Small‐Molecule‐Induced Folding of a Synthetic Polymer

Stack 'em high: A polyimide with pyromellitic diimide units linked by hexaoxyethylene segments can be made to fold by cooperative two-point interactions on addition of a folding agent (see scheme). The ammonium group of the folding agent forms complexes with the oxyethylene spacer which greatly facilitates the formation of charge-transfer complexes between the aromatic units of the two components.