Ring-opening multibranching polymerization

Sunder, A., Hanselmann, R., Frey, H., and Mulhaupt, R. 1999. Controlled synthesis of hyperbranched polyglycerols by ring-opening multibranching polymerization. Macromolecules, 32, 4240 1246. 

Sunder A, Hanselmann R, Frey H, Mulhaupt R (2006) Controlled synthesis of hyper-branched polyglycerols by ring-opening multibranching polymerization. Macromolecules 32(13) 4240-4246... 

Sunder, Hanselmann, H., Frey H., and Miilhaupt, R., Controlled Synthesis of Hyperbranched Polyglycerols by Ring-Opening Multibranching Polymerization, Macromolecules, 32, 4240,1999. 

Fig. 33 Flow microreactor for synthesis of hyperbranched polyglycerol by ring-opening multibranching polymerization of glycidol. M micromixer...

Scheme 24.3 Anionic ring-opening multibranching polymerization of glycidol with 1,1,1-tris(hydroxymethyl)propane (trimethylol propane) as B3 initiator/core [16].

Figure 7.8 Synthesis of hyperbranched polytetritol (PolylOa and PolylOb) by ring-opening multibranching polymerization of 2,3-anhydroerythritol (10a) and 2,3-anhydro-DL-threitol (10b), respectively.

Imai, T., Satoh, T., Kaga, H. et al. (2004) Synthesis of hyperbranched carbohydrate polymer by ring-opening multibranching polymerization of 1,4-anhydroerythritol and 1,4-anhydro-L-threitol. Macromolecules, 37,3113-3119. 

Imai, T., Nawa, Y., Kitajyo, Y. et al. (2005) Synthesis of hyperbranched polytetritol by ring-opening multibranching polymerizations of 2,3-anhydroerythritol and 2,3-anhydro-Dl-threitol. Macromolecules, 38,1648-1654. 

Scheme 2 General principle of ring-opening multibranching polymerizations (ROMBPs). F is the single focal unit, while B depicts the reactive groups of the cyclic inimer.

Scheme 8 Synthesis of hyperbranched polyethers via cationic ring-opening multibranching polymerization of EHO.

Suzuki et al. [14] reported the Pd-catalyzed ring-opening polymerization of a cyclic carbamate in the presence of an initiator, which also acts as a core molecule, to afford a hyperbranched polyamine. The polymerization was proposed to be an in situ multibranching process, wherein the number of propagating chain ends increase with the progress of the polymerization. 

In 1992, Suzuki et al. reported palladium catalyzed, ring-opening polymerization (ROP) of a cyclic carbamate. The polymerization was proposed to be an in situ multibranching process. 

Figure 4 Synthesis of hyperbranched polyglycidol by anionic multibranching ring-opening polymerization. Reprinted from Wilms, D. Stiriba, S.-E. Frey, H. Acc. Chem. Res. 2010, 43,129. with permission of the American Chemical Society, USA.

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