Interplay of Chiral Side Chains and Helical Main Chains in Polyisocyanates
Here we describe the synthesis of seven new copolymer series prepared by copolymerization of hexyl isocyanate with seven new chiral azo chromophores with an isocyano functionality. The resulting copolyisocyanates (Nylon 1) possess a helical polymer conformation. In the cases in which the chiral group and polymer chain are linked to the same phenyl ring (copolymer series VI-IX) a transfer of chirality to the polymer chain is possible. I.e. one helical twist sense is preferred in this case. By variation of the chiral center, polymers with preferable right- or left-handed helical conformation are accessible. The photochemical isomerization of the azo chromophore (trans → cis) is possible in hi…