be regarded as standard. The values given in parentheses are mathematical
conversions to SI units that are provided for information only and are not considered No other units of measurement are included
in this standard.
1.3 There are no ISO equivalents to this standard.
1.4 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.
2. Referenced Documents
2.1 ASTM Standards:
E473 Terminology Relating to Thermal Analysis and Rheology
E967 Test Method for Temperature Calibration of Differential Scanning Calorimeters and Differential Thermal Analyzers
E968 Practice for Heat Flow Calibration of Differential Scanning Calorimeters
E1142 Terminology Relating to Thermophysical Properties
E1356 Test Method for Assignment of the Glass Transition Temperatures by Differential Scanning Calorimetry
E1545 Test Method for Assignment of the Glass Transition Temperature by Thermomechanical Analysis
E1640 Test Method for Assignment of the Glass Transition Temperature By Dynamic Mechanical Analysis
3. Terminology
3.1 Definitions—Specific technical terms found in thisthese test methodmethods are defined in Terminologies E473 and E1142
including differential scanning calorimetry, glass transition, glass transition temperature, specific heat capacity, and thermal
curve.
3.2 Definitions of Terms Specific to This Standard:
3.2.1 extrapolated end temperature (Te), n—the point of intersection of the tangent drawn at the point of greatest slope (i.e., (that
is, the inflection point) in the transition region with the extrapolated baseline following the transition.
3.2.2 extrapolated onset temperature (Tf), n—the point of intersection of the tangent drawn at the point of greatest slope (i.e.,
(that is, the inflection point) in the transition region with the extrapolated baseline prior to the transition.
3.2.3 midpoint temperature (Tm), n—the point on the thermal curve corresponding to the average of the extrapolated onset and
extrapolated end temperatures.
3.2.4 modulated , modulated, n—a prefix indicating that a parameter changes in a periodic manner during the experiment.
ThisThese test method ismethods are under the jurisdiction of ASTM Committee E37 on Thermal Measurements and is the direct responsibility of Subcommittee E37.01
on Calorimetry and Mass Loss.
Current edition approved April 15, 2009May 1, 2015. Published June 2009May 2015. Originally approved in 2009. Last previous edition approved in 2009 as E2602 –
09. DOI: 10.1520/E2602-09. 10.1520/E2602-09R15.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
E2602 − 09 (2015)
3.2.5 modulated heat flow, n—the heat flow resulting from an applied modulated temperature programprogram.
3.2.6 modulated temperature differential scanning calorimetry (MTDSC), n—a method of differential scanning calorimetry
(DSC) that varies the temperature sinusoidally or with a periodic step-and-hold or pulse program to the test specimen over a
traditional isothermal or temperature ramp program. Results from the experiment include reversing and nonreversing heat flow and
specimen temperature.
3.2.7 nonreversing heat flow, n—the kinetic component of the total heat flow. That is, the portion of the heat flow that responds
to temperature and not to the temperature rate of change.
3.2.8 reversing heat flow , flow, n—the portion of the total heat flow that responds to the temperature rate of change.
3.2.9 total heat flow, n— The the value of the modulated heat flow averaged over one modulation period or impulseimpulse.
NOTE 1—The total heat flow is equivalent to the heat flow signal of conventional differential scanning calorimetry.
3.2.9.1 Discussion—
The total heat flow is equivalent to the heat flow signal of conventional differential scanning calorimetry.
NOTE 2—The total heat flow is equal to the sum of the reversing and nonreversing heat flows.
3.2.9.2 Discussion—
The total heat flow is equal to the sum of the reversing and nonreversing heat flows.
4. Summary of Test Method
4.1 The determination of the glass transition by differential scanning calorimetry using standard Test Method E1356 is difficult
when kinetic events such as the cure exotherm of a thermoset resin occur at or near the glass transition. In modulated temperature
differential scanning calorimetry (MTDSC) MTDSC, the total heat flow signal is separated into reversing and nonreversing
components. The heat capacity change that indicates the glass transition appears in the reversing heat flow signal, while kinetic
events (e.g., (for example, curing, enthalpy of recovery, etc.) appear in the nonreversing heat flow signal. The separation of these
two signals permits the determination of the enthalpy of reaction and the assignment of the glass transition in a single experiment.
