Stimuli-responsive supramolecular materials: photo-tunable properties and molecular recognition behavior

Abstract

A new homopolymer of polystyrene (PS) presenting pendant diaminopyridine (DAP) moieties has been prepared using controlled free radical polymerization and a CuAAC "click" reaction. Through directional complementary multiple hydrogen bonding, this PVB-DAP polymer underwent complexation with a thymine-functionalized azobenzene (Azo-T). The resulting supramolecular complex exhibited amorphous and chromophoric behavior without microphase separation. This strategy allowed the fabrication of homogeneous stimuli-responsive thin films with photocontrollable behavior through photoinduced trans-cis isomerization. The PVB-DAP/Azo-T supramolecular complex facilitated the dispersion of an azo-dye through noncovalent interactions; the resulting complex was used to fabricate a surface relief grating displaying an interference pattern. The "recordability" and "rewritability" of these supramolecular complexes suggest that they are promising materials for optical applications and therefore advance the pathway for supramolecular development.