I did dsc analysis for my drug and drug-polymer mixture, and seeking to learn about interpretation.
Mirek listed very correctly what you could determine by a DSC measurement. Summarize, all the transformations which are carried by enthalpy changes and all the parameters which can be determined from these measured enthalpy data, e.g. kinetical or thermodynamical parameters of the processes carried by heat change.
In practical view of point, for example, DSC can be used to find phase transformation temperatures (e.g. to find new crystalline modifications of pharmaceutically active compounds, because of patenting), determine the hysteresis of the processes carrying with heat change (melting, glass forming, phase transition, decomposition, crystallization, etc. )
You can determine basic material characteristics, structural transformations, thermooxidative behaviour and stability, crystallinity, water state in materials etc. Tg, Tm, Tcc etc.
Also, you can determine, in most cases, the mechanism of reaction by fitting the DSC data to one of the available models, using non-isothermal measurements at different heating rates.
dear merck i want learn Tg. recrystallizaton, and thermodynamic parameters
Actually first time i work on the dsc so i do not know much about it i want specially recrystallization peak you hve any dsc graph with interpretation plese send me
Glass transition temperature is the most important characteristic you can infer from a DSC spectra/graph. Now depending upon how advanced your DSC system is, there are many more thermal characteristic of materials you can infer. As per my knowledge one can expect the endothermic/exothermic phase transformation & phase change temperature data from any moder1n day DSC.
Hi Ravi, you can run DSC at lower scanning rate, say 2 C/min from room temperature to 250C and cool using identical rate on both samples and compare the thermograms. Normalize the curves before comparing their characteristic peak temperatures in the two distinct curves. Through this you can establish the effects of the ciprofloxacin hcl in your host polymer. Thus, it can either increase or decrease the Tg, melting or recrystallization temperatures if its a thermoplastic polymer.
Please see this reference:
www.perkinelmer.com/.../44-74542GDE_DSCBeginnersGuide.pdf
I used DSC to detect the glass transition temperatures of polymeric samples as well as the melting points of the ordered domains in semi-crystalline polymers. Thermal transitions change when there are impurities , when a polymer is converted into another polymer, and when a pure polymer is mixed with a pure simpler organic compound.
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