Arm-First Divergent Iterative Methodology

As mentioned above, some difficulties arose in the synthesis of dendrimer-like star-branched polymers by the two aforementioned methodologies based on the core-first divergent and arm-first convergent approaches described in Sections 5.2.1 and 5.2.2. In fact, most of the polymers are limited to 4G stages and a few 10 g/mol orders in molecular weight except for two cases reported by Gnanou et al. (Tables 5.1 and 5.2). Moreover, the structures of the resulting polymers could not be well characterized and structural imperfections were indicated in several cases. 

The versatility of the present iterative methodology based on the arm-first divergent approach can be witnessed by the number of structural variations in the resulting polymers. For instance, a series of highly branched dendrimer-like star-branched (PMMA)s could be 

124 PS segments (Mn = about 15000g/mol) with 128 BnBr termini (Table 5.4). Two 3G 

---

Table 5.3 Synthesis of dendrimer-like star-hranched (PMMA)s hy the arm-first divergent iterative methodology...

---