Standard Test Method for Decomposition Kinetics by Thermogravimetry Using the Ozawa/Flynn/Wall Method

SIGNIFICANCE AND USE
5.1 Thermogravimetry provides a rapid method for determining the temperature-decomposition profile of a material.  
5.2 This test method can be used for estimating lifetimes of materials, using Test Method E1877 provided that a relationship has been established between the thermal endurance test results and actual lifetime tests.
SCOPE
1.1 This test method describes the determination of the kinetic parameters, Arrhenius activation energy, and preexponential factor by thermogravimetry, based on the assumption that the decomposition obeys first-order kineticsusing the Ozawa/Flynn/Wall isoconversional method (1, 2).2  
1.2 This test method is generally applicable to materials with well-defined decomposition profiles, namely, a smooth, continuous mass change with a single maximum rate.  
1.3 This test method is normally applicable to decomposition occurring in the range from 400 to 1300K (nominally 100 to 1000°C). The temperature range may be extended depending on the instrumentation used.  
1.4 This test method is similar to ISO 11358-2 but differs in its mathematical treatment.  
1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.  
1.6 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
28-Feb-2015
Current Stage
Ref Project

Relations

Buy Standard

Standard
ASTM E1641-15 - Standard Test Method for Decomposition Kinetics by Thermogravimetry Using the Ozawa/Flynn/Wall Method
English language
7 pages
sale 15% off
Preview
sale 15% off
Preview
Standard
REDLINE ASTM E1641-15 - Standard Test Method for Decomposition Kinetics by Thermogravimetry Using the Ozawa/Flynn/Wall Method
English language
7 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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: E1641 − 15
StandardTest Method for
Decomposition Kinetics by Thermogravimetry Using the
1
Ozawa/Flynn/Wall Method
This standard is issued under the fixed designation E1641; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope E691Practice for Conducting an Interlaboratory Study to
Determine the Precision of a Test Method
1.1 This test method describes the determination of the
E1142Terminology Relating to Thermophysical Properties
kinetic parameters, Arrhenius activation energy, and preexpo-
E1582Practice for Calibration of Temperature Scale for
nential factor by thermogravimetry, based on the assumption
Thermogravimetry
that the decomposition obeys first-order kineticsusing the
2 E1877Practice for Calculating Thermal Endurance of Ma-
Ozawa/Flynn/Wall isoconversional method (1, 2).
terials from Thermogravimetric Decomposition Data
1.2 This test method is generally applicable to materials
E1970PracticeforStatisticalTreatmentofThermoanalytical
with well-defined decomposition profiles, namely, a smooth,
Data
continuous mass change with a single maximum rate.
E2040Test Method for Mass Scale Calibration of Thermo-
1.3 This test method is normally applicable to decomposi- gravimetric Analyzers
4
tion occurring in the range from 400 to 1300K (nominally 100
2.2 Other Standard:
to1000°C).Thetemperaturerangemaybeextendeddepending
ISO11358-2 Plastics Thermogravimetry (TG) of Polymers
on the instrumentation used.
Part 2: Determination of Kinetic Parameters
1.4 This test method is similar to ISO11358-2 but differs in
3. Terminology
its mathematical treatment.
3.1 Definitions—Technical terms used in this test method
1.5 The values stated in SI units are to be regarded as
are defined in Terminologies E473 and E1142 and include
standard. No other units of measurement are included in this
activation energy, Celsius, failure, failure criterion, and ther-
standard.
mogravimetric analyzer.
1.6 This standard does not purport to address all of the
safety concerns, if any, associated with its use. It is the
4. Summary of Test Method
responsibility of the user of this standard to establish appro-
4.1 Thistestmethodisbaseduponthegeneralrateequation
priate safety and health practices and determine the applica-
that takes the form of:
bility of regulatory limitations prior to use.
dα⁄dT 5 A~1 2 α! exp@2 E ⁄RT#⁄β (1)
2. Referenced Documents
3 where:
2.1 ASTM Standards:
α = fraction reacted (dimensionless),
E29Practice for Using Significant Digits in Test Data to
-1
A = pre-exponential factor (min ),
Determine Conformance with Specifications
β = heating rate (K/min),
E473Terminology Relating to Thermal Analysis and Rhe-
E = activation energy (J/mol),
ology
R = gas constant (=8.316 J/(mol K)),
T = absolute temperature (K),
1
ThistestmethodisunderthejurisdictionofASTMCommitteeE37onThermal
exp = Euler’s number exponential, and
Measurements and is the direct responsibility of Subcommittee E37.01 on Calo-
dα/dT = rate of change of α with T.
rimetry and Mass Loss.
Current edition approved March 1, 2015. Published March 2015. Originally
4.2 Using the method of Ozawa, Flynn and Wall (1, 2), Eq
approved in 1994. Last previous edition approved in 2013 as E1641–13. DOI:
1 may be solved for activation energy:
10.1520/E1641-15.
2
Theboldfacenumbersinparenthesesrefertothelistofreferencesattheendof
E 5 ~R ⁄ b! ∆log@β#⁄∆~1⁄ T! (2)
this standard.
3
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
4
Standards volume information, refer to the standard’s Document Summary page on Available fromAmerican National Standards Institute (ANSI), 25 W. 43rd St.,
the ASTM website. 4th Floor, New York, NY 10036, http://www.ansi.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

