ASTM E2402-05

Standard Test Method for Mass Loss and Residue Measurement Validation of Thermogravimetric Analyzers

SIGNIFICANCE AND USE
This method may be used to validate the performance of a specific TGA apparatus.
This method may be used to validate the performance of a specific method based upon a TGA mass loss or residue measurement.
This method may be used to determine the repeatability of a specific apparatus, operator or laboratory.
This method may be used for specification and regulatory compliance purposes.
SCOPE
1.1 This method provides procedures for validating mass loss and residue measurements by thermogravimetric analyzers (TGA) and analytical methods based upon the measurement of mass loss or residue content. Performance parameters determined include mass loss and residue repeatability (precision), detection limit, quantitation limit, linearity and bias.
1.2 Validation of apparatus performance and analytical methods is requested or required for quality initiatives or where results may be used for legal purposes.
1.3 SI units are the standard.
1.4 There is no ISO standard equivalent to this method.
1.5 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: 31-Dec-2004
• ICS: 19.020 - Test conditions and procedures in general
• ICS: 71.040.10 - Chemical laboratories. Laboratory equipment
• Technical Committee: E37 - Thermal Measurements
• Drafting Committee: E37.10 - Fundamental, Statistical and Mechanical Properties

Relations

• Replaced By: ASTM E2402-11 - Standard Test Method for Mass Loss and Residue Measurement Validation of Thermogravimetric Analyzers
• Effective Date: 01-Apr-2011
• Referred By: ASTM E473-23a - Standard Terminology Relating to Thermal Analysis and Rheology
• Effective Date: 01-Jan-2005

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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.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:E2402–05
Standard Test Method for
Mass Loss and Residue Measurement Validation of
Thermogravimetric Analyzers
This standard is issued under the fixed designation E2402; 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 2.2 Other Standard:
United States Food and Drug Administration, Q2B Valida-
1.1 This method provides procedures for validating mass
tion of Analytical Procedures: Methodology, 62 FR
lossandresiduemeasurementsbythermogravimetricanalyzers
27464, May 19, 1997
(TGA) and analytical methods based upon the measurement of
mass loss or residue content. Performance parameters deter-
3. Terminology
mined include mass loss and residue repeatability (precision),
3.1 Technical terms used in this standard are defined in
detection limit, quantitation limit, linearity and bias.
Practice E177 and in Terminologies E473, E1142, and E2161.
1.2 Validation of apparatus performance and analytical
3.2 Definitions of Terms Specific to This Standard:
methodsisrequestedorrequiredforqualityinitiativesorwhere
3.2.1 highly volatile matter—materials (such as moisture,
results may be used for legal purposes.
plasticizer, residual solvent, etc.) that boil at temperatures
1.3 SI units are the standard.
below 200 °C.
1.4 There is no ISO standard equivalent to this method.
3.2.2 medium volatile matter—materials (such as oil and
1.5 This standard does not purport to address all of the
polymer degradation products) that boil in the temperature
safety concerns, if any, associated with its use. It is the
range between 200 and 400 °C.
responsibility of the user of this standard to establish appro-
3.2.3 residue—material remaining (such as metal compo-
priate safety and health practices and determine the applica-
nents, filler content or inert reinforcing materials) after more
bility of regulatory limitations prior to use.
volatile components are vaporized.
2. Referenced Documents 3.2.4 mass loss plateau—a region of a thermogravimetric
curve with a relatively constant mass (that is, accompanied by
2.1 ASTM Standards:
a minima in the first derivative of mass with respect to time).
E177 Practice for Use of the Terms Precision and Bias in
ASTM Test Methods
4. Summary of Test Method
E473 Terminology Relating to Thermal Analysis and Rhe-
4.1 Mass is the primary dependent parameter and tempera-
ology
ture is the primary independent parameter measured by TGA.
E1142 Terminology Relating to Thermophysical Properties
4.2 Mass loss and residue measurements are validated by
E1582 Practice for Calibration of Temperature Scale for
their direct measurement using thermogravimetric apparatus
Thermogravimetry
over a specified temperature range using reference materials of
E1970 Practice for Statistical Treatment of Thermoanalyti-
known volatiles content as an analyte.
cal Data
4.3 Alternatively, validation of a TGA method based upon
E2040 Test Method for Mass Scale Calibration of Thermo-
mass loss and residue measurements may be performed using
gravimetric Analyzers
a specific test specimen as the analyte.
E2161 Terminology Relating to Performance Validation in
4.4 The mass loss of three or more specimens (nominally
Thermal Analysis
representing the maximum, midpoint and minimum of the
range of the test method) is measured at least in triplicate. A
ThistestmethodisunderthejurisdictionofASTMCommitteeE37onThermal
fourth blank specimen, containing no analyte, is also measured
Measurements and is the direct responsibility of Subcommittee E37.10 on Funda-
at least in triplicate.
mental, Statistical and Mechanical Properties.
Current edition approved Jan. 1, 2005. Published February 2005. DOI: 10.1520/
NOTE 1—Repeatability is determined by performing a sufficient num-
E2402-05.
2 ber of determinations to calculate statistically valid estimates of the
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. Available from FDA, 5600 Fishers Lane, Rockville, MD 20857.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
E2402–05
standard deviation or relative standard deviation of the measurements.
7.1.4 Containers (pans, crucibles, etc.) that are inert to the
specimen and that will remain gravimetrically stable up to
4.4.1 Mass loss and residue linearity and bias are deter-
450 °C.
mined from the best-fit straight-line correlation of the results
7.2 Graduated micropipettes with a capacity of 20 to 40 µL
from measurements of the three or more specimens.
measurable to within 6 1 µL.
4.4.2 Mass loss and residue detection limit and quantitation
limit are determined from the standard deviation of the blank
8. Reagents and Materials
specimen measurements.
8.1 Mass Loss Reference Materials, preferably certified for
4.4.3 Mass loss and residue repeatability are determined
mass loss covering a range of 2, 50, and 98 % mass loss over
from the repeatability measurements of the three or more
the temperature range of 25 to 200 °C.
analyte-containing specimens.
NOTE 3—Materials with other mass loss values may be used but shall
be reported.
5. Significance and Use
8.2 Nitrogen (or other inert purge gas) of 99.9+ % purity.
5.1 This method may be used to validate the performance of
a specific TGA apparatus.
9. Hazards
5.2 This method may be used to validate the performance of
a specific method based upon a TGA mass loss or residue
9.1 During the course of these experiments, organic vapors
measurement.
are evolved from the specimen and will exhaust from the
5.3 This method may be used to determine the repeatability
instrument.Aventilationsystemshallbeusedtoensurethatthe
of a specific apparatus, operator or laboratory. operator is not exposed to these vapors.
5.4 This method may be used for specification and regula- 9.2 Review the Material Safety Data Sheets (MSDS) for the
tory compliance purposes. components of the Mass Loss Reference Materials for addi-
tional safety information.
6. Interferences
10. Calibration and Standardization
6.1 This method depends upon distinctive thermal stability
10.1 After turning the power on, allow the instrument to
ranges of the measured components as a principle of the test.
equilibrate for at least one hour prior to any measurement.
For this reason, impurities or other materials that have no
10.2 Perform any cleaning and calibration procedures de-
well-defined thermally stable range, or the thermal stability of
scribed by the manufacturer in the apparatus Operator’s
which are the same as other components, may create interfer-
Manual.
ences.
10.3 If not previously established, perform temperature and
mass calibrations according to Practices E1582 and E2040,
7. Apparatus
respectively, using the same purge gas, purge flow rate and
7.1 Thermogravimetric Analyzer (TGA)—The essential in-
heating rate (here 10 °C/min) to be used for validation experi-
strumentation required to provide minimum thermogravimetry
ments.
capability for this method includes:
7.1.1 A thermobalance composed of:
11. Procedure for Determining Mass Loss and Residue
7.1.1.1 Afurnace to provide uniform controlled heating of a
Measurement Repeatability, Detection Limit,
specimen to a constant temperature of 400 °C and at a constant
Quantitation Limit, Linearity and Bias
rate between 5 and 25 °C/min.
11.1 This process involves characterizing, in triplicate,
7.1.1.2 Atemperature sensor to provide an indication of the
specimens with no mass loss and at least three or more test
specimen/furnace temperature to 6 0.1 °C.
specimens taken to represent the low, medium and high
7.1.1.3 A continuous recording balance with a minimum
extremes of the range over which performance is to be
capacity of 100 mg and a sensitivity of 6 10 µg to measure the
validated.
specimen mass.
NOTE 4—The details of this procedure are written using mass loss
7.1.1.4 A means of maintaining the specimen/container
reference materials as an analyte, and with a generic set of experimental
under a controlled atmosphere using an inert gas of 99.9+ %
conditions.Forvalidationofaspecificmasslossmethod,specimensofthe
purity at a purge rate of 50 to 100 6 5 mL/min.
analyte should be prepared to represent the range of the intended test
method, and steps 11.2 to 11.20 replaced with the specific mass loss
NOTE 2—Excessive purge rates should be avoided as they may intro-
procedure (that is, sample size, heating rate, purge gas, purge flow rate,
duce interferences due to turbulence effects and temperature gradients.
etc.).
7.1.2 A temperature controller capable of executing a spe-
11.2 Prepare at least 150 mg quantities of each of the
cific temperature program by operating the furnace between
reference specimens covering the mass loss range of the test.
selected temperature limits at a rate of temperature change of
Nominal mass values might be 2, 50, and 98 mass loss %.
5 to 25 °C/min to within 6 0.5 °C/min.
NOTE 5—Most thermoanalytical methods cover 1.5 to 2 decades of
7.1.3 A recording device capable of recording and display-
range.Themassvaluesselectedshouldapproximatetheanticipatedrange.
ing any fraction of the specimen mass signal (TGA curve)
Other masses losses and mass ranges may be used but shall be reported.
including the signal noise as a function of any fraction of
temperature in
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