4.1.1 This MTDSC method involves the continuous monitoring of the reversing and nonreversing heat flow into or out of a
test specimen as it is heated at a controlled rate through the glass transition region.
5. Significance and Use
5.1 Materials undergo an increase in molecular mobility at the glass transition seen as a sigmoidal step increase in the heat
capacity. This mobility increase may lead to kinetic events such as enthalpic recovery, chemical reaction or crystallization at
temperatures near the glass transition. The heat flow associated with the kinetic events may interfere with the determination of the
glass transition.
5.2 The glass transition is observed in differential scanning calorimetry as a sigmoidal or step change in specific heat capacity.
5.3 MTDSC provides a test method for the separation of the heat flow due to heat capacity and that associated with kinetic
events making it possible to determine the glass transition in the presence of interfering kinetic event.
5.4 ThisThese test method ismethods are useful in research and development, quality assurance and control and specification
acceptance.
5.5 Other methods for assigning the glass transition temperature include differential scanning calorimetry (Test Method E1356),
thermomechanical analysis (Test Method E1545) and dynamic mechanical analysis (Test Method E1640)).
6. Apparatus
6.1 The instrumentation required to provide the capability for thisthese test methodmethods includes a Modulated Temperature
Differential Scanning Calorimeter MTDSC composed of:
6.1.1 A differential scanning calorimeter (DSC) test chamber of (1)(1) a furnace or furnaces to provide uniform controlled
heating or cooling of a specimen and reference to a constant temperature or at a constant rate within the range from –120 to +
600+600°C, (2 °C, (2) ) a temperature sensor to provide an indication of the specimen temperature readable to 6 0.0160.01°C,
(3 ° C, (3) ) a differential sensor to detect a heat flow difference between specimen and reference equivalent to 1 μW and (4)(4)
a means of sustaining a test chamber environment of inert nitrogen (or other low conductivity) purge gas at a rate of 20 to 60
mL/min constant to within 610 %.
NOTE 1—The temperature range of interest depends upon the temperature of the glass transition. The apparatus need only address the temperature
region from 50 °C 50°C below to 50 °C 50°C above the anticipated glass transition temperature.
E2602 − 09 (2015)
6.1.2 A temperature controller, capable of executing a specific temperature program by (1)(1) operating the furnace between
selected temperature limits at a rate of temperature change of 7 6 0.1 °C/min,0.1°C/min, (2 (2) ) holding at an isothermal
temperature within the temperature range of -120 to + 600 °C within 6 0.1 °C, and (3)–120 to +600°C within 60.1°C, and (3)
for method Test Method A, varying temperature sinusoidally with an amplitude of 6 0.9 to 1.1 °C 60.9 to 1.1°C and a period of
50 to 71 s (frequency of 14 to 20 mHz) or applying a 60.5 ° C 60.5°C pulse at intervals between 15 and 30 s.
6.1.3 A calculating device, capable of transforming the experimentally determined modulated temperature and modulated
specimen heat flow signals into the required continuous output forms of reversing and nonreversing heat flow and average test
temperature to the required accuracy and precision.
6.1.4 A data collection device, to provide a means of acquiring, storing and displaying measured or calculated signals or both.
The minimum output signals required for MTDSC are heat flow, reversing heat flow, nonreversing heat flow, elapsed time and
average specimen temperature signals.
6.2 A coolant system to provide cooling at rates of at least 2 °C/min.2°C/min.
6.3 Inert nitrogen or other low conductivity purge gas flowing at a rate of 20 to 60 mL/min constant to within 6 10 610 %.
NOTE 2—Helium, a commonly used purge gas with high thermal conduc
...