---------------------- Page: 1 ----------------------
E1641 − 15
where: 4.7 For first order reactions (n51), the value of the pre-
exponential factor (A) may be determined using Eq 3(4).
E = the derivative of the Doyle approximation (3) with
values tabulated in Table 1.
a
A 5 2 β R ⁄ E ln @1 2 α# 10 (3)
~ !~ !
4.3 Using a point of constant conversion from a series of
where:
decomposition curves obtained at different heat rates,
a = the Doyle approximation value from Table 1.
∆log@β#⁄∆ 1 2 T is obtained by linear regression.
~ !
4.8 This test method consists of heating a series of four or
4.4 Assuming an initial value of b50.457, a first approxima-
more test specimens, taken from the original sample, each at a
...

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: E1641 − 13 E1641 − 15
Standard Test Method for
Decomposition Kinetics by Thermogravimetry Using the
1
Ozawa/Flynn/Wall Method
This standard is issued under the fixed designation E1641; 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 This test method describes the determination of the kinetic parameters, Arrhenius activation energy, and preexponential
factor by thermogravimetry, based on the assumption that the decomposition obeys first-order kineticsusing the Ozawa/Flynn/Wall
2
isoconversional method (1, 2).
1.2 This test method is generally applicable to materials with well-defined decomposition profiles, namely, a smooth, continuous
mass change with a single maximum rate.
1.3 This test method is normally applicable to decomposition occurring in the range from 400 to 1300K (nominally 100 to
1000°C). The temperature range may be extended depending on the instrumentation used.
1.4 This test method is similar to ISO 11358-2 but differs in its mathematical treatment.
1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.6 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
3
2.1 ASTM Standards:
E29 Practice for Using Significant Digits in Test Data to Determine Conformance with Specifications
E473 Terminology Relating to Thermal Analysis and Rheology
E691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method
E1142 Terminology Relating to Thermophysical Properties
E1582 Practice for Calibration of Temperature Scale for Thermogravimetry
E1877 Practice for Calculating Thermal Endurance of Materials from Thermogravimetric Decomposition Data
E1970 Practice for Statistical Treatment of Thermoanalytical Data
E2040 Test Method for Mass Scale Calibration of Thermogravimetric Analyzers
4
2.2 Other Standard:
ISO 11358-2 Plastics Thermogravimetry (TG) of Polymers Part 2: Determination of Kinetic Parameters
3. Terminology
3.1 Definitions—Technical terms used in this test method are defined in Terminologies E473 and E1142 and include activation
energy, Celsius, failure, failure criterion, and thermogravimetric analyzer.
4. Summary of Test Method
4.1 This test method is based upon the general rate equation that takes the form of:
dα⁄dT 5 A 1 2 α exp@2 E ⁄ R T#⁄β (1)
~ !
1
This test method is 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 Aug. 1, 2013March 1, 2015. Published September 2013March 2015. Originally approved in 1994. Last previous edition approved in 20122013
as E1641 – 07 (2012).E1641 – 13. DOI: 10.1520/E1641-13.10.1520/E1641-15.
2
The boldface numbers in parentheses refer to the list of references at the end of this standard.
3
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
4
Available from American National Standards Institute (ANSI), 25 W. 43rd St., 4th Floor, New York, NY 10036, http://www.ansi.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

---------------------- Page: 1 ----------------------
E1641 − 15
where:
α = fraction reacted (dimensionless),
-1
A = pre-exponential factor (min ),
β = heating rate (K/min),
E = activation energy (J/mol),
R = gas constant (=8.316 J/(mol K)),
T = absolute temperature (K),
exp = Euler’s number exponential, and
dα/dT = rate of change of α with T.
4.2 Using the method of Ozawa, Flynn and Wall (1, 2),Eq 1 may be solved for activation energy:
E 5 ~R ⁄ b! Δlog@β#⁄Δ~1 ⁄ T! (2)
where:
E = the derivative of the Doyle approximation (3) with values tabulated in Table 1.
4.3 Using a point of constant conversion from a series of decomposition curves obtained at different heat rates, Δlog β ⁄Δ 1
@ # ~
2 T! is obtained by li
...

Questions, Comments and Discussion

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