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LogoAddYourCompanySloganSynchronousThermalAnalyzer同步热分析仪（STA）1IntroductionContents1Principle2Structure3Operation&Maintenance4Application52Introduction•ThermalAnalysis(TA)STAisbasedonthermalanalysis•1915Japan本多光太郎thermo-balance（热天平）•Recentyearscontrolledbycomputer、highautomationandmoreprecise•CombinationwithotherinstrumentsTG-MS、TG-GC、TG-FTIRetc.3Introduction•MassThermogravimetry(TG)DifferentialThermogravimetry(DTG)•TemperatureHeating-curveDetermination(HCD)DifferentialThermalAnalysis(DTA)•EnthalpyDifferentialScanningCalorimetry(DCS)4Principle•TGAtacertaintemperature,theweightofthematerialwillchangebecausesomeingredientsofthesubstancewillbedecomposedorremoved.TGisusedtomeasuretherelationshipbetweentheweightofmaterialandtemperaturechangesunderprogram-controlledtemperaturechange.Thermogravimetriccurveisrecorded,qualityastheordinateandtemperatureasabscissa.m=f(T或t)•DTGDifferentialthermogravimetriccurve(DTGcurve)isobtainedbydifferentialprocessingofTGcurve.dm/dt=f(T或t)5•ThermalbalanceThermalbalanceisthemostimportantpartoftheSTAinstrument.Theprincipleofthermalbalanceissimilarwithwhichofbalance.Itcanmeasuretheweighofsamplecontinuouslyintheconditionofheatingandrecordtherelationshipbetweenchangesofsampleweightandtemperaturecontinuously.Principle6StructureSTA同步热分析仪HeatingfurnaceControlsystemoftemperatureThermalbalanceMassflowmeterSignaldetectionandrecordsystem7OperationWeighingsamplesProgram1Specialcrucible210±0.1mg3ZerosampleWeighsample1Initialstate2Purgegas3TemperatureprogramwithgasswitchOnandOFF1Turnon/Offallinstruments2Open/Closethegascylinder3Connect/Disconnectthecomputer8attention•Maintenance1.Useethanoloracetonetowipetheinsidesurfaceofthefurnace.2.Runtheheatingprogramto900℃withnosampleanduseairasthepurgegas.3.Washthecylindersusingultrasoniccleaner,theheatthemat900℃.4.Replacetheglasscottonpiece.No.1Keeptheoutersurfaceofthecrucibleclean.No.2Don’tsprinklethesampleontheoutside.No.3Don’tturnofftheinstrumentwhenthesampletemperatureishigherthan100℃.No.4etc.Maintenance9ApplicationTG1.Processandmechanismofthermaldecompositionreaction.2.Crystalwater,absorbedwaterandwaterremoval.3.Reactionsbetweensolidandgas.4.Analysisofcompositionofsubstances.Andsoon.DTGThedifferencebetweenTGandDTGisthatsignalsarehandleddifferently.DTGcurveispeakycurveandthepointatthepeakmaximumiscorrespondingtotheinflectionpointofTGcurve.Therateofthereaction.10Questions&answers•1.使用这台仪器时是否需要参比物？答：不需要。仪器中只有一个天平，只需将样品放入其中即可。•2.升温速率范围是多少，不同升温速率对TG有什么影响？答：升温速率5-100℃/min。不同的升温速率对样品的传热有影响，升温速率越快，样品温度与设定温度之间的延迟越大，在某一温度段的停留时间越短。通常升温速率在10-30℃/min比较合适。•3.这台仪器可否测热量变化，与DSC的区别是什么？答：可以，在数据中选择热量即可。数据与DSC基本相同，可以得到物质的吸、放热数据。•4.热重谱图如何分析？答：热重谱图应包括TG、DTG和热量曲线。TG曲线是阶梯式的，应按阶段分析；DTG曲线是峰形曲线，可以观察最大峰值；热量曲线可以分析样品的吸、放热性质。这三条曲线应该配合起来一起分析。11LogoAddYourCompanySloganThankyouforyourattention!12