Ring-opening polymerization of cyclic ethers initiated by benzazaphosphole-W(CO)5/silver hexafluoroantimonate

Abstract Ring-opening polymerization is defined by IUPAC (Penczek, S., Moad, G. (2008). Glossary of the terms related to kinetics, thermodynamics, and mechanisms of polymerization. (IUPAC Recommendations 2008), Pure and Applied Chemistry, 80(10), 2163–2193) as (cit.) “Ring-opening polymerization (ROP): Polymerization in which a cyclic monomer yields a monomeric unit that is either acyclic or contains fewer rings than the cyclic monomer”. The large part of the resulting polymerizations is living/controlled; practically all belong to chain polymerizations. After the introduction, providing basic information on chain polymerizations, the paper presents the concise overview of major classes of monomers used in ROP, including cyclic ethers, esters, carbonates, and siloxanes as well as cyclic nitrogen, phosphorus, and sulfur containing monomers. There are discussed also thermodynamics, kinetic polymerizability, and major mechanisms of ROP. Special attention is concentrated on polymers prepared by ROP on industrial scale.

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Cationic indium complexes for the copolymerization of functionalized epoxides with cyclic ethers and lactide

Chemical Communications ◽

10.1039/c8cc08858f ◽

2019 ◽

Vol 55 (23) ◽

pp. 3347-3350 ◽

Cited By ~ 6

Author(s):

Carlos Diaz ◽

Tannaz Ebrahimi ◽

Parisa Mehrkhodavandi

Keyword(s):

Molecular Weight ◽

High Molecular Weight ◽

Ring Opening ◽

Ring Opening Polymerization ◽

Cyclic Ethers ◽

Indium Complexes ◽

Salen Complexes ◽

Kinetic Investigations

Cationic indium salen complexes are active catalysts for the ring opening polymerization of epoxides and other less strained cyclic ethers. Moreover, they are competent catalysts in the copolymerization of rac-lactide and epoxides to high molecular weight copolymers. Preliminary kinetic investigations with different cationic complexes revealed subtle effects of their solvent donors in the initiation rates of polymerization of epoxides.

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Structures and potential applications of multihydroxyl branched polyethers obtained by cationic ring-opening polymerization involving activated monomer mechanism

e-Polymers ◽

10.1515/epoly.2008.8.1.809 ◽

2008 ◽

Vol 8 (1) ◽

Cited By ~ 1

Author(s):

Melania Bednarek

Keyword(s):

Ring Opening ◽

Star Polymers ◽

Ring Opening Polymerization ◽

Cyclic Ethers ◽

Low Molecular Weight ◽

Hydroxyl Groups ◽

Potential Applications ◽

Cationic Ring Opening Polymerization ◽

Highly Strained ◽

Thermodynamic Restrictions

AbstractThe synthesis and potential applications of functional, branched polyethers prepared by cationic ring-opening polymerization is reviewed, mainly on the base of the work from the author’s laboratory. Polymerization of cyclic monomers of ABx type, including highly strained 3- and 4-membered as well as weakly strained 5-membered cyclic ethers substituted with hydroxyl groups is discussed. Cationic polymerization of such monomers proceeds with participation of activated monomer mechanism which leads to the formation of branches. Hydroxy-substituted 4-membered cyclic ethers are highly strained; thus there are no thermodynamic restrictions for their polymerization, but these monomers are not easily available. Thus the possibility of using easily accessible 5-membered hydroxy-substituted cyclic ethers as monomers for cationic ring-opening polymerization was explored in spite of expected thermodynamic limitations due to low ring strain of those monomers. It was found that 5-membered hydroxysubstituted cyclic ethers undergo polymerization; however only low molecular weight products may be obtained from these monomers. It is shown in this review that such products may be useful and some examples of their applications in further synthesis e.g. in the preparation of star polymers and as surface modifying agents in the synthesis of organic/inorganic hybrid materials are described.

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