Study of binary systems inducing mesophase and determination of latent transition temperature

Five binary systems consisting of common component as nematogen (A), viz. p-(pʹ-n-propyloxybenzoyloxy)anisole is mixed with uncommon component (B) (nonmesogen or monotropic nematic), para-substituted Schiff bases, viz. X-C6H4-CH=N-C6H4-Y, where X = CH3, Cl, OCH3 and Y = OCH3 or OC2H5. Interesting results are obtained as (i) nematic mesophase maintained monotropically and enantiotropically from the binary systems with nonmesogen (B), (ii) smectic mesophase induced and nematic mesophase maintained from binary system comprising monotropic nematic component (B). Polarity and polarizability of terminal groups of component (B) play an important role in enhancing the liquid crystallinity. The group efficiency order is derived as, OC2H5 > CH3 = Cl. Latent transition temperatures of components (B) for smectic and nematic mesophascs are determined.