Helical polymerisation using a polymer network derived from a blue phase as a template for chirality transfer

We prepared a blue phase (BP) liquid crystal mixture consisting of a T-shaped nematic liquid crystal, a chiral dopant, a reacting monomer mixture and a photo-initiator. It exhibited a phase sequence of Iso-BPIII-cubic BP-N* on cooling. We produced the polymer stabilised cubic BP (PS-cubic BP) and BPIII (PS-BPIII). After washing low-molar-mass materials from each PS-BP, we obtained the corresponding polymer networks. Marked difference exhibited in a three-dimensional structure between the BPIII and cubic BP polymer networks. Although they were prepared by the photopolymerisation of achiral monomers, they showed optical activities. Furthermore, they proceed the helical polymerisation of achiral reactive monomers to produce a chiral polymer film. The optical handedness of the polymer film is corresponded to that of the original BP. We discuss how the chirality is transferred from each BP to the corresponding polymer film.