Abstract
A little previous work has been published on X-ray diffraction of acid potassium soaps. Piper reported a paper which gives only the long 'spacings for a series of acid potassium soaps and recently, Dumbleton reported the lattice constant of acid potassium myristate.
In this paper, X-ray investigation on acid potassium caprate, laurate, palmitate, stearate are reported. Acid potassium caprate and laurate were grown from ethanol solution in elongated parallelepiped form (Fig.-1·1), and acid potassium palmitate and stearate were in plates (Fig.-1·3). Acid potassium myristate is crystallized from hot alcohol in the elongated parallelepiped form (Fig. -1·2), but by slow precipitation it gives plate form (Fig.-1-3). The X-ray diffraction patterns showed remarkable difference between the elongated parallelepiped forms and the plates (Fig.-3·1). The cell dimensions for parallelepiped form were determined (Table-1).
It was concluded that there were two phases in acid soaps, one was elongated parallelepiped form (pseud-orthorhombic), and another was plate form (triclinic). It seemed that the stable phase for laurate and caprate was the former, while that for myristate, palmitate and stearate was the latter.
