Abstract:

Proton magnetic resonance measurements were performed on $\alpha$- and $\beta$-polymorphs of tristearin (I) crystals. The spin-lattice relaxation time (T1) was measured at 20 MHz and 37° on the pure I crystals and on I crystd. in the presence of different solid surfactants. A significant neg. correlation for T1 values and different compns. of $\alpha$- and $\beta$-polymorphs in a mech. mixt. was found. The shortening of T1 relaxation time of the $\beta$-form was different for the various types of the added surfactants while they had no effect on the relaxation time of the $\alpha$-form. A model was proposed according to which the presence of additives, such as surfactants, generated vacancies within the crystal lattice of I and enhanced the freedom of rotation of the fat mol. about the terminal carbon-carbon bond. [on SciFinder(R)]