Hyperbranched polymers condensation strategies

CONDENSATION STRATEGIES TO HYPERBRANCHED POLYMERS - COMMERCIAL PRODUCTS... 

Although the first examples of hyperbranched polymers proposed by Flory involved condensation-type polymerization strategies, the first well-characterized hyperbranched example involved the ring-opening polymerization of 2-carboxylic-2-oxazoline derivatives. As early as 1988, Odian and Tomalia [2] reported the ring-opening polymerization of these derivatives to form random... 

The first strategies to random hyperbranched polymers involved exclusively step-growth polymerizations. This limited the potential applications for these architectures to areas where only condensation-type polymers are acceptable. Frechet et al. [21] presented the first example of a hyperbranched vinyl polymerization in 1995, ] initiating the birth of a second generation of hyperbranched... 

Scheme 30.20 Preparation of a heterofunctional hyperbranched polymer via the self-condensing ATRP of an azide-functional inimer and subsequent click coupling combined with the grafting-from strategy to afford multihetero-arm hyperbranched brushes. Reproduced with permission from Ref [149] 2009, The Royal Society of Chemistry.

Different synthetic strategies have been employed for the preparation of the pure organic hyperbranched polymers [23-25]. The most commonly adopted approach is self-condensation of AB -type monomers with n > 2 [26-29]. This type of polymerization can be carried out in a concurrent mode or by slow addition of the monomer or even in the presence of a core molecule of By (/ > 3), which allows various structural control over the growing polymer [30-32]. Another approach is copolymerizations of A monomers with B comonomers (n > 3) [33-35]. However, the stoichiometric requirements between the pairs of the functional comonomers... 

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