Solvent-Free Glycidyl Carbamate Oligomerization and Solvent Affinity of Oligomers

Abstract

Polyglycerols are a class of multifunctional polymers obtained from the polymerization of glycidol and its derivatives. Unlike poly(ethylene glycol) (PEG), which is the most common polyether, polyglycerols can exhibit many functionalities on their side chains and can be obtained from renewable resources, mainly glycerol. Hereby, this study will focus on glycidyl carbamates, a new class of monomers readily available from glycerol carbonate, which combines the chemical functionalities of both glycidol and urethane. The polymerization of these glycidyl ethers directly leads to linear poly(glycidyl carbamates), thus avoiding several protection and deprotection steps of the monomers or polymers. This study hence gives a first approach to glycidyl carbamate polymerization. Commonly used initiators in anionic ring-opening polymerization (alkali metal alkoxides) lead to ill-defined compounds after full conversion of the monomers, whereas pyridine derivative initiators lead to oligomers whose structures could be thoroughly described. The results suggest that low basicity and high nucleophilicity are the most suitable conditions to polymerize glycidyl carbamates because of the sensitivity of the urethane moiety. Additionally, a study of the obtained poly(glycidyl carbamates) affinity toward the solvent has been conducted to further describe the properties of these novel original polyethers.