PREPARATION AND MESOMORPHIC PROPERTIES OF A HOMOLOGOUS SERIES OF -(2-CHLOROTEREPHTHALYLIDENE)BIS(4-N-ALKYLANILINE)S

A series of -(2-chloroterephthalylidene)bis(4-n-alkylaniline)s (CTBAAs ) were prepared and their mesomorphic behaviour characterized. None of the homologues showed smectic behaviour, but nematic behaviour with b road mesophases and rather low melting points was seen. The mesomorphi c behaviour was compared with that of N,N'-(terephthalylidene)bis(4-n- alkylaniline)s (TBAAs) and bis-(n-alkylbenzal)-2-chloro-1,4-phenylened iamines (BACPDs). An X-ray diffraction analysis of N,N'-(2-chloro-tere phthal)bis(4-n-butylaniline) (CTBBA) showed that the molecules were pa cked in crystals forming a staggered arrangement called an 'imbricated structure'.