We found that the amplification of weak multiple interactions between numerous peripheral branches of irregular, flexible, polydisperse, and highly branched molecules can facilitate their self-assembly into nanofibrillar micellar structures at solid surfaces and the formation of perfect long microfibers in the course of crystallization from solution. The core-shell architecture of the amphiphilic dendritic molecules provides exceptional stability of one-dimensional nanofibrillar structures. The critical condition for the formation of the nanofibrillar structures is the presence of both alkyl tails in the outer shell and amine groups in the core/inner shell. The multiple intermolecular hydrogen bonding and polar interactions between flexible cores stabilize these nanofibers and make them robust albeit flexible. This example demonstrates that one-dimensional supramolecular assembling at different spatial scales (both nanofibers and microfibers) can be achieved without a tedious, multistep synthesis of shape-persistent molecules.

lished procedures [16]. To create PDMS replicas, 10:1 PDMS:crosslinking agent is poured onto the lTM, cured on silanized lTMs at 60 C for 3 h, and manually removed. To create polyurethane (PU) replicas, PU prepolymer (J-91, Summers Optical, Fort Washington, PA) was cured on silanized lTMs using a 10 min exposure to longwave UV light (UVP Blak-Ray Model B-100A, Upland, CA).Membrane Deflection Measurements: Replicas and molds were cross-sectioned with a razor blade and imaged with a handheld digital camera (resolution 2048 1536 pixels) and a stereomicroscope. Feature dimensions were converted to pixels using imaging software; the microns/pixel conversion factor was obtained by measuring features of known size (e.g., the width of the membrane) present in the same imaging plane. A variety of molecular designs have been proposed for the fabrication of one-dimensional (1D), self-assembled, noncovalently linked nanostructures. [1,2] The appropriate balance of hydrophobic and hydrophilic interactions, enhanced by hydrogen bonding, p±p stacking interactions, and steric factors is considered a powerful tool for inducing the formation of organized surface nanostructures from branched and dendritic polymeric and organic molecules. Received[1±8] The tightly controlled internal organization of these nanostructures makes them promising candidates for templated inorganic assemblies, or-COMMUNICATIONS

One‐dimensional supramolecular assembly of dendrimers (see picture) has been achieved by multiple weak interactions between highly branched molecules with irregular structures. This finding contradicts the widely accepted assumption that precise matching of directional interactions and steric constraints is required to facilitate long‐range one‐dimensional supramolecular assembly.

Nanofibrillar micellar structures formed by the amphiphilic hyperbranched molecules within a Langmuir monolayer were utilized as matter for silver nanoparticle formation from the ion-containing water subphase. We observed that silver nanoparticles were formed within the multifunctional amphiphilic hyperbranched molecules. The diameter of nanoparticles varied from 2-4 nm and was controlled by the core dimensions and the interfibrillar free surface area. Furthermore, upon addition of potassium nitrate to the subphase, the Langmuir monolayer templated the nanoparticles' formation along the nanofibrillar structures. The suggested mechanism of nanoparticle formation involves the oxidation of primary amino groups by silver catalysis facilitated by "caging" of silver ions within surface areas dominated by multibranched cores. This system provides an example of a one-step process in which hyperbranched molecules with outer alkyl tails and compressed amine-hydroxyl cores mediated the formation of stable nanoparticles placed along/among/beneath the nanofibrillar micelles.

Long-term stability and self-recovery properties were studied for the compliant nanomembranes with a thickness of 55nm free suspended over openings of several hundred microns across. These nanomembranes were assembled with spin-assisted layer-by-layer routines and were composed of polymer multilayers and gold nanoparticles. In a wide pressure range, the membranes behave like completely elastic freely suspended plates. Temporal stability was tested under extreme deformational conditions close to ultimate strain and very modest creep behavior was observed. A unique “self-recovery” ability of these nanomembranes was revealed in these tests. We observed a complete restoration of the initial nanomembrane shape and properties after significant inelastic deformation. These unique micromechanical properties are suggested to be the result of strong Coulombic interaction between the polyelectrolyte layers combined with a high level of biaxial orientation of polymer chains and in-plane prestretching stresses.