Forming supramolecular networks from nanoscale rods in binary, phase-separating mixtures

Simulations show that when low-volume fractions of nanoscale rods are immer sed in a binary, phase-separating blend, the rods self-assemble into needle -like, percolating networks. The interconnected network arises through the dynamic interplay of phase-separation between the fluids, through preferent ial adsorption of the minority component onto the mobile rods, and through rod-rod repulsion. Such cooperative effects provide a means of manipulating the motion of nanoscopic objects and directing their association into supr amolecular structures. Increasing the rod concentration beyond the effectiv e percolation threshold drives the system to self-assemble into a Lamellar morphology, with layers of wetted rods alternating with layers of the major ity-component fluid. This approach can potentially yield organic/inorganic composites that are ordered on nanometer scales and exhibit electrical or s tructural integrity.