Ring-opening polymerization epoxide

Boileau, S., Anionic Ring-Opening Polymerizations Epoxides and Episulfides, pp. 467 487 in Comprehensive Polymer Science, Vol. 3, G. C. Eastmond, A. Ledwith, S. Russo, and P. Sigwalt, eds., Pergamon Press, London, 1989. 

BoUeau S. Anionic ring-opening polymerizations epoxides and episulfldes. In Eastmond GC, Ledwith A, Russo S, Sigwalt P, editors. Comprehensive Polymer Science. Chain polymerization. Volume 3. Oxford Pergamon 1989, Part I. p 467. 

An alternate way to make block copolymers involving PDMS blocks 124,125) is to have these chains fitted with epoxide functions at chain end, and to react them with a vinylic or dienic polymer carrying terminal COOH functions. Sequential addition of monomers has also been used, the ring opening polymerization of the cyclic trimer (D3) being initiated by the anionic site of a living polymer126). 

The simplest model compound is cyclohexene oxide III. Monomers IV, V and VII represent different aspects of the ester portion of I, while monomers VII and VIII reflect aspects of both the monomer I and the polymer which is formed by cationic ring-opening polymerization. Monomers IV-VII were prepared using a phase transfer catalyzed epoxidation based on the method of Venturello and D Aloisio (6) and employed previously in this laboratory (7). This method was not effective for the preparation of monomer VIII. In this specific case (equation 4), epoxidation using Oxone (potassium monoperoxysulfate) was employed. 

Curing of epoxy resins can also be achieved by ring-opening polymerization of epoxide groups using either Lewis acids (including those generated photochemically) or Lewis bases (Sec. 7-2). 

Dreyfuss, P. and M. P. Dreyfuss, 1,3-Epoxides and Higher Epoxides, Chap. 2 in Ring-Opening Polymerization, K. C. Frisch and S. L. Reegan, eds., Marcel Dekker, New York, 1969. 

The stereochemistry of ring-opening polymerizations has been studied for epoxides, episul-fides, lactones, cycloalkenes (Sec. 8-6a), and other cyclic monomers [Pasquon et al., 1989 Tsuruta and Kawakami, 1989]. Epoxides have been studied more than any other type of monomer. A chiral cyclic monomer such as propylene oxide is capable of yielding stereoregular polymers. Polymerization of either of the two pure enantiomers yields the isotactic polymer when the reaction proceeds in a regioselective manner with bond cleavage at bond 1. 

The stereochemistry of ring-opening polymerizations of episulfides, lactones, lactides, IV-carboxy-a-amino acid anhydrides, and other monomers has been studied but not as extensively as the epoxides [Boucard et al., 2001 Chatani et al., 1979 Duda and Penczek, 2001 Elias et al., 1975 Guerin et al., 1980 Hall and Padias, 2003 Imanishi and Hashimoto, 1979 Inoue, 1976 Ovitt and Coates, 2000 Spassky et al., 1978 Zhang et al., 1990]. 

The ring-opening polymerization of cyclic ethers having 3-, 4-, and 5-membered rings (e.g., epoxides, oxetanes, THF) yields polymeric ethers. Six-membered rings (1,4-dioxane) are not capable of polymerization. 

Polymerization using epoxides as monomers includes the ring opening of epoxides via C-O bond cleavage. Thus, a mode of G-O bond cleavage (Sn2 or SnI) and selectivity, that is, which C-O bond is cleaved, coupled with the symmetry of epoxides (symmetrical or unsymmetrical), cause regio- and stereochemical issues to be controlled in the epoxide polymerization. 

For the (coordination) anionic polymerization, metal alkoxides are often employed as initiators. In this system, the ring opening of epoxide takes place by a nucleophilic attack of an alkoxide on the (activated) epoxide carbon to generate another metal alkoxide which behaves as the propagating species (Scheme 3), The nature of metal-alkoxide... 

Ring-Opening Polymerization of Epoxide Initiated with... 

Living and Immortal Ring-Opening Polymerizations of Epoxide... 

Ring-Opening Polymerization of Epoxide Initiated with Aluminum Porphyrin in the Presence of an Organoaluminum Compound [60]... 

Ring-Opening Polymerization of Epoxide with Various Aluminum Complexes as Initiators in the Presence of a Lewis Acid... 

Ishii.Y., Sakai, S. 1,2-epoxides. In Frisch,K. C., Reegen,S.L. (Eds.) Ring opening polymerization. New York-London Marcel Dekker 1969. 

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