Quasi-isothermal analysis

Figure 1 Quasi-isothermal analysis of the glass transition of poly(ethylene tetephttialate).

Quasi-isothermal Analysis of the Glass Transition of Poly(ethylene Terephthalate)... 

The next five figures show experimental results on the melting of pentacontane, C50H1Q2, a paraffin which melts practically reversibly [3]. Figure A.13.11 illustrates the comparison of a standard DSC trace and a quasi-isothermal analysis with a... 

Tft)> — T t) is identical to the result expected from a quasi-isothermal experiment = 0, see Section 3.3) and is called pseudo-isothermal. The quasi-isothermal analysis has been described in detail and yields for the heat capacity the following expression which also holds for the pseudo-isothermal case [31] where is the modulation amplitude of AT which is proportional to the heat-flow rate, HF (A oc Ahf) -... 

Figure 4.58. Quasi-isothermal analysis of the glass transition of amorphous PET. Data as shown in the glass transition region of Figure 4.51. [A] Normalisation to the ACp of Figure 4.51. [B] Conversion as suggested by Eq. (22).

Figure 4.79. Reversing heat flow rate and Lissajous figure of the quasi-isothermal analysis at...

Modulated temperature DSC has also been used to study plasticization of poly(ethylene terephthalate) by water. PET is somewhat hygroscopic and absorbs moisture, so the glass transition temperature will decrease. Quasi-isothermal analysis was used and the glass transition temperature was found to increase with time as the water evaporated (Toda et al. 1997d). A similar analysis was performed to investigate the effects of water on Nylon 6. A hermetically sealed pan was used and the plasticized glass transition separated into the reversing heat flow (TA Instruments 1994). 

QIA Quasi-isothermal analysis RS Raman scattering/spectroscopy... 

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