ASTM_E_2041_-_13e1.pdf

Designation:E2041131Standard Test Method forEstimating Kinetic Parameters by Differential ScanningCalorimeter Using the Borchardt and Daniels Method1This standard is issued under the fixed designation E2041;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.1NOTEWarning statements were editorially corrected throughout in September 2013.1.Scope1.1 This test method describes the determination of thekinetic parameters of activation energy,Arrhenius pre-exponential factor,and reaction order using the Borchardt andDaniels2treatment of data obtained by differential scanningcalorimetry.This test method is applicable to the temperaturerange from 170 to 870 K(100 to 600C).1.2 This treatment is applicable only to smooth exothermicreactions with no shoulders,discontinuous changes,or shifts inbaseline.It is applicable only to reactions with reaction ordern 2.It is not applicable to acceleratory reactions and,therefore,is not applicable to the determination of kineticparameters for most thermoset curing reactions or to crystalli-zation reactions.1.3The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.4 This test method is similar,but not equivalent to,ISO 11357,Part 5,that contains provisions for additionalinformation not supplied by this test method.1.5 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.2.Referenced Documents2.1 ASTM Standards:3E473 Terminology Relating to Thermal Analysis and Rhe-ologyE537 Test Method for The Thermal Stability of Chemicalsby Differential Scanning CalorimetryE698 Test Method for Arrhenius Kinetic Constants forThermally Unstable Materials Using Differential Scan-ning Calorimetry and the Flynn/Wall/Ozawa MethodE967 Test Method for Temperature Calibration of Differen-tial Scanning Calorimeters and Differential Thermal Ana-lyzersE968 Practice for Heat Flow Calibration of DifferentialScanning CalorimetersE1142 Terminology Relating to Thermophysical PropertiesE1445 Terminology Relating to Hazard Potential of Chemi-calsE1641 Test Method for Decomposition Kinetics by Thermo-gravimetry Using the Ozawa/Flynn/Wall MethodE1970 Practice for Statistical Treatment of ThermoanalyticalData2.2 ISO Standards:4ISO 11357 Part 5:Determination of Temperature and/orTime of Reaction and Reaction Kinetics3.Terminology3.1 DefinitionsSpecific technical terms used in this testmethod are defined in Terminologies E473,E1142,and E1445,including calibration,calorimeter,differential scanningcalorimetry,enthalpy,peak,reaction,repeatability,reproducibility,and slope.4.Summary of Test Method4.1 A test specimen is heated at a linear rate in a differentialscanning calorimeter or other suitable calorimeter through aregion of exothermic reaction behavior.The rate of heatevolution,developed by a chemical reaction,is proportional tothe rate of reaction.Integration of the heat flow as a function oftime yields the total heat of a reaction.1This test method is under the jurisdiction ofASTM Committee E37 on ThermalMeasurements and the direct responsibility of Subcommittee E37.01 on Calorimetryand Mass Loss.Current edition approved Sept.15,2013.Published September 2013.Originallyapproved in 1999.Last previous edition approved in 2008 as E2041 081.DOI:10.1520/E2041-13E01.2Borchardt,H.J.,Daniels,F.,Journal of the American Chemical Society,Vol 79,1957,pp.4146.3For 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.4Available 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 States1 4.2 The Borchardt and Daniels2data treatment is used toderive the kinetic parameters of activation energy,Arrheniuspre-exponential factor,and reaction order from the heat flowand total heat of reaction information obtained in 4.1(seeSection 5).5.Basis of Methodology5.1 Kinetic reactions may be modeled with a number ofsuitable equations.The Borchardt and Daniels2method makesuse of the rate equation to describe the dependence of the rateof reaction on the amount of material present.d/dt5 kT!1 2!n(1)where:d/dt=reaction rate(min1)=fraction reacted(dimensionless),k(T)=rate constant at temperature T(min1),andn=reaction order(dimensionless).5.2 For a reaction conducted at temperature(T),the rateequation o