Helical polymer-metal complexes HPMCs

Abstract New helical poly(phenylacetylene)s have been successfully designed and synthesised and their properties checked. The new polymers behave as sensors of metal cation valences and/or the polar and draior character of solvents. In the presence of metal salts, poly(phenylacetylene)s form helical polymer-metal complexes (HPMCs) that, in the case of a-methoxyphenylacetic acid (MPA)-containing poly(phenylacetylene), has led to a new family of nanospheres made by complex-ation between the polymer and divalent metal ions. These HPMC nanostructures present properties such as (1) their diameter can be tuned to different sizes, (2) the helicity of the polymeric material can be tuned to either of the two helical senses, and (3) they can encapsulate a number of inorganic and organic substances. These polymers also display phenomena such as helical inversion, chiral amplification and axial chirality selection, making them versatile materials. 

Methods based on the formation of complexes of CDAs with metal cations seem especially interesting for testing using PPAs, due both to the possibility of controlling the conformational equilibria at the pendants that will transmit further effects to the backbone, and to the potential role that metal ions could play in the establishment of supramolecular networks between the polymer chains (interchain bonding), giving birth to new types of nanostructures (i.e. helical polymer-metal complexes, HPMCs). 

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