差热扫描分析仪培训教程(TA-DSC-trianing)

QserialsDSC

TrainingSchool

TAInstrumentsDSC:TerminologyAmorphousPhase-Theportionofmaterialwhosemoleculesarerandomlyorientedinspace.Liquidsandglassyorrubberysolids.Thermosetsandsomethermoplastics.CrystallinePhase-Theportionofmaterialwhosemoleculesareregularlyarrangedintowelldefinedstructuresconsistingofrepeatunits.Veryfewpolymersare100%crystalline.Semi-crystallinePolymers-Polymerswhosesolidphasesarepartiallyamorphousandpartiallycrystalline.Mostcommonthermoplasticsaresemi-crystalline.Melting-Theendothermictransitionuponheatingfromacrystallinesolidtotheliquidstate.Thisprocessisalsocalledfusion.Themeltisanothertermforthepolymerliquidphase.Crystallization-Theexothermictransitionuponcoolingfromliquidtocrystallinesolid.Crystallizationisafunctionoftimeandtemperature.ColdCrystallization-Theexothermictransitionuponheatingfromtheamorphousrubberystatetothecrystallinestate.Thisonlyoccursinsemi-crystallinepolymersthathavebeenquenched(veryrapidlycooledfromthemelt)intoahighlyamorphousstate.EnthalpyofMelting/Crystallization-Theheatenergyrequiredformeltingorreleaseduponcrystallization.ThisiscalculatedbyintegratingtheareaoftheDSCpeakonatimebasis.TAInstrumentsDSC’sDSC2010DSC2910DSC2920Q系列™DSCQ2000是顶级的带有多种可选配置的研究级DSCQ200是具有扩展功能的研究级DSCQ20是基本型DSCDSCQ20P&DSCQ2000withPressureCellDSC光量热附件SDTQ600SDTQ600

同步DSC-TGA:同时测量热流和重量变化信号DSC:典型DSC转变温度热流->放热玻璃化转变结晶熔化交联(固化)氧化或分解UnderstandingDSCSignalsHeatFlowRelativeHeatFlow:measuredbyallDSCsexceptTAQ2000.Theabsolutevalueofthesignalisnotrelevant,onlyabsolutechangesareused.AbsoluteHeatFlow:usedbyQ2000.DividingthesignalbythemeasuredheatingrateconvertstheheatflowsignalintoaheatcapacitysignalFromdesktop,double-clickonQSeriesExplorerIconQSeriesExplorershowsalltheinstrumentsattachedtoyoursystemSignalDisplayMethodSegmentsReal-TimePlotSummary,Procedures,&NotesRunsintheSequenceCalibrationQ200&Q2000Tzero™CalibrationCellConstantandTemperatureCalibrationQ20BaselineCalibrationCellConstantandTemperatureCalibrationCalibrationQ200&Q2000Tzero™CalibrationCellConstantandTemperatureCalibrationQ20BaselineCalibrationCellConstantandTemperatureCalibrationTobegincalibrationstartDSCCalibrationWizardSelectHeatflowsignal&typeofcoolerQ2000=T4PQ200=T4Q20=T1SelectwhichcalibrationtoperformTzeroCalibrationEnterparametersforfirstrun(emptycell)StartexperimentEnterweightofsapphiresamplesWhenruniscompleted,capacitance&resistanceareplottedandsavedEnterparametersforIndiumsampleAlwaysrunIndiumforCellConstantEntertemperaturesforIndiumrunStartexperimentDataisanalyzedautomaticallyCalibrationQ200&Q2000Tzero™CalibrationCellConstantandTemperatureCalibrationQ20BaselineCalibrationCellConstantandTemperatureCalibrationTobegincalibrationstartDSCCalibrationWizardSelecttypeofcalibrationtorunEnterparametersReviewsummaryEntersampleinformationFinishenteringsampleinformationReviewchecklistBaselinecalibrationrunningStartcalibrationanalysisFileisopenedautomaticallySelectlimitsthenclickonLimitsOkbuttonClickonAccepttosavecalibrationOncethefileisanalyzedandtheresultsaresaved,acheckmarkappearsnexttothefilenameTobegincalibrationstartDSCCalibrationWizardSelecttypeofcalibrationtorunEnterparametersReviewsummaryEntersampleinformationFinishenteringsampleinformationReviewchecklistStartcalibrationanalysisFileisopenedandanalyzedautomatically.Clickanalyzetochangelimits,oracceptTzero

