I got the following DSC curve for a polymer. I am seeking help from researchers, how to find Tg, Tm, Tc, % crystallization & Heat of fusion for this curve.
@JOHAN J. SANCHEZ
1. Thermoplastic, amorphous polymer
2. Sample Mass=2mg
3. Heating
4. Method: Ramp
5. Equipment: DSC Q20 V24.4 Build 116 (Universal V4.5A TA Instruments)
Dear K.R.
the thermogram you recorded is of very low quality (artefacts?) and I would not spend too much time in interpreting this curve. Run the sample again and care for a clean oven and improve the thermal signal.
Sample preparation: increase the sample mass to get a better signal but care for a good contact between sample and the bottom of the sample pan.
Increase the heating rate - this increases the thermal signal. 20 K/min should not be a problem with this instrument. Try different heating rates.
Care for better balance in the system (slope is bad). The reference pan should be of very similar mass as the sample pan.
Start your curve with a isothermal step or go to the starting temperature before starting the run to minimize the transient process.
Run subsequent heating and cooling sequences (keep cooling rates low to stay under controll).
The upper temperature of 375 °C is rather high and you may thermally decompose your polymer. If you have an amorphous polymer you should mainly see the glass transition and you cannot measure a melting reaction. The glass transition occurs in the lower temperature range and you need not to exceed 200 °C.
Good luck
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