Branched polymers architecture

Iedema, P.D. and Hoefsloot, H.C.J. (2001) Synthesis of branched polymer architectures from molecular weight and branching distributions for radical polymerisation with long-chain branching, accounting for topology-controlled random scission. Macromol. Theor. Simul., 10, 855. 

Figure 2.2. Branched polymer architecture as demonstrated by Flory by the assembly of AB2-type monomers.

Complex Architectures. Perhaps the most significant recent advances in molecular understanding of polymer melts have emerged from the study of branched polymer architectures. We have noted above how a tube theory for star-polymers provided the means to treat fluctuations in entangled path length in linear polymers (see Figure lb). This is simply due to the complete suppression of reptation in star polymers without fluctuation there is no stress-relaxation at all ... 

Fig. 1). These include linear polyethylene and polypropylene imines of varying degree of polymerization (Pn = 10 to 20) in non-methylated (PEI and PPI) and methylated (PMEI and PMPI) forms, which were specifically synthesized. Hexaazadocosane, which may be regarded as a model for a PPI with Pn = 6, was prepared by Michael addition of acrylonitrile to spermidine [12]. In addition, a commercially available PEI with high molecular mass and with a branched polymer architecture was employed. 

B.I. Voit, A. Lederer, Hyperbranched and highly branched polymer architectures— synthetic strategies and major characterization aspects, Chem. Rev. 109 (11) (2009) 5924-5973. 

Voit B I, Lederer A (2009) Fiyperbranched and Fiighly Branched Polymer Architecture-Synthetic Strategies and Major Characterization Aspects. Chemical reviews 109 5924-5973. 

One of the recent advancements and interests in alkyd resin technology is hyperbranched alkyd resins, which, due to their unique highly branched polymer architecture, have low viscosities at higher MWs. An important characteristic of these alkyds is rapid drying. Generally they are prepared by reacting hyperbranched polyester polyols with fatty acids. The main limitation of such alkyds, however, is higher cost, due to the need for unique, more expensive raw materials in their synthesis. 

Voit Bl, Lederer A (2009) Hyperbranched and highly branched polymer architectures-synthetic strategies and majm characterization aspects. Chem Rev 109 5924—5973... 

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