THERMAL STUDY OF THE POLYETHYLENEGLYCOL 6000-TRIAMTERENE SYSTEM

This paper examines binary polyethyleneglycol (molecular weight 6000)-Triamterene (PEG 6000-T) solid dispersions (5-40 w/w% of T) prepared by the fusion carrirer method, and physical mixtures (5-90 w/w% of T) are studied using DSC and Hot Stage Microscopy (HSM). The use of these combined techniques allows to explain the thermal behaviour on the basis of dissolution of T in the liquid carrier according to the progressive disappearance of the original crystals over a wide range of temperatures (ca. 100-degrees-C). The above fact, and possibly the sublimation of T, also could explain that at low T content (less-than-or-equal-to 30 w/w%), DSC curves exhibited only a single endothermic peak and/or weak endothermic peaks. On the basis of DSC data, a tentative phase diagram of this system is proposed.