Dynamic mechanical analysis: Difference between revisions

Revision as of 06:13, 19 September 2019

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===Measuring glass transition temperature===

[[ImageFile:Temp2019-10-17 Sweep20 Chem53823 45-DMA Reference Measurements Linear Drive - Anton Paar RheoCompass™.jpgpng|alt=|thumb|325px325x325px|Figure 2. ATypical temperatureDMA sweepthermogram testof onan Polycarbonateamorphous thermoplastic (polycarbonate). Storage Modulus (E’) and Loss Modulus (E’’) againstand temperatureLoss wereFactor plotted. Differenttan(delta) initialare staticplotted loadas andfunction strainof were usedtemperature. The glass transition temperature of Polycarbonate was detected to be around 150 degree 151°C.The Polycarbonate(evaluation samplesaccording wereto madeISO from the material purchased from Mcmaster6721-Carr, #8574k2611)]]
One important application of DMA is measurement of the [[Glass transition#Transition temperature Tg|glass transition temperature]] of polymers. Amorphous polymers have different glass transition temperatures, above which the material will have [[rubber]]y properties instead of glassy behavior and the stiffness of the material will drop dramatically with an increase in viscosity. At the glass transition, the storage modulus decreases dramatically and the loss modulus reaches a maximum. Temperature-sweeping DMA is often used to characterize the glass transition temperature of a material.

===Polymer composition===