Liquid crystalline properties and phase situations in 4-chlorobenzylidene-4 '-alkylanilines

On the basis of DSC calorimetry and thermo-optic (TOA) measurements the mes omorphic properties of the strongly polar Schiff bases family, 4-chlorobenz ylidene-4'-alkylanilines (CBnA), are presented. Two kinds of mesophases wer e found: smectic A and smectic B. For the first time detailed calorimetric properties of the investigated family are presented and discussed. Very nar row smectic A phase for the nonyl, decyl, undecyl and dodecyl derivatives w as detected. Smectic mesophases in butyl, pentyl and dodecyl derivatives ar e monotropic. These results are compared with our earlier results [1]. (C) 1999 Elsevier Science B.V. All rights reserved.