Macromolecular structure and liquid crystallinity

Abstract

The relationship between low-molar-mass or monomeric liquid crystals and polymeric liquid crystals is explored by examining the historical development of experimental and theoretical aspects of the latter materials. Polymeric liquid crystals are initially contrasted with conventional, non-mesogenic, flexible polymer chains (random coils), and then semiflexible and rigid-rod polymers are examined. Both thermotropic and lyotropic phases are described, with emphasis placed on the former; in particular, the relationship between dimers and polymers belonging to the semi-flexible category: [graphic omitted](mesogenic core)—(flexible spacer)[graphic omitted]_n. The review concludes by drawing attention to the curious behaviour of polypeptide liquid crystals (cholesteric compensation). The underlying theme of the lecture is the need to recognize the synergism and affinity that characterizes research on monomeric and polymeric liquid crystals.