Study of the mesomorphic behaviour of ternary mixtures of alkoxybenzalazines by means of the Scheffé design

The Scheffe design was applied to a ternary mixture of 4,4′-diethoxy-2,2′-dihydroxy-α,α-dimethylbenzalazine, 4,4′-dipropoxy-2,2′-dihydroxy-α,α'-dimethylbenzalazine and 4,4′-dibutoxy-2,2′-dihydroxy-α,α-dimethylbenzalazine in order to improve the physical properties of each individual component. Twenty-two different mixtures were selected and their thermodynamical properties measured. A third order model was chosen to account for the experimental measurements. Thus, it was possible to determine the best region in the ternary diagram.