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Thermogravimetric Analysis (TGA). Chris Howell 08/06/10. Why TGA. Measures changes in weight as a function of T Measure degradation limits of sample Polymer degradation Moisture (solvent) content Polymeric Coatings Filler Content Kinetics Can be coupled to FTIR/Mass Spec.
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Thermogravimetric Analysis (TGA) Chris Howell 08/06/10
Why TGA • Measures changes in weight as a function of T • Measure degradation limits of sample • Polymer degradation • Moisture (solvent) content • Polymeric Coatings • Filler Content • Kinetics • Can be coupled to FTIR/Mass Spec
Principle of Operation • Machine is calibrated to Curie Point using known standards. (Alumel, Nickel, Perkalloy) • Temperature range 25-1000°C • Sensitivity – 1μg • Heat sample at constant rate (0.3 – 300°C/min) • Measure weight continually • Variation of atmosphere (N2, O2, air) • Plot integral % or differential mass loss
Machines • H-floor – fitted with carousel - (Speak to Mel H) • D42 - Armes group – fitted with carousel
Step by Step guide • Prep sample (vac dry if necessary) • Use a blow torch to clean a crucible in furnace • Leave to cool shortly • Load crucible into carousel • Follow explicit instructions written (A4 sheet next to machine) • Load crucible with 20-30 mg of sample • Unload crucible and blow torch in furnace
Explicit instructions • Turn on both nitrogen tanks • Switch on comp; user: administrator, no password • Open Pyris Manager & choose TGA • Click on the CD icon to open he player manager • >File>New Player • >Edit Playlist • >Add a Step>Select Sample Group • >Select line 1.1 on the list>Browse button to select on method and edit method • After modifying click the save button and close • >Add sample • >Insert sample ID and choose destination folder • >Tick Weight sample @ start of run box • >Add extra samples • Resume loading carousel with clean empty samples into the carousel • Once tare is complete load pans with and brush pans after • Click the play button to run = DONE