Measurement of glass transition temperature by mechanical (DMTA), thermal (DSC and MDSC), water diffusion and density methods: A comparison study

Glass transition measured by DMTA from the change in slope in storage modulus was 55 degrees C, which was 10.5 degrees C lower than the value measured by tan peak. Initial glass transition measured by DSC, increased exponentially and reached. a constant value of 55 degrees C at or higher heating rate of 30 degrees C/min. Transition temperature, measured by MDSC, remained constant up to heating rate 15 degrees C/min and then decreased. The glass transition values determined from reversible heat flow was 60 degrees C. The break in diffusivity and density (i.e. volume) was observed at 50 degrees C below the glass transition temperature measured by thermal and mechanical methods. (c) 2007 Elsevier B.V. All rights reserved.