HeatFlowEquationHeatFlowSensorModelHowdowecalculatethese?Besidesthethreetemperatures(Ts,Tr,T0);whatothervaluesdoweneedtocalculateHeatFlow?MeasuringtheC’s&R’sTzero™CalibrationcalculatestheC’s&R’sCalibrationisamisnomer,THISISNOTACALIBRATION,butratherameasurementoftheCapacitance(C)andResistance(R)ofeachDSCcellAfterdeterminationofthesevalues,theycanbeusedintheFourTermHeatFlowEquationshowedpreviouslyMeasuringtheC’s&R’sPreformedusingTzero™CalibrationWizardRunEmptyCellRunSapphireonbothSample&ReferencesideAfewwordsabouttheCsandRsThecurvesshouldbesmoothandcontinuous,withoutevidenceofnoiseorartifactsCapacitancevaluesshouldincreasewithtemperature(withadecreasingslope)Resistancevaluesshoulddecreasewithtemperature(alsowithadecreasingslope)Itisnotunusualfortheretobeadifferencebetweenthetwosides,althoughoftentheyareveryclosetoidenticalGoodTzero™CalibrationRunEnableandSelectDiagnosticSignalsCheckthisbox!EnableandSelectDiagnosticSignalsSelect1-8foranRCSorallofthemforanLNCSMoreonDiagnosticSignalslaterAdvancedTzero™TechnologyDuringtransitionsandMDSC®experiments,theheatingratesofthesamplepan,samplecalorimeter,referencepanandreferencecalorimetermaybeverydifferent.Samplepanshavethermalresistanceandheatcapacityandsampleandreferencepansrarelyhavethesamemass.AdvancedTzeroincludestheheatcapacityofthepansandtheheatingratedifferencesbetweenthesampleandreferencecalorimetersandpans.Peaksaretallerandsharper,hencebothresolutionandsensitivityaredramaticallyimproved.AdvancedTzero™Model

AdvancedTzeroisafurtherrefinementoftheTzeromodelandtakesthemeasurementuptothesamplepan,onestepclosertotheactualsample

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mAdvancedTzeromodelincludesthePansTzeromodelstheCalorimetersRpCpanRsQ1000Q100AdvancedTzero™ThepantypeMUSTmatchthepanthatyouareusingBesureandenterpanweightsCoolers RefrigeratedCoolingAccessory(RCS)

LiquidNitrogenCoolingAccessory(LNCS)

FinnedAirCoolingAccessory(FACS)

QuenchCoolingAccessory(QCA)CoolersCoolingdevicesitsonflange

Nickelcoolingrodstransfercoolingtofurnace/cellUsedtoselecttypeofcooler,andtospecifystatusbetweenrunsRCSTemperatureRange-90°Cto550°CRCSTemperatureRange-90°Cto550°CCellpurgeandbasepurgerequiredwhenRCSisrunningSecondarypurgeisoptional,butrecommendedwhenusinginhighlyhumidenvironmentsDryN2tocoolinggasportonbackofDSCRCSTemperatureRange-90°Cto550°CCellpurgeandbasepurgerequiredwhenRCSisrunningSecondarypurgeisoptional,butrecommendedwhenusinginhighlyhumidenvironmentsDryN2tocoolinggasportonbackofDSCEnsurethatcellremainsaboveambientusingunloadrangeandstandbytemperatureUnloadrangeisthetemperaturethatthecellwillgotoattheendofarunIfunloadtemperaturerangeisnotactive,cellcanbecontrolledbyusingstandbytemperatureLNCSTemperatureRange-180°Cto550°CLNCSTemperatureRange-180°Cto550°CCellpurgeandbasepurgerequiredwhenLNCSisrunningSecondarypurgeisoptional,butrecommendedwhenusinginhighlyhumidenvironmentsDryN2tocoolinggasportonbackofDSCEnsurethatcellremainsaboveambientusingunloadrangeandstandbytemperatureFACSTemperatureRangeAmbientto725°C

