Many pharmaceutical solids exhibit polymorphism, i.e., the ability of a substance to exist in different crystalline forms. The polymorphic form can have significant influence on pharmaceutical processing and can, for example, affect grinding, granulation and tabletability. A DSC measurement allows for the characterization of the present modification. Here, different modifications of paracetamol are distinguished by means of DSC.
E. Post, J. Blumm
A phase diagram portrays the equilibrium conditions between the thermodynamically separated phases or it shows which phases are present in the material system at different temperatures, pressures and compositions. Thermoanalytical methods play an important role in establishing binary and ternary phase diagrams. They are based on the principle that, when a phase transition occurs, the physical, chemical and/or structural properties change.