| Abstract
| - Association of a 16-fold excess of a monodisperse telechelic oligo(THF) (Mw = 1270 g/mol)containing two end groups that selectively bind to the 32 binding sites of a fifth generation dendritic host(Mw = 18 511 g/mol and radius Rh = 2.4 nm) results in the formation of reversible and dynamicsupramolecular complexes. The structure of these complexes in solution depends strongly on theconcentration. At low concentration, the two end groups of one guest are proposed to complex to thesame host, and flowerlike structures are formed with a radius of Rh = 3.7 nm. At higher concentrations,both end groups of one guest are complexed to different hosts, forming a bridge between them. This givesrise to the formation of larger associates, and eventually to a transient supramolecular network. Dynamiclight scattering unequivocally showed that three distinct relaxation processes, associated with the proposedstructures, are present in this system. In addition to the dynamics related to the flowerlike (fast) and thetransient network structures (slow), an intermediate dynamic process is attributed to the cooperative motionof a few (∼6) connected flowerlike structures. Rheological data elucidate the nature of the intermittentnetwork responsible for the slowest process. A monofunctional guest, not capable of forming a networkstructure, was used as a reference, and starlike supramolecular structures are formed at all concentrations,indeed.
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