FACSTemperatureRangeAmbientto725°C

Dryairtocoolinggasport

Quenchcooleravailabletocooldownquickerbetweenruns(notforsub-ambientuse)QCATemperatureRange-180°Cto550°CCellpurgeandbasepurgerequiredwhenusingaQCATopicKeepingyourDSCcellcleanCalibrationSamplePreparationThermalMethodKeepingtheDSCCellCleanOneofthefirststepstoensuringgooddataistokeeptheDSCcellcleanHowdoDSCcellsgetdirty?DecomposingsamplesduringDSCrunsSamplesspillingoutofthepanTransferfrombottomofpantosensorHowdowekeepDSCcellsclean?DONOTDECOMPOSESAMPLESINTHEDSCCELL!!!RunTGAtodeterminethedecompositiontemperatureStaybelowthattemperature!MakesurebottomofpansstaycleanUselidsUsehermeticpansifnecessaryTGAGivesDecompositionTemperatureCleaningCellIfthecellgetsdirtyCleanw/brushBrushgentlybothsensorsandcellifnecessaryBecarefulwiththeTzero™thermocoupleBlowoutanyremainingparticlesBrushingtheSampleSensorHeatFlowCalibration(CellConstant)HeatFlowCalibrationofDifferentialScanningCalorimeters–ASTME-968EnthalpyCalibrationPerformedusingCalibrationWizardOneRunIndiummetalSampleWeight1-5mgPre-meltsamplethefirsttimeyourunitHeatingrateof10°C/minDependentuponpurgegasCellConstantThecellconstantiscalculatedastheratioofthetheoreticalheatoffusionofastandardmaterial,tothemeasuredheatoffusion

CellConstantshouldbe0.95-1.20inN2TemperatureCalibrationTemperatureCalibrationofDifferentialScanningCalorimeters–ASTME-967PerformedusingCalibrationWizardIndiumCellconstantrunalsoperformstemperaturecalibrationCandoupto5standardsPuremetalstypicallyused-In,Sn,Zn,PbWe’vefoundthatontheQseriesDSC’sonetemperaturecalibrationpointisallthatisusuallyneededSamplePans Typeofpandependson-SampleformVolatilizationTemperaturerangeUselightest,flattestpanpossibleAlwaysusereferencepanofthesametypeassamplepanStandardDSCPans(Crimped)Pan&lidweighs~23mg,bottomofpanisflatUsedforsolidnon-volatilesamplesAlwaysuselid(seeexceptions)LidimprovesthermalcontactKeepssamplefrommovingExceptionstousingalidRunningoxidativeexperimentRunningPCAexperimentStandardDSCPans(Crimped)Crimpedpansareavailablein:Aluminum -upto600°CCopper -upto725°C(inN2)Gold -upto725°C StandardPanswithoutlidsGraphite -upto725°C(inN2)Platinum -upto725°C HermeticPans(Sealed)Pan&Lidweigh~55mg,bottomofpanisnotasflatasstdpansUsedforliquidsamplesandsampleswithvolatilesAlwaysuselid(sameexceptionsasbefore)Aftersealingpans,shouldformdomeHermeticPans(Sealed)HermeticPansareavailablein:Aluminum–<600°C;<3atm(300kPagage)AlodinedAluminum-<600°C;<3atm

(300kPagage)(Foraqueoussamples)Gold–<725°C,<6atm(600kPagage)SpecializedSealedPansHighVolume-100µL;<250°C;600psig(4.1MPa)HighPressure-35µL;<300°C;1450psig(10MPa)Note:3atmisapproximately44psigItDoesMatterWhatPanyouuseMonohydratePharmaceuticalsampleSampleShapeKeepsamplethinCoverasmuchasthebottomofpanaspossibleSampleShapeCutsampletomakethin,don’tcrushIfpellet,cutcrosssectionSampleShapeCutsampletomakethin,don’tcrushIfpellet,cutcrosssectionIfpowder,spreadevenlyoverthebottomofthepanUsingSamplePressWhenusingcrimpedpans,don’tovercrimpBottomofpanshouldremainflataftercrimpingWhenusingHermeticpans,alittlemorepressureisneededHermeticpansaresealedbyformingacoldwieldontheAluminumpansCrimpedPansHermeticPansGoodBadSealedNotSealedSampleSizeLargersampleswillincreasesensitivity but…………….Largersampleswilldecreaseresolution

Goalistohaveheatflowof0.1-10mWgoingthroughatransitionSampleSizeSamplesizedependsonwhatyouaremeasuringIfrunninganextremelyreactivesample(likeanexplosive)runverysmallsamples(<1mg)Pureorganicmaterials,pharmaceuticals(1-5mg)Polymers-~10mgComposites–15-20mgPurgeGasPurgegasshouldalwaysbeusedduringD