Abstract:

Sorbitan esters and other solid emulsifiers had no effect on the x-ray diffraction patterns of the stable $\beta$ polymorphs of trilaurin [538-24-9] and tristearin [555-43-1]. Plots of heat capacities (C+) of the polymorphs vs. temp. had divergence points with increase of slope at the onset of 2-dimensional melting. Sorbitan esters did not affect the Cp values of tristearin below the divergence point but increased the values for only the $\beta$-form above this point. Acridan [92-81-9] and Dimodan [31566-31-1] increased the Cp of tristearin in both forms through the whole range of temp., up to melting. Phase diagrams of tristearin with 2 sets of emulsifiers were constructed. All solid emulsifiers could be incorporated in tristearin forming one phase, but tristearin could be similarly incorporated only in sorbitan esters. Sorbitan esters increased the value of the heat of fusion of $\alpha$-trilaurin whereas other solid emulsifiers did not. Explanations were suggested by taking into account the degree of structural compatibility between the triglycerides and the solid emulsifiers. [on SciFinder(R)]