Ring Opening Polymerization

Abstract

Biodegradable and biocompatible aliphatic polyesters have a great potential as biomaterials and environmentally friendly thermoplastics. An intensive research effort has been devoted to living or at least controlled ring opening polymerization (ROP) of lactones, lactides, and glycolides that contributes enormously to macromolecular engineering of these aliphatic polyesters. The recent progress in the field has been reviewed and discussed in terms of structure/nature of the polymerization promoters. A first section focuses on organometallic initiators and catalysts, with emphasis on the more efficient aluminum, tin, and yttrium alkoxides. Special attention is also paid to the steroselective ROP of D , L ‐ and meso ‐lactide into polylactide of controlled tacticity. Contamination of the final polyesters by metallic residues is a drawback, which is now tackled by grafting metal alkoxides onto solid supports. The second section is dedicated to ROP mediated by enzymes, which is a very attractive strategy. Finally, “all organic” processes have been recently worked out, which are very promising for the synthesis of aliphatic polyesters free from any metallic contaminants.

Ring-opening polymerization by lithium catalysts: an overview

“…ROP has been reviewed in the past in a few articles and book chapters. [8][9][10][11] The present review differs in content and in style from our previous review 11 and also from all other previous reviews on ROP. Moreover, the present review is devoted exclusively to ROP by lithium catalysts/initiators.…”

Synthesis of new substituted lactones by "click" chemistry

“…1 H NMR showed that the multiplet at 4.65 ppm assigned to the CH-Br proton disappeared and that a new multiplet was observed at 3.85 ppm characteristic of the CH-N 3 . 5-azidooxepan-2-one 10 and prop-2-yn-1-yl benzoate 11 were reacted at 35°C in the presence of CuI and Et 3 N. After 2 h, the IR absorption at 2100 cm The lactone 10 is a key derivative for the synthesis of a wide range of new functional lactones because of the variety of the structure of the alkyne that can be involved in the "click" reaction.…”

“…1 H NMR spectra were recorded at 400 MHz in the FT mode with a Brucker AN 400 apparatus at 25°C. FT-IR spectra were recorded with a Perkin Elmer One apparatus.…”

“…1 Among them, poly(oxepan-2-one), or poly(ε-caprolactone) (PCL), is commercialized by Solvay, Union Carbide and Daicel. 2 Nevertheless, the lack of pendant functional groups along the chains is a severe limitation for many applications.…”

Microwave-assisted in situ ring-opening polymerization of ε-caprolactone in the presence of modified halloysite nanotubes loaded with stannous chloride

“…5 Among them, the coordination-insertion polymerization is well studied because it can produce PCL with a clear structure and controllable molecular weights. 6 On the other hand, there are a wide variety of systems used to catalyse the ROP of 3-CL. Currently, the most commonly used catalyst systems mainly contain four types, i.e., metal-based compounds, enzymatic compounds, organic compounds and inorganic acids.…”