DILATOMETRIC BEHAVIOR OF POLYMORPHIC FORMS OF CHLORAMPHENICOL PALMITATE

The dilatometric behavior of two polymorphs of chloramphenicol palmitate was studied. The aspects investigated were (a) the melting behavior of Polymorphs A and B, and the delineation of their dilatometric profiles; and (b) the kinetics of phase transformation of Polymorph B to Polymorph A. The study emphasizes the complexity of the composition of Polymorph B of chloramphenicol palmitate. The studies dealing with the kinetics of phase transformation showed that the addition of increments of chloramphenicol stearate to a 99.9% chemically pure sample of Polymorph B of chloramphenicol palmitate slowed the rate of reversion to Polymorph A at 80°. Chloramphenicol heptadecanoate and nonadecanoate, stearic and palmitic acid, had no effect on the rate of transformation. Copyright © 1969 Wiley‐Liss, Inc., A Wiley Company