Dendritic polymer synthesis

J.M.J. Frechet (C. J. Hawker, 1990) replaced the divergent synthesis by a convergent growth of a dendritic polymer. The repeatedly employed monomer, 5-hydroxymethyl-l, 3-benzenediol, was 1,3-O-dibenzylatcd with 3,5-bis(benzyloxy)benzyl bromide. The resulting benzyl alcohol containing 7 benzene rings was converted to the benzyl bromide which was... 

The use of dendritic cores in star polymer synthesis by NMP, ATRP and RAFT polymerization was mentioned in Section 9.9.1, In this section wc describe the synthesis of multi-generation dendritic polymers by an iterative approach. 

The first steps of a second process for divergent synthesis of dendritic polymers by ATRP are shown in Scheme 9.73.12S In this case, a caiixarcnc core... 

Chapman et al. [131] reported the synthesis of poly(ethylene oxide) (PEO) supported dendritic f-BOC-poly(a, c-L-lysines). These dendritic polymers termed as hydramphiphiles formed foams possessing good temporal stability in aqueous solution. Scrimin et al. [132] synthesized a three-directional polypeptide having uses in membrane permeability modulation. Decapeptide fragments were linked to TREN [tris(2-aminoethyl)amine] core. 

Dendritic polymers, fullerene, 12 252 Dendritic salt, 22 805 Dendritic siloxanes, synthesis of, 22 554 Dendrobine, 2 102... 

Since the successful synthesis of dendritic macromolecules from low MW monomers [14a], research has also been performed in the area of dendritic polymers [14b, 15]. Dendritic polymers are obtained by attaching or growing several end-standing arms onto a central regular star polymer. This procedure is repeated in a generational manner, see Figure 3.3. 

The synthesis of well-defined LCB polymers have progressed considerably beyond the original star polymers prepared by anionic polymerization between 1970 and 1980. Characterization of these new polymers has often been limited to NMR and SEC analysis. The physical properties of these polymers in dilute solution and in the bulk merit attention, especially in the case of completely new architectures such as the dendritic polymers. Many other branched polymers have been prepared, e.g. rigid polymers like nylon [123], polyimide [124] poly(aspartite) [125] and branched poly(thiophene) [126], There seems to be ample room for further development via the use of dendrimers and hyperbran-... 

Since that time, synthetic chemists have explored numerous routes to these statistically hyperbranched macromolecular structures. They are recognized to constitute the least controlled subset of structures in the major class of dendritic polymer architecture. In theory, all polymer-forming reactions can be utilized for the synthesis of hyperbranched polymers however, in practice some reactions are more suitable than others. 

Another important issue is the difference between various branching types such as random hyperbranched [31], dendrigrafts and dendrimers. The complexity of synthesis requirements manifested by the statistical dendritic polymers versus the more structurally controlled dendrimers could make the former orders of magnitude more expensive than hyperbranched. Are the structures as significantly unique and of sufficient value effectiveness to justify the higher costs ... 

Tomalia, D. A. and Dvornic, P. R. Dendritic polymers, divergent synthesis (starburst polyamidoamine dendrimers) , in Salamone, J. C. (ed.), Polymeric Materials Encyclopedia, Vol. 3, CRC Press, Boca Raton, FL, 1996, pp. 1814-1830. 

Dendritic Polymers as High-Loading Supports for Organic Synthesis and Catalysis... 

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