We report here the self-assemblystudies of 22 polycarbodiimides(PCDs) in complex morphologies such as fibers, looped fibers, fibrousnetworks, ribbons, worm-like aggregates, toroidal structures, andcraters that were examined by combination of TMAFM, TEM, SEM, andpowder XRD methods as well as semiempirical modeling. Morphology characterizationin the thin film (TMAFM, TEM) and in bulk (SEM, pXRD) revealed theformation of fiber-like aggregates assembled from the bundles of individualhelices. In certain cases superhelical motifs of both right- and left-handedscrew senses were identified. It seemed likely that the great varietyof morphologies observed is a result of extensive hydrophobic sidechain/side chain interactions of the singular polycarbodiimide strands. [ABSTRACT FROM AUTHOR]