Helix-sense-selective polymerization of achiral substituted acetylene in chiral micelles for preparing optically active polymer nanoparticles: Effects of chiral emulsifiers

This paper reports helix-sense-selective polymerizations (HSSPs) of achiral acetylene monomer performed in chiral micelles, by which optically active helical polymer emulsions were directly obtained. The chiral micelles were constructed by chiral emulsifiers, in which achiral acetylene underwent HSSPs in the presence of catalyst [(nbd)RhCl](2). The chiral emulsifiers possessed different alkyl chain lengths and different amino acid groups, and their effects on HSSPs were investigated in detail. The obtained polymer emulsions were characterized by TEM, circular dichroism and UV-vis absorption spectroscopy techniques. It is demonstrated that the polymer chains constructing the emulsions adopted helical structures of predominantly one-handed screw sense, from which the emulsions exhibited remarkable optical activity. (C) 2013 Elsevier Ltd. All rights reserved.