ASTM_E_2550_-_11.pdf

Designation:E255011Standard Test Method forThermal Stability by Thermogravimetry1This standard is issued under the fixed designation E2550;the number immediately following 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 covers the assessment of materialthermal stability through the determination of the temperatureat which the materials start to decompose or react and theextent of the mass change using thermogravimetry.The testmethod uses minimum quantities of material and is applicableover the temperature range from ambient to 800C.1.2 The absence of reaction or decomposition is used as anindication of thermal stability in this test method under theexperimental conditions used.1.3 This test method may be performed on solids or liquids,which do not sublime or vaporize in the temperature range ofinterest.1.4 This test method shall not be used by itself to establisha safe operating or storage temperature.It may be used inconjunction with other test methods(for example,E487,E537and E1981)as part of a hazard analysis of a material.1.5 This test method is normally applicable to reaction ordecomposition occurring in the range from room temperatureto 800 C.The temperature range may be extended dependingon the instrumentation used.1.6 This test method may be performed in an inert,areactive or self-generated atmosphere.1.7 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.8 There is no ISO standard equivalent to this test method.1.9 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.This standard mayinvolve hazardous materials,operations,and equipment.2.Referenced Documents2.1 ASTM Standards:2E473 Terminology Relating to Thermal Analysis and Rhe-ologyE487 Test Method for Constant-Temperature Stability ofChemical MaterialsE537 Test Method for The Thermal Stability of Chemicalsby Differential Scanning CalorimetryE691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test MethodE1142 Terminology Relating to Thermophysical PropertiesE1445 Terminology Relating to Hazard Potential of Chemi-calsE1582 Practice for Calibration of Temperature Scale forThermogravimetryE1981 Guide for Assessing Thermal Stability of Materialsby Methods of Accelerating Rate CalorimetryE2040 Test Method for Mass Scale Calibration of Thermo-gravimetric Analyzers3.Terminology3.1 Definitions:3.1.1 Specific technical terms used in this test method aredefined in Terminologies E473,E1142 and E1445.These termsinclude thermogravimetry(TG),thermogravimetric analysis(TGA),thermal stability,onset temperature(To),derivative,and TG curve.3.2 Definitions of Terms Specific to This Standard:3.2.1 DTG curve,na plot of the first derivative of TG datawith respect to temperature or time.3.2.2 mass change plateau,na region of the TG curvewith a relatively constant mass;it is accompanied by aminimum in the DTG curve for a mass loss,or a maximum fora mass gain.4.Summary of Test Method4.1 A sample of the material to be examined is placed in aninert container and then heated at a controlled rate of 1 to 20C1This test method is under the jurisdiction ofASTM Committee E37 on ThermalMeasurements and is the direct responsibility of Subcommittee E37.01 on Calo-rimetry and Mass Loss.Current edition approved April 1,2011.Published May 2011.Originallyapproved in 2007.Last previous edition approved in 2007 as E2550 07.DOI:10.1520/E2550-11.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 min1under a controlled atmosphere.The sample mass isrecorded continuously as a function of time and temperature.4.2 When the sample undergoes a reaction or thermaldecomposition involving a mass change,that change is indi-cated by a departure from the initially established baseline ofthe mass record(see Fig.1).4.3 The onset temperature and mass changes are determinedand reported.5.Significance and Use5.1 TG provides a rapid method for determining the thermaldecomposition and reaction mass change of a material.5.2 This test method is useful in detecting potentiallyhazardous reactions and in estimating the temperatures atwhich these reactions occur.This test method is recommendedas a screening test for detecting the thermal hazards of anuncharacterized mat