This tutorial review presents current progress in the synthesis of helical polyacetylene (H-PA) using a chiral nematic liquid crystal reaction field as an asymmetric polymerisation solvent. In addition, we review the morphology-retaining carbonisation for helical graphite using H-PA as a carbonisation precursor. Carbonisation of H-PA films, via iodine doping, is demonstrated to produce carbon and graphitic films bearing completely preserved morphologies and even helical nanofibril structures.
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We report the helix-sense-selective memory polymerization (HSMP) of achiral biphenylylacetylenes bearing carboxy and amino pendant groups in the presence of basic and acidic chiral guests in water, respectively. The HSMP proceeds in a highly helix-sense-selective manner driven by noncovalent chiral ionic interactions between the monomers and guests under kinetic control, producing the one-handed helical polymers with a static memory of helicity in one-pot during the polymerization in a very short time, accompanied by amplification of asymmetry. The carboxy-bound helicity-memorized polymer self-assembles into a cholesteric liquid crystal in concentrated water, in which a variety of basic achiral fluorophores further co-assembles to form supramolecular helical aggregates that exhibit an induced circularly polarized luminescence in a color tunable manner.
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