Self polymeric superstructures

These examples serve to highlight that supramolecular self-assembly and topo-chemical diacetylene polymerizations are a perfect match. Topochemical diacetylene polymerizations are an advantageous means of covalent capture for the reasons outlined above. The required order may, on the other hand, be provided by supramolecular self-assembly, which extends the scope beyond singlecrystalline monomers. This aspect becomes particularly important in the case of functional monomers in order to address specific applications. However, in contrast to previous investigations, the targeted preparation of hierarchically structured poly (diace tylene)s with a defined, finite number of strands required the presence of equally well-defined, uniform supramolecular polymers [106] with the propensity to form predictable superstructures, instead of micellar or vesicular ID aggregates. 

In contrast, recent kinetic investigation of the polymerization of spacerless G2 dendron-substi-tuted styrene and methylmethacrylate, respectively, in solution lead to the unexpected conclusion that above a certain critical monomer concentration a strong increase in the rate of the free radical polymerization is observed [21]. The results can be explained by self-organization of the growing polymer chain to a spherical or columnar superstructure in solution, depending on the degree of polymerization (DP, Fig. 2). The rate constants and low initiator efficiency lead one to conclude that the self-assembled... 

Larger superstructures can be formed by the subsequent aggregation of discrete assemblies or directly from self-assembling subunits that are designed to form polymeric aggregates. Along these lines, Kimizuka and Kunitake have... 

Another template-free method for the formation of self-assembled tubular structures has been shown by Jiang and co-workers. They used polymeric Janus particles prepared from mixed-shell micelles (MSMs) that self-assembled into tubular superstructures and nanosheets. The micelles were prepared by non-covalent cross-linking of poly(acrylic acid) (PAA) blocks by addition of 1,2-propanediamine (PDA) in DMF (A on Figure 5.45). The two block copolymers were composed of hydrophilic poly(ethylene... 

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