Dendrimer-like polymers

From Star-Like to Dendrimer-Like Polymers... 

Dendrimer-like polymers are dendrimers that not only feature tmly macromolecular generations, but can also be viewed as an extension of star polymers with the presence of a central core (Figure 27.1) (7, 10, 11]. Like dendrimers, these polymers possess a precise number of branching points that are distributed regularly throughout the dendritic structure (in contrast, for instance, to dendtigrafts), as well as a more dense surface functionahty than do stars, due to their numerous terminal functions. Although more... 

Figure 27.1 Various branched polymers with their compared size, including star-like and dendrimer-like polymers. CLP, controlled/living polymerization.

In this chapter, details are presented of the synthetic access to star-like and dendrimer-like polymers, and of their relevant structural characteristics. Due to limited space, an exhaustive review of the state of the art of the subject is impossible here rather, the aim is simply to highlight the merits, drawbacks, and possibilities for each synthetic approach. 

The first example of a dendrimer-like polymer (in fact, a dendrimer-like PEO of the third generation) was described in 1995 by Gnanou et al. [10]. Iterative synthetic approaches, using either a divergent or a convergent strategy, can be followed... 

General Methods jbr the Synthesis of Dendrimer-Like Polymers I 833... 

It has been proved that, as analogues of hyperbranched polymers, dendrimer-like polymers are not a self-similar objective, i.e., the classic scaling laws between their sizes (/ ), intrinsic viscosities ([) ]) and molar masses (Af) are not valid for dendrimer-like polymers, which is partially because the hydrodynamic radius (l h) is not proportional to the radius of gyration (i g) [59-61]. There exists a maximum in the plot of [r] versus M, i.e., [jj] first increases with the number of generation (G) and then decreases after G reaches a certain value, as shown in Fig. 1.4 [59]. 

Matmour, R. and Gnanou, Y. (2008) Combination of an anionic terminator multifunctional initiator and divergent carbanionic polymerization application to the synthesis of dendrimer-like polymers and of asynunetric and miktoarm stars. Journal of the American Chemical Society, 130,1350-1361. 

Taton, D., Gnanou, Y., Matmour, R. et al. (2006) Controlled polymerizations as tools for the design of star-like and dendrimer-like polymers. Polymer International, 55,1138-1145. 

Taton, D., Feng, X., and Gnanou, Y. (2007) Dendrimer-like polymers a new class of structurally precise dendrimers with macromolecular generations. New Journal of Chemistry, 31,1097-1110. 

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