Characterization and thermal stability of polymorphic forms of synthesized tristearin

The polymorphic characteristics and thermal stability of alpha, beta', and beta forms of synthesized tristearin were studied using X-ray diffractometry (XRD), differential scanning calorimetry (DSC), polarized light microscopy (PLM), and scanning electron microscopy (SEM). Polymorphic forms of alpha, beta'; and beta were induced from tristearin melts with increasing temperatures and times. Solid-solid and melt-mediated polymorphic transitions of tristearin occurred predominantly during slow heating rates and rapid heating rates in the DSC, respectively. The stability of alpha and beta' forms of tristearin were dependent on storage temperatures. As storage temperatures increased, the rate of polymorphic transitions from alpha to beta and beta' to beta forms of tristearin increased.