Abstract:

Polymorphic transformations of stearic acid in their crystn. solns. were studied. When stearic acid crystals were left in the ethanolic satd. mother liquor, the B-form modification was obtained throughout the whole process. In hexane and benzene during the first 2-3 h, the C-polymorph was the predominant form and later transformed progressively into the B-form so that towards the end of the expt. the whole ppt. was in the B-form. The proposed explanation is that the transformation is due to dissoln. caused by thermal fluctuation in the bath, and subsequent pptn. The dissoln. and repptn. was followed up by micro photographs. In the presence of Span 60, only the C form was obtained in all solvents. [on SciFinder